Sep 252017
 

The average North American child can identify over 300 corporate logos, but only 10 native plants or animals – a telling indictment of our modern disconnection from the natural world. Even though children are born with an innate interest in nature, our society does little to nurture this predisposition. It is largely for this reason that Jacob Rodenburg, Executive Director of Camp Kawartha, and I decided four years ago to sit down and write a book to help address this problem.
Released just last week by New Society Publishers, “The Big Book of Nature Activities: A year-round guide to outdoor learning” sets out to answer the question “What can you do outside in nature?” In response, the book provides nearly 150 activities, including games, crafts, drama, and stories. It will also help young and old alike to become more aware of how the sights, sounds, smells, textures and tastes of the natural world change from one season to the next. The book is aimed at parents, grandparents, classroom teachers, outdoor educators and youth leaders of all kinds. Much of the information – and many of the activities – will also be of interest to adults, especially if you need to brush up on your own nature skills. Adults should also be interested in the extensive background information on evolution, citizen science projects, nature journaling, nature photography and how to make the most of digital technology,

The Big Book of Nature Activities

The Big Book of Nature Activities

Introduction

We begin the book by discussing the disconnection from nature that characterizes so much of modern society. In an increasingly urbanized world, our children are much more likely to experience the flickering a computer screen or the sounds of traffic than the rhythmic chorus of bird or insect song. And sadly, they can more easily identify corporate logos or cartoon characters than even a few tree or bird species. We therefore ask the questions: Where will tomorrow’s environmentalists and conservationists come from? Who will advocate for threatened habitats and endangered species? What are the impacts on one’s physical and emotional well-being from a childhood or adulthood spent mostly indoors? We then go on to discuss some of the consequences of what the environmental educator Richard Louv calls “Nature Deficit Disorder”.

The activities, species and events in nature, which are described in the book, cover an area extending from British Columbia and northern California in the west to the Atlantic Provinces and North Carolina in the east. This includes six ecological regions such as the Marine West Coast and the Eastern Temperate Forests. In other words, the book applies to most anywhere in North America where there are four seasons.

The introduction also provides ideas on how to raise a naturalist (hint: take your kids camping!), how to get kids outside, how children of different ages respond to nature, how nature can enhance our lives as adults and the importance of being able to identify and name the most common species. We provide lists of 100 continent-wide key species to learn – everything from birds and invertebrates to trees, shrubs and wildflowers – as well as about 50 key regional species. We also introduce the reader to three cartoon characters, namely Charles Darwin, Carl Sagan and Neil DeGrasse Tyson who will tell stories of the wonder of evolution and the universe throughout the book.

Charles Darwin cartoon character - Kady MacDonald Denton

Our Charles Darwin cartoon character gives examples of the wonder of evolution throughout the book – Kady MacDonald Denton

Basic Skills

Connecting to nature is easier when you have learned some basic skills. In this section, we provide hints for paying attention (be patient and slow down), how to engage all the senses (learn to maximize your sense of smell), how to lead a nature hike (have some “back-pocket” activities ready to go), nature-viewing and traveling games from a car or school bus (do a scavenger hunt), how to increase your chances of seeing wildlife (try sitting in one place), how to bring nature inside (set up a nature table), how to get involved in “citizen science” (start at scistarter.com) and how to connect with nature in the digital age (make the most of your smartphone and social media). The latter section is especially detailed. Although it might seem counter-intuitive, there are actually many ways in which digital technology can inspire people of all ages to explore nature and share their experiences with others.

We also provide information on the basics of birding; insect-watching (butterflies, dragonflies, damselflies and moths), plant identification, mushroom-hunting, getting to know the night sky, nature journaling, nature photography, and nature-based geo-caching. Additional basic skills are covered in the activities in the seasons chapters themselves. These include fish-watching, mammal-watching, amphibian- and reptile-watching and tree identification.

Key Concepts

The third chapter in “The Big Book of Nature Activities” deals with four important concepts, which help us to more fully understand and appreciate nature. We start by explaining why we have seasons, and how the tilt of Earth’s axis makes all the difference. This is followed by a discussion of phenology, which is the science of observing and recording “first events”- such as spring’s first lilac bloom or frog song. Next, we talk about how climate change is affecting different habitats and species, and why a connection with nature is so important in light of this threat. Finally, we discuss the importance of understanding evolution and how it is manifested in even the most common backyard species. Armed with a little knowledge of evolution, we can learn to appreciate the wonder that resides in all species, not just the charismatic ones. We also want children to know that science is just beginning to unravel many of the mysteries of evolution and the incredible stories it has revealed. Our Darwin cartoon character tells many of these stories. The good news for young scientists-to-be is that there’s so much we don’t yet understand

The book explains the basics of evolution and natural selection, without getting into the details of genetics. We then provide a story for young children on how evolution might work within a population of imaginary sand bugs. For older children and adults, we go on a “field trip of the imagination” in which we visit our ancestors, starting with our self, our grandfather, our great-grandfather, etc. and ending up at our 185-million-greats-grandfather who, by the way, would have been a fish! This section concludes with a shortened version of Big History, the evidence-based story that takes us from the Big Bang to the present, in which we humans are “star stuff pondering stars”.

The book contains over 400 illustrations.

Hundreds of drawings

 Seasons’ chapters

The four seasons’ chapters make up the heart of the book. Each begins with a summary of some of the key events in flora, fauna, weather and the sky. This includes events that occur across North America as well as happenings that are specific to each region. Most of the activities in the chapter relate to these events. This is followed by a seasonal poem to enjoy and maybe memorize; suggestions for what to display or collect for the nature table;

ideas about what to photograph or record in your nature journal; a short seasonal story called “What’s Wrong with the Scenario” in which you try to spot the mistakes; the story of Black Cap, the Chickadee, which takes you through a year in an individual chickadee’s life and includes activities; and ideas for what to do at your Magic Spot, a special nature-rich area close to home.

The final and largest section of the seasons’ chapters is called “Exploring the season: Things to do.” It comprises 50 or more activities to activate your five senses, keep track of seasonal change, explore evolution, and have fun discovering fascinating aspects of birds, mammals, reptiles, amphibians, fish, invertebrates, plants, fungi, weather and the night sky. We also offer up suggestions on how to make nature part of seasonal celebrations like Thanksgiving. Some of the activities include making a scent cocktail and touch bag, using a roll of toilet paper to create a history-of-life timeline, meeting the “beast” within you, a non-identification bird walk, a woodpecker drumming game, mammal-watching with a trail camera, observing spawning salmon, a frog song orchestra, exploring seaside beaches and tide pools, a “bee dance” drama game, conducting a pond study, “adopting” a tree to observe over an entire year, dissecting flowers, a fungi scavenger hunt, a classroom “hand-generated” thunderstorm, going on a night hike, making tin can constellations, creating your own moon phases, celebrating the winter and summer solstices, ideas for Earth Day, and more. Scattered throughout the activities are suggestions for getting involved in citizen science projects. The book concludes with an appendix with blackline masters for photocopying and a detailed index.

There are 16 pages of colour photos that link to some of the activities.

Sixteen pages of colour photos that link to some of the activities.

The book also contains several hundred drawings, most of which were done by talented Lakefield artist, Judy Hyland. Others were contributed by Kim Caldwell, Kady MacDonald Denton, Jean-Paul Efford and Heather Sadler (drawings by her late father, Doug Sadler). In the middle of the book, you will find a 16-page block of colour photos by the authors and others.

“The Big Book of Nature Activities” is available at Happenstance Books and Yarns at 44 Queen Street in Lakefield (705-652-7535), at Camp Kawartha (1010 Birchview Road, Douro-Dummer), at Chapters (Landsowne Street west in Peterborough) and online at Chapters.Indigo.ca and Amazon.ca. It would make a great end of school year gift. The cost is $39.95. A book launch hosted by Happenstance will be held on July 24, from 2-4 p.m. at the Camp Kawartha Environment Centre at 2505 Pioneer Road. For more details and regular updates about the book, please go to drewmonkman.com. The authors can be reached by email at dmonkman1@cogeco.ca and jrodenburg@campkawartha.ca

 

 

 

 

Mar 032016
 

Seeing exciting new plants and animals often requires effort – maybe rising at dawn and setting off on a long hike or driving for hours to some far-flung destination. Getting easy, close-up looks at iconic species right in the heart of a metropolis is therefore quite a treat. Such was our experience in a two-week trip to the San Francisco and Monterey areas. It was heartening to see how well species ranging from sea otters and elephant seals to monarch butterflies and spotted owls are doing in such a populated area of California.

We rented the ground floor of this beautiful old Mill Valley home on the side of Mt. Tamalpais (Photo: Drew Monkman)

We rented the ground floor of this beautiful old Mill Valley home on the side of Mt. Tamalpais (Photo: Drew Monkman)

This was our first visit to the Golden State. My wife, daughter and I took advantage of a family wedding to make an extended stay and explore some of California’s fascinating nature, culture and history. For the first five days, our home base was Mill Valley, a lovely town located just north of the Golden Gate Bridge and set in picturesque wooded canyons. From the house we rented high on Mount Tamalpais, we awoke each morning to beautiful sunrises over the fog-covered valley and San Francisco Bay. Ravens and red-tailed hawks soared constantly overhead, their calls an unbroken presence. Anna’s hummingbirds darted among the blossoms in the garden, stopping from time to time to perch on an orange tree, while white-crowned and golden-crowned sparrows foraged on the ground. A dense forest of coastal redwoods bordered the property, providing both privacy and a sense of connection with an older, wilder California. The air was replete with the smell of the white jasmine vines that adorned the deck. The roadside down to Mill Valley was bordered by yellow-flowered acacia trees, interspersed among lofty, fragrant eucalyptus.

Sunrise over Mill Valley and San Francisco Bay (Photo: Drew Monkman)

Sunrise over Mill Valley and San Francisco Bay (Photo: Drew Monkman)

Nearby Sausalito, famous for its houseboats and upscale hillside homes, was also a delight. Harbour seals and sea lions hunted just offshore, attracting hoards of western and California gulls each time they surfaced with food. Brown pelicans glided low above the water while loons, grebes and cormorants dove for food further out in the bay. Alcatraz Island and the imposing skyline of downtown San Francisco loomed in the distance.

San Francisco

Following a great four-hour  guided tour of San Francisco to get our bearings, we returned to the City by the Bay to wander its charming neighbourhoods like Pacific Heights and Russian Hill. Everywhere we walked – often huffing and puffing on the ridiculously steep hills – the streets were bordered by beautiful, pastel-coloured houses, many of Victorian style but none exactly alike. Bushtits, white-crowned sparrows and Oregon dark-eyed juncos flitted among the shrubs and trees of house-front gardens where red-flowered camellias, magnolias, candelabra aloes, and plums were in full bloom. The parade of different scents, too, was intoxicating. San Francisco is pursuing an ambitious urban forest plan, which was evident by the huge number and variety of new trees planted along the sidewalks. Many of them had watering bags zipped around the support posts.

Magnolia in full bloom (Photo: Drew Monkman)

Magnolia in full bloom (Photo: Drew Monkman)

At Telegraph Hill, a famous San Francisco landmark and site of the Coit Tower, California towhees fed on the ground, while Wilson’s warblers and western scrub jays called from the iconic  Monterey cypress trees. At one point, a flock of red-masked parakeets (also known as cherry-headed conure) passed noisily overhead, making me wonder if I wasn’t somewhere in South America. Native to Ecuador, these birds were released in San Francisco decades ago – probably by frustrated pet owners – and are now reproducing on their own.

On Pier 39, at busy Fisherman’s Wharf, we got close-up looks at a colony of California sea lions, a fixture here since 1989. The Marine Mammal Store and Interpretive Center monitor the sea lion population each day, and educational information is provided to tourists. Sea lions can be distinguished from seals by the presence of external ear flaps and their ability to walk on land. Seals only have ear holes and move on land by flopping on their bellies.

 

Golden Gate Park

The crown jewel for exploring nature in San Francisco is Golden Gate Park. At five kilometres long and a kilometer wide , it is 20 percent larger than Central Park in New York. We spent an afternoon touring the park by bicycle. In addition to native trees like coast redwoods, Douglas fir and Monterey cypress, numerous non-natives like eucalyptus border the streets, pathways and meadows. It was hard to bike very far without stopping to take a picture or to grab our binoculars. The park contains a chain of lakes where we spotted a  variety of waterfowl, including ruddy duck, American wigeon and bufflehead. Wading birds like green herons and both snowy and great egrets were common, too. Along the trails, black phoebes, Brewer’s blackbirds, chestnut-backed chickadees and the ubiquitous white-crowned and golden-crowned sparrows popped up continuously.

A must-see for anyone visiting the park is the 55-acre San Francisco Botanical Gardens. We spent most of our time exploring the California Natives and rhododendron sections, where dazzling pink and white magnolias were in blossom. The California section provides a great overview of the state’s flora and was our introduction to species such as manzanitas, madrone, live oaks, Ceanothus, California buckeye, and California bay laurel. We also enjoyed  an interpretive trail that takes you through the story of plant evolution, from the spore-bearing plants of the Devonian period to the flowering plants of the Eocene.

Monterey Cypress in Golden Gate Park (Photo: Drew Monkman)

Monterey Cypress in Golden Gate Park (Photo: Drew Monkman)

At the end of the trip, I also spent several hours at the California Academy of Sciences. It is one of the largest museums of natural history in the world, housing over 26 million specimens. Completely rebuilt in 2008, the museum is at the forefront of environmentally friendly design. Most impressive is the  two and a half acre  green roof, which is planted with over a million California native species. A huge glass dome encloses a living rainforest, and the aquarium section includes a living coral reef, tide pool and the underwater ecosystems of the California coast. The Africa Hall has a fascinating exhibit on human evolution, while the earthquake section explains how seismic activity and plate tectonics has shaped both California and the world. There is also a superb exhibit on the role colour plays in nature, a naturalist centre, and docents to answer questions and provide hands-on experiences with many species. Along with the botanical park, the museum serves as a great introduction to the natural history of the state.

Muir Woods

Before we left Mill Valley, we paid a much-anticipated visit to nearby Muir Woods National Monument. The park protects 554 acres of old-growth coastal redwood forest. The trees are often  shrouded in  fog, which provides up to half of their water needs. Related to the giant sequoia of the Sierra Nevada, many of the trees are over 200 feet tall and between 500 and 800 years old. Other common trees include California bay laurel, bigleaf maple and tan oak. The forest is also home to northern spotted owls, which appear to be thriving.

Walking through the towering redwoods of Muir Woods (Photo: Drew Monkman)

Walking through the towering redwoods of Muir Woods (Photo: Drew Monkman)

By arriving early on a weekday, we had the trails mostly to ourselves and could enjoy the calls of Steller’s jays and the remarkably long, tinkling trills of the Pacific wren. The forest  floor was carpeted with horsetails, ferns and blooming redwood sorrel, interspersed here and there by Western trilliums, fetid adder’s tongue and  vermillion cap mushrooms. We were also fascinated by the eight-inch banana slugs that glided across the forest floor.

The park is named after naturalist John Muir who once wrote, “This is the best tree-lover’s monument that could possibly be found in all the forests of the world.” His efforts to preserve the natural landscape of America earned him the title “Father of the National Park System.”

Later the same day, we made a short but beautiful drive to Stinson Beach on the Pacific coast. In addition to spectacular  scenery, the beach is home to overwintering shorebirds like marbled godwits and willets. As we walked along the sand, we also got great views of Heermann’s gulls, resplendent in their dark grey  breeding plumage. This area is also an overwintering site for monarch butterflies. With temperatures of over 20 C, the butterflies had already begun to disperse. We watched as dozens flew about in pairs, some stopping to mate on the grass. Instead of going to Mexico, the monarch population west of the Continental Divide fly to the coast of California to spend the winter. They cluster together by the hundreds or even thousands on the branches of pines, cypress and eucalyptus trees.

The San Francisco area was just a foretaste of the natural wonders we were to experience in California. The second week took us south to the Monterey-Big Sur area and then north again to Point Reyes National Seashore. More about these next week.

 

 

Feb 182016
 

Even people who don’t like winter will grudgingly admit “well, at least, there’s no bugs.” Guess again. Insects are indeed out and about in the winter woods. The good news, however, is that the species you’re most likely to encounter ‑ the minuscule snow flea ‑ has no interest in humans. Even better, like the return of cardinal and chickadee song, its presence is a sign that spring is fast approaching.

The snow flea (Hypogastrura nivicola) is not related to true fleas such as those your dog or cat might bring home

Snow fleas in a deer track - Sheba Marx

Snow fleas in a deer track – Sheba Marx

. It belongs to an ancient group of wingless invertebrates called Collembola, commonly known as springtails. Along with other species of springtails, snow fleas are among the most abundant insects known to science. Tens of thousands can be found in a square metre of soil. For most of the year, they live beneath the forest floor, dining on algae, leaf mould and other fungi. They are part of a group of organisms known as decomposers, which turn organic material into soil nutrients that are essential for plant growth. This, in turn, allows other animals to feed on the plants, which are the foundation of the food chain.

On mild, mid- to later winter days, snow fleas take advantage of the melted area around the base of trees to spread out on the surface of the snow. They will also make their way to surface via the deep tracks of deer. I often see them on or adjacent to the trails of the Kawartha Nordic Ski Club on Highway 28, near Haultain. They sometimes congregate in such numbers as to turn sections of the trail black. If you crouch down for a closer look, what initially appears like particles of soot or pepper will start jumping about in front of you, often completely disappearing from view.

Olympic jumpers

Only about 1 mm in length, snow fleas accomplish their incredible leaps thanks to a forked appendage called the furcula, which is attached to the tip of the abdomen. Most of the time, it is folded under the abdomen and held in place by a tiny latch, or tenaculum. When the snow flea decides its time to move, it arches its body, thereby releasing the latch. Loaded with elastic energy, the furcula swings down and sends the tiny insect catapulting skyward. It can, in fact, hurdle itself an amazing 13 centimetres, which represents 65 times its body length. In human terms, that’s like being able to jump the length of a football field!

How do they survive?

Insects are exothermic, which means that their body temperature and activity level depend on the air temperature. The cold usually renders them inactive. The snow flea, however, has overcome these limits and thrives in sub-zero environments. First of all, its black coloration allows efficient absorption of heat from the sun. The microclimate in the sheltered spaces between the ice crystals is also substantially warmer than the surrounding air. In addition, four hundred million years of evolution have allowed snow fleas to produce a kind of natural anti-freeze. Researchers at Queen’s University have actually synthesised this protein, which is unlike any other previously known to science. They hope that similar proteins may be used for storing transplant organs. By preventing the formation of ice crystals in tissues, organs could be stored at lower temperatures and therefore remain available for transplants over longer periods.

Mysteries remain

What are snow fleas doing out on the snow, when most self‑respecting insects are overwintering as eggs, larvae, pupa or inactive adults? It was once thought that they emerged to feed on microscopic algae, bacteria and fungi on the snow’s surface. This, however, has been disproved. A new hypothesis is that by late winter they have reproduced to a point where space is at a premium. The overcrowding means that some have to escape to the surface, where they simply wander around aimlessly until colder temperatures force them back under the snow and into the soil.

There is also some doubt whether snow fleas are even insects. Their primitive anatomy has much in common with hexapods, an even more ancient group of invertebrates from which insects are believed to have evolved. Like countless other areas of science, so much about snow fleas remains shrouded in mystery.

Stoneflies

Another insect to watch for at this time of year is the winter stonefly. On mild, sunny days, adult stoneflies can be seen crawling over the snow in areas close to running water. They are weak fliers and do not stray far from the water’s edge. Like gray squirrels, skunks and great horned owls, stoneflies seek out partners early in the season to beat the spring mating rush. After mating, the female returns to the frigid water of the stream to lay her eggs.

Stonefly (note tail-like appendages) Wikimedia

Stonefly (note tail-like appendages) Wikimedia

The stonefly’s life cycle is quite unusual. After the eggs hatch in the spring, the larvae bury themselves in the mud of the streambed, where they lie dormant all summer. In this way, they avoid dangers such as fish predation, low summer oxygen levels and fluctuating water flows. They emerge from the mud in late November, grow quickly into the adult stage and are ready to mate by mid‑winter.

One species commonly seen along Jackson Creek in Peterborough is the small winter stonefly (Capnis genus). I often find them on the snow adjacent to the creek. This stonefly is black, measures about eight millimetres in length, and folds its wings flat over its back. It has two prominent tails (cerci). Since stoneflies require clean, moving water to survive, their presence is usually an indicator of good water quality. In some jurisdictions, winter stonefly numbers are closely monitored to gauge the health of rivers and streams.

There are a couple of other insects to watch for if you’re out in the woods this winter. Snow scorpionflies (Boreus brumalis), dark-bodied insects about seven millimetres in length, are active on mild winter days. Look for them on or near the moss in which they develop. Males have only rudimentary wings, while females have no wings at all. The latter have a prominent ovipositor, however, which is used for laying eggs.

Near streams, keep an eye open for the wingless winter crane fly (Chionea genus). At first, you may dismiss it as a lost spider, but a quick count of the legs ‑ six instead of eight ‑ will prove that it is indeed an insect. Its dark‑brown colouration makes the winter crane fly easy to see against the snow. You may be familiar with the crane flies we see in summer. They look like giant mosquitoes with a wingspan of about three centimetres and extremely long legs. The winter crane fly has evolved as a wingless, smaller‑sized version of its summer cousin with special adaptations to winter life.

To the curious and mindful observer, there is far more going on in the winter woods than first meets the eye. As with so much in nature, it’s mostly a matter of being patient and paying attention.

 

 

 

Feb 072015
 

In a cave, tunnel or old mine near you…nothing is stirring. Some of our most fascinating animals survive the cold of winter by hibernating. They enter a deep torpor, a kind of suspended animation. By allowing their body temperature to fall dramatically they reduce their metabolism to a level at which it is just ticking over, slowly consuming stored fat reserves as they wait for spring. Bats are among the animals that adopt this strategy. Since all Canadian bats are insectivorous it is no surprise that they have evolved to do this since there is precious little for them to eat during the winter. Some of our local bats prolong their feeding opportunities by migrating further south before hibernating and a few of our larger tree-roosting species may keep the need to hibernate to a minimum by flying as far south as Mexico. Many other bats are quietly hibernating right here in Peterborough County. Hibernating bats need cool, frost-free, stable conditions where humidity is high and they are safe from the attentions of potential predators. Caves, old mines, tunnels and other sites offering these conditions suit them best.

Like us, bats are mammals and so are warm-blooded creatures. While they are active, bats maintain a core body temperature very similar to our own, around 35oC to 37oC, but unlike us, they can allow their body temperature to fall during periods of inactivity and so conserve energy. They can do this at any time of the year, but during the winter this torpor becomes their long-term condition. Hibernating bats are largely inactive with only basic body functions operating at a level to keep them alive. They will occasionally wake up, use their fat stores to quickly raise their body temperature back to normal levels and then go in search of a drink to avoid death by dehydration. During these periods of wakefulness some male bats will also take the opportunity to mate with unaware, slumbering females. The sperm they deposit stays viable until the females become active and ovulate in the spring.

Most bats, including all Canadian species, are very small mammals. The adults of species found locally range from just 3g. to 39g.. It is surprising how long such small animals can live. Some species regularly survive in the wild for over twenty years while animals well into their thirties have been recorded in Ontario. These impressive figures have caught the attention of researchers interested in improving human longevity, since bats have the longest life spans of any mammals in relation to their size. Research shows that the bat species with the greatest life spans produce two specific proteins that may be linked to their longevity Bats are also generally very good at fending off disease so the efficiency of their immune systems is also attracting interest. Unfortunately however, their immune system is not fool proof.

Little Brown Bat with White Nose Syndrome (US Geological Survey)

Little Brown Bat with White Nose Syndrome (US Geological Survey)

Tragically, the last eight years have been a perilous time for our hibernating bats as a new disease has emerged against which they have little defense. In 2006 at a cave near Albany, New York State, bats were found to be sick and dying. Around their muzzles was a growth of a powdery fungus. The new disease became known as White Nose Syndrome. We know now that this fungus, previously unknown to science, originated in Europe and Asia. Bats on those continents can carry the fungus, but do not appear to be made sick by it: they must have evolved immunity to the fungus, possibly over thousands of years. It is assumed that spores of the fungus reached Albany on the clothes or footwear of a visitor to the cave system. Since 2006 the fungus has spread at terrifying speed and is now found in five Canadian provinces, including Ontario and twenty-five US states. It is estimated to have killed well over five million bats.

The White Nose fungus, Pseudogymnoascus destructans, gets into the skin of hibernating bats and disrupts their hibernation cycle. Infected bats wake up repeatedly, causing them to burn up their limited fat reserves and become dehydrated. Researchers with the U.S. Geological Survey and Wisconsin University recently discovered that hibernating bats with the disease use twice as much energy as healthy bats. Additionally, the infected bats show physiological imbalances that could disrupt processes such as as normal heart function. Infected bats will often leave their hibernation site in search of water and needlessly use up stored energy in a futile attempt to feed. Five of the eight species found in Ontario are thought to be vulnerable to the disease and the vast majority of infected bats die. The Little Brown Bat, formerly by far the most common bat in this part of the world, is one of the most hard-hit. The fungus is transmitted primarily from bat to bat and some experts believe it is causing the most dramatic population decline ever witnessed in mammalian populations anywhere in the world. Fortunately the fungus does not appear to pose a risk to humans, pets or livestock.

Bats consume vast quantities of insects, including mosquitoes and pests of agriculture and forestry, so the ecological and financial impact of losing so many bats to White Nose Syndrome is expected to be considerable. It is thought to have already cost agriculture many millions of dollars in extra pesticides to cope with the rise of pest populations that bats would previously have suppressed. Canadian crops most likely to be hardest hit include wheat, barley, corn, oats, canola, flaxseed, and other oilseeds. The loss of bats from natural food webs will also have unforeseen consequences as some species suffer as a result of the loss and others exploit the decline in bat numbers.

In response to the White-Nose crisis the federal government has added three species of bats to the List of Wildlife Species at Risk in Canada (also known as Schedule I of the Species at Risk Act). These three bats species – the Little Brown Bat (Myotis lucifugus), the Northern Myotis (Myotis septentrionalis) and the Tri-colored Bat (Perimyotis subflavus) are all found in this area and have been listed as Endangered.

It is believed that some North American bat species may be facing extinction because of White Nose Syndrome. Others may eventually develop immunity, but because most female bats are capable of producing only one pup per year, it may take centuries for their populations to recover. Researchers are desperately trying to find ways to protect bats. They are hoping to find natural agents that may help to rid hibernation sites of the deadly fungus.

A scientist documenting a victim of White Nose Syndrome (US Geological Survey)

A scientist documenting a victim of White Nose Syndrome (US Geological Survey)

What can ordinary people do to help bats? The most important thing is to avoid entering hibernation sites such as caves and disused mines, especially during winter. It is easy to disturb hibernating bats, causing them to unnecessarily use up their stored fat, making them even more vulnerable to disease. If we have to enter such sites we should follow the Ministry of the Natural Environment’s guidelines and take precautions to avoid disturbing bats and spreading fungal spores from one site to another. Unusual bat activity or deaths can be reported to the Canadian Cooperative Wildlife Health Centre (1-866-673-4781) or the Natural Resources Information Centre (1-800-667-1940). We should all do what we can to avoid disturbing bats at any time of year. We should protect their summer roosts in trees, barns, roofs and bridges and help maintain the natural habitats they depend on.

Nov 132014
 

Love them or hate them, nearly everyone has an opinion on Gray Squirrels. Maybe you are the type who adores these animals, feeds them and gives them silly names. On the other hand, you may fall into the camp of those who curse them for eating up the birdseed or digging up the tulip bulbs. Regardless of what you think of them, they are important indicators of the health of local ecosystems. If we have healthy squirrels, we can usually assume that we have healthy trees. Healthy trees, in turn, indicate a generally healthy environment, which of course is good for humans, too.

Black colour morph of Gray Squirrel -Wikimedia

Black colour morph of Gray Squirrel -Wikimedia

Description
The Gray Squirrel’s scientific name is Sciurus carolinensis. Sciurus is Greek for “shadow tail” and refers to the animal’s habit of sitting in the shade of its long, flat, bushy tail. The squirrel uses its tail both as a counterbalance and as a sort of parachute when jumping from tree to tree. As the common name denotes, these squirrels are predominantly grey in colour. Just like people, however, their “hair” colour can vary. In Peterborough, most Gray Squirrels are in fact black. This is not a separate species but rather a genetic variation known to scientists as a “colour morph.” Despite the predominance of black individuals, maybe 10 percent of our local squirrel population is indeed grey. There are also rare instances of a reddish or brownish colour morph, one of which was reported to me recently. You sometimes see combinations of different colours, too. There used to be a squirrel in our neighbourhood that was black with a red tail. Some squirrels also display patches of white. In Exeter, Ontario (50 km north of London), there is even a population of white Gray Squirrels. They are not albinos but are actually colored white or slightly off-white. They have normal colored eyes, unlike the classic red eyes of albinos.

Brown colour morph of Gray Squirrel - Barb Evett

Brown colour morph of Gray Squirrel – Barb Evett

Ecology
Gray Squirrels are essentially vegetarians, although they may sometimes eat insects or even the odd baby bird or egg. In the fall and winter, their favourite foods are wild fruits and seeds, including berries, acorns, walnuts and maple keys. Watch for them high up in Manitoba and Norway maples feeding on the keys. In the spring, their diet turns to tree buds, tree flowers and even Sugar Maple sap. During the summer months, squirrels eat fruits, berries, and succulent plant materials. They are also known to chew the bark from a variety of trees, although the exact reasons for this behaviour are poorly understood.
As anyone who feeds wild birds knows, Gray Squirrels also love sunflower seed, millet and suet cakes. They can provide great entertainment as they try to access a strategically-located feeder or one with a squirrel guard. About the only seeds they usually dislike are safflower seeds. These rodents also have the very annoying habit of digging up bulbs and either eating them or reburying them elsewhere.
Gray Squirrels are scatter-hoarders. This means that they hoard food in numerous small caches, scattered about a given area. Each food item is cached separately in a cup-shaped hole about one inch below ground. The hole is then covered with soil. Over the course of the fall, a single squirrel is estimated to make several thousand caches. In the more permanent caches, the food is not retrieved for weeks or months. Other caches, however, are only temporary and the squirrel may return only hours later and rebury the food item in a more permanent and secure location. If the squirrel senses it is being watched, it will sometimes only pretend to bury the food, all the while concealing the morsel in its mouth.
Gray Squirrels also have an amazing ability to retrieve the food they have hidden. Most importantly, they depend on very accurate spatial memory. This allows them to remember cache locations with respect to distant and nearby landmarks. For example, they may use the relative position of trees and buildings. They can then triangulate, relying on the angles and distances between these distant landmarks and their caches. Once the squirrel is close to the cache, a keen sense of smell helps it find the exact location. Accurate spatial memory is especially important in the winter when caches are often covered with snow and smells are hard to detect. Frequently, however, the food a squirrel finds may actually have been buried by another individual.
Not all hidden nuts are recovered. Some will germinate and grow into trees. This probably explains why you may suddenly find a walnut tree growing on your property, even though there are no mature walnut trees in the immediate area.

Grey colour morph 2 of Gray Squirrel - Wikimedia

Grey colour morph of Gray Squirrel – Wikimedia

Reproduction
Gray Squirrels are able to breed twice a year, once in early spring and sometimes a second time in late summer. In years when wild food is scarce, however, they will only breed in the spring. Mating takes place in January or February, when the females come into heat and give off a scent that the males find irresistible. It is not uncommon to see a group of squirrels streaming by in a treetop chase as three or four males chase a half-terrorized female. Some amazing acrobatics are usually part of the show.
Tree cavities are the Gray Squirrel’s preferred nesting site. However, they will also construct a leafy nest in the fork of a large tree. Slightly larger than a basketball, the tree nests or “dreys” consist of an outer shell of leaves and twigs and a cozy inner chamber lined with mosses, grasses, shredded bark, and sometimes even cloth or paper. During cold winter weather, the dreys also provide shelter for the squirrels, and several individuals may snuggle up together. Dreys are most commonly seen in cities – probably because tree cavities are less common – and are especially evident near the tops of large maples. It is not uncommon to see five or six dreys in the same tree. It should also be noted that Gray Squirrels will also sometimes nest in the attic or exterior wall of a house.

Squirrel drey -Drew Monkman

Squirrel drey -Drew Monkman

Other behaviours
Here are some other interesting Gray Squirrel behaviours to watch and listen for:
• Leaping up trees; not climbing.
• Coming down a tree head-first, something very mammals are able to do. The squirrel achieves this by rotating its back paws 180 degrees, so that the claws are pointing up the tree instead of down. This allows the animal to firmly grip the tree bark.
• Using vocalizations and tail flicking to communicate. One of the most common sounds that Gray Squirrels make is a loud “kuk.” The sound is produced in conjunction with tail flicking and is used to ward off predators or warn other squirrels of a predator’s presence.
• Entering or exiting a drey. This is something I have yet to see myself. I would love to hear from anyone who witnesses this.
• Flattening out its body against a tree trunk or tree limb and remaining motionless. This is sometimes done in situations where danger threatens, but the squirrel decides against running away. Sometimes, a squirrel will also move inconspicuously around the trunk of the tree, keeping just out of sight of the predator or intruding human.
It is important not to take Gray Squirrels for granted or to demonize them. Because they are common in urban areas and are active during the day, squirrels are the wild mammals that many of us encounter most. The next time they visit your yard, take some time to really watch them. Encourage your children or grandchildren to do the same. Like everything in nature, they are far more fascinating than you might ever think.

 

Oct 232014
 

For some people, the natural world can be an intimidating place. Although it might seem illogical to be afraid of a tiny creature like a spider or bat, we can’t deny that some animals do indeed elicit a fear response. With Halloween upon us, what better time to talk about fear of the natural world, be it anxiety at the sound of thunder or revulsion at the sight of a spider running across the bathroom floor.
An aversion to particular animals was almost certainly critical to the survival of early humans. As much as being too fearful would have made survival difficult, insufficient fear would have led to reckless behaviour and possibly death. In the 21st century, however, you can still have these feelings of angst and at the same time experience a deep appreciation and respect for the animal in question. Stephen Kellert, author of “Birthright: People and Nature in the Modern World” says that: “While aversive emotions towards (certain) animals are typically strong, they can also be positively channeled into fascination, curiosity and exploration.” For example, a fear of snakes or wolves doesn’t have to provoke destructive behaviours.
When I was teaching, I always made of point of encouraging my students to hold or touch the many animals that visited our classroom or that we encountered outside. However, there was always the odd student who would refuse to do so. I would sometimes be a little facetious and say something like: “Did you have a bad experience with a snake once and get bitten?” Never was this the case. So, where do fears like this come from and what are we to make of them?

Eastern Hog-nosed Snake  (Joe Crowley)

Eastern Hog-nosed Snake (Joe Crowley)

Snakes – Approximately one adult human in three suffers to some degree from ophiophobia, a fear of snakes. Some people are afraid of even thinking of snakes or looking at images of them. This fear may be an inherent reaction, however, and we aren’t alone in this regard. An innate fear of snakes is present even in our closely-related primate cousins, the monkeys. In one famous experiment, monkeys literally panicked when suddenly exposed to snakes, even though they had been raised in a laboratory and had never seen these reptiles before.
Snakes and early primates may have been involved in an evolutionary “arms race” of sorts. According to Lynne Isbell, an anthropologist at the University of California, the survival of early primates depended to a large extent on ways to detect and avoid snakes. Fossil and DNA evidence suggests that the snakes were already around when the first primates were evolving some 60 million years ago and were among the first serious predators our ancestors faced. Early primates were adapted to living in trees, searching for food at night and sleeping in the canopy during the day. Snakes slithering through those trees would have been a constant threat. This may explain the evolution in primates of adaptations such as a better eye for colour, detail and movement. All of these abilities would have been very important for detecting threats at close range. To keep up with primate evolution, snakes had to get better at killing their prey. This may have driven the evolution of venom, according to Isbell.

Bats – A fear of bats may simply be related to the natural startle response experienced by an unsuspecting person when a bat somehow finds itself into a house and flies about erratically looking for a quick exit. Tied to this are vague notions of these flying mammals getting caught in your hair (never happens) or that most bats have rabies, which isn’t true either. Even among sick bats submitted for rabies testing, only a tiny percentage ever test positive, and those that do are usually clumsy, disoriented, and unable to fly. We should also remember that you can only get rabies if a rabid animal bites you. Contrary to a widespread misconception, only three species of bats feed on blood – mostly livestock – and these species all live in Latin America. In fact, the majority of bats are terrified of humans and see man as a potential predator.

Little Brown Bat (with WNS) Wikimedia

Little Brown Bat (with WNS) Wikimedia

If anything, we should be afraid FOR bats, not of them. White-nose syndrome (WNS) named for a distinctive fungal growth around the muzzles and on the wings of hibernating bats, has resulted in the deaths of at least 6 million North American bats. In fact, the once-abundant Little Brown Bat is expected to go extinct in the wild. In Ontario, it is now on the list of endangered species. In the seven years since WNS first showed up, Ontario’s bat population is estimated to have dropped by over 90 per cent. This is an extinction tragedy of unprecedented proportions. You don’t have to find bats warm and cuddly to feel great sadness in the crisis they are now facing. Their disappearance is making the natural world a lonelier and less fascinating place.
Wolves – When it comes to the complicated relationship between fear and fascination for a wild animal, there are few better examples than the wolf. Wolves used to be universally reviled and many people wanted to annihilate them altogether. Yes, they may have represented a real danger to our distant ancestors. In modern times, however, wolf persecution is more closely linked to reasons such as livestock depredation. Thankfully, attitudes towards wolves have now shifted dramatically. Much of this has to do with a growing understanding of wolf biology and the huge ecological value of these animals. When wolves are behind bars in a zoo or wildlife park, however, and any element of danger has disappeared, the sense of wonder they inspire falls precipitously. That is why having healthy populations of wild wolves is so important.
Invertebrates – Bugs – to use the vernacular – seem to attract an especially widespread aversion. It’s true that a healthy respect for wasps, leeches, spiders and similar creatures is a useful trait, since it helps us to avoid pain and disease. There are certainly deeper psychological reasons, too, for a dislike of “creepy crawlies.” Their lack of feeling and reason is a probably a big part of it. As Kellert writes: “All they seem to have in common with us are vaguely familiar body parts and a passion to survive and reproduce.” Despite this innate dislike on the part of many people, it’s still possible to learn to respond to these creatures with curiosity and a sense of wonder. There is still so much we don’t know about the invertebrate world. An entire scientific career awaits curious, young researchers.

Black and Yellow Garden Spider (Argiope aurantia) Wikimedia

Black and Yellow Garden Spider (Argiope aurantia) Wikimedia

So, what should we be afraid of in 2014? I would argue that climate change should be near the top of any list. It’s clear that living in a highly technological society where so much of nature has been subdued has greatly reduced our fear of extreme weather. This may partly explain why we continue to engage in the dangerous behaviour of pouring ever-greater amounts of greenhouse gases into the atmosphere. This is why I was so discouraged last week by the cries of joy when the cost of gasoline plummeted. Why aren’t more people joining the dots linking low fuel prices, increased consumption, increased greenhouse gas emissions and accelerated disruption of the climate? Evolution, however, never prepared us for slow-motion threats like climate change. We’re much better at reacting to something like the Ebola outbreak where the impact is immediate and dramatic.

Sep 182014
 

Over the past few years, I’ve become increasingly interested in how to make people more aware of evolution and how it manifests itself in even the most common backyard species. The evolutionary “story” of the Monarch is every bit as compelling as that of the whale. Understanding how the pressures of the environment have shaped the behaviour and appearance of plants and animals – through the process of evolution – adds a great deal to our enjoyment of nature. Little by little, all of the life that surrounds us becomes far more interesting and wondrous.
A focus on the wonder of evolution will be a big part of the up-coming nature activity book that I’m writing with Jacob Rodenburg of Camp Kawartha. This week, I would like to share a few examples from the book that deal with this important theme.

The imaginary Deeg (Wikimedia)

The imaginary Deeg (Wikimedia)

Can you Deeg it?
Here is a story to help kids better understand how evolution works. We’ll see how small mutations (mistakes or errors in the genes) can lead to big changes – so big that one species can even split into two. How? Let’s imagine a species of deer-like animals that live in a grassy valley. We will call them Deegs. Male and female Deegs can breed (have babies together) because they are members of the same species and find each other attractive.
However, let’s see what happens when some of the Deegs are forced to move into a nearby, but isolated, valley. Imagine, too, that instead of tender grasses to eat, there are only trees with tough, leathery leaves. An ability to eat and digest grasses is essential for survival in the original valley but being able to reach up, then chew, and digest tough tree leaves is necessary in the second.
Slowly, over many generations, differences would start to appear in the Tree Valley Deegs, because of mutations. Natural selection – “nature” deciding who will survive – would favour any Deegs that are born with bigger and tougher teeth and mouths as well as longer necks. In other words, Deegs with these characteristics would have a better chance of surviving and passing on their genes.
Now imagine that once every few generations a Deeg from one valley wanders into the other valley and wants to mate. For many years, mating would be possible because they would still be the same species. However, as the generations go by and differences in the genes continue to build up, it would become harder and harder for the Deegs from the two valleys to produce healthy babies together. For example, female Deegs from one valley may no longer find the males from the other valley attractive and refuse to mate. When it becomes virtually impossible for the Deegs from one valley to breed with the Deegs from the other valley, they would have evolved into two distinct species.

Leaves = evolution!
September is a month when our attention is drawn to the beautiful colour display of leaves. For much of the year, however, leaves can easily be taken for granted. To help children appreciate just how amazing these structures really are, ask them to look closely at a tree leaf, to feel it and to describe it. Then, ask some of the following questions:
• Why does a tree have leaves? (to capture sunlight and take in carbon dioxide and in order to use photosynthesis to make the food it needs to grow)
• Why are leaves green for most the year? (green is the colour of chlorophyll, the pigment or molecule that absorbs the sunlight used in photosynthesis)
• Why do leaves change colour? (as summer ends, the chlorophyll in the leaf decomposes and other pigments – e.g., yellow, orange, brown – that were previously hidden become visible)
• What are some of the challenges or problems a leaf faces? (getting eaten, drying out, over-heating from exposure to the sun, etc.)
• Why do you think these pine leaves (needles) might be so hard and waxy? (conserve water, deter insects)
• Why do you think some leaves are so fuzzy or leathery? (conserve water, deter insects)
• Why do leaves come in different sizes? (small leaves conserve water better and don’t heat up so much in the sun; large leaves gather more light and therefore necessary in shady areas or low down in a tree)
• Why do leaves come in different shapes and have different edges? (complex edges and lobes allow leaves to get rid of absorbed heat more quickly; smooth edges are more common in shade-loving plants since heat absorption is less a problem)

Oak leaves - Evolution has made them deeply lobed and leathery. (Drew Monkman)

Oak leaves – Evolution has made them deeply lobed and leathery. (Drew Monkman)

Viceroys and monarchs
The next time you think you’ve see a Monarch butterfly, be careful that you are not actually looking at its look-alike cousin, the Viceroy. These two species have evolved near-identical wing colours and patterns. However, they are only distantly related. The reason they look so similar is because of mimicry, which is the ability of a species to imitate something other than what it really is. Why would mimicry have evolved? In the case of the Viceroy, the purpose is to trick predators into thinking that it is an inedible species. Predators quickly learn that Monarchs are distasteful and eating them causes vomiting. They therefore learn to avoid them. Viceroys therefore find protection by closely resembling their distant cousins. However, there is also some newer research showing that the Viceroy itself may actually be poisonous and that both the Viceroy and Monarch mimic each other. Now, isn’t evolution amazing!

Monarch (left) and Viceroy Comparison - Can you see the difference on the lower (hind) wing? Wikipedia

Monarch (left) and Viceroy Comparison – Can you see the difference on the lower (hind) wing? Wikipedia

BIG IDEA: Metamorphosis
The Monarchs that we see flying south in September have just recently completed an amazing transformation known as metamorphosis. This is the process by which an animal continues to develop and change its body structure and behaviour, even after hatching out of the egg. Some animals that undergo metamorphosis include amphibians, insects, molluscs and crustaceans. In insects, metamorphosis can be incomplete or partial (egg, nymph, adult) or complete (egg, larva, pupa, adult).
In incomplete metamorphosis, the immature stages are called nymphs. Nymphs closely resemble adults but are smaller and lack wings. Some common insects that go through this kind of metamorphosis include grasshoppers and dragonflies. This type of metamorphosis evolved first and is therefore much more ancient than complete metamorphosis.
In complete metamorphosis, the immature stages are called larva. Depending on the insect group, other terms such as caterpillar, grub, maggot, etc. are also used. Unlike nymphs, larvae look very different from adults. Larvae eventually enter an inactive or resting state known as a pupa. In the case of butterflies and moths, we often use the terms ‘chrysalis’ and ‘cocoon.’ During pupation, adult body structures replace the larval structures. The adult emerges from the pupal stage.
Metamorphosis has long been a cause of misunderstanding and mysticism. One early scientist even thought that metamorphosis in butterflies began by the accidental mating of two different species: one, an earth-bound crawler and the other, an airborne flitter! Scientists now use the theory of evolution to explain how a larval and pupal stage came to be. They believe that the larval stage is actually a walking form of the embryo that was developing in the egg. Rather than continue to develop in the egg, natural selection found it to be more advantageous to the animal to get out of the egg as soon as possible and simply to continue to develop while on the move. Scientists think of the pupa as very similar to the nymph stage in incomplete metamorphosis. The difference, however, is that the pupa goes through all of the nymph stages while resting and being completely immobile.

Monarch caterpillar (larva) - Drew Monkman

Monarch caterpillar (larva) – Drew Monkman

CLIMATE CHANGE RALLY
A Climate Change Rally will take place at Millennium Park on Sunday, September 21, from 1:30 to 2:30 PM. The goal of the Rally is two-fold: to explain the impacts climate change is already having right here in the Kawarthas and to encourage local, provincial and federal politicians to take decisive action to mitigate the problem. The event is being organized by the Peterborough chapter of For Our Grandparents and is part of the Purple Onion Festival.

 

Aug 142014
 
Yellowjackets drinking nectar on a flower (Bob Peterson photo)

Yellowjackets drinking nectar on a flower (Bob Peterson photo)

As pleasant as a late summer picnic might be, there always seems to be a handful of unwanted guests. Like corn-on-the-cob, tomatoes and blueberry pie, hornets and yellowjackets are often part of a late summer outside meal. They would be little more than an annoyance if it wasn’t for the fact that they can deliver a painful sting.
People often refer to all black and yellow stinging insects as “bees.” However, bees have a more robust build than wasps and are quite hairy. Their hind legs are flattened for collecting and transporting pollen. Wasps, on the other hand, have a slender body with a narrow waist, more cylindrical legs and appear smoothed-skinned and shiny.
Yellowjackets and Bald-faced Hornets are the most common types of wasps that we encounter in the Kawarthas. They are both members of a family of insects known as the Vespidae, which, in turn, is part of the much larger order Hymenoptera, or bees, wasps and ants. Most of the Vespidae are social wasps that nest in colonies. The terms “hornet” and “yellowjacket” are loosely used for many types of Vespids that build paper nests and have black and yellow (or white) markings on the abdomen.
Like honey bees, Vespid wasps live in “societies of heavily armed females,” as Tim Tiner and Doug Bennett describe them in their book “Wild City.” To understand how these societies are structured, we need to go back to last fall. Having mated and carrying a year’s supply of sperm, young queen wasps spend the winter hibernating alone in crevices. When spring arrives, each queen begins the process of starting a new colony by gathering wood fiber to masticate into a pulp, which dries into a paper-like nesting material. Depending on the species, the nest will be located in an underground cavity or aboveground attached to trees or buildings.
The queen starts the nest by constructing several hexagonal, egg-carton-like cells suspended from a short stalk and enveloped with a paper covering. She then proceeds to lay an egg in each cell. A week or so later, the eggs hatch and the busy queen must then feed the larvae small pieces of protein rich food such as bits of caterpillar or carrion. After about 12 days, the outer skin of the worm like larvae hardens into a tough casing. The developing wasp is now called a pupa and will undergo a radical change in form. Pupae do not eat.
After another 12 days, an adult wasp emerges from each of the pupal cases. All of these individuals are sterile females called workers. They immediately begin to work for the queen, enlarging the nest, gathering food and taking care of the new young. However, not all of their hard work is altruistic. In an amazing exchange of material called trophallaxis, the larvae secrete a sugar material relished by the workers. The queen, all the while, continues to lay eggs.
As most everyone knows, the workers are armed and dangerous, especially when they perceive a threat to the colony. Because these females are also sterile, they do not use their ovipositor as an egg-laying tube. Rather, it has been modified into a stinger, which is able to pierce the skin and inject a small amount of venom. Unlike Honey Bees, which have barbs on the stinger that cause it to break off when pulled out (thereby killing the bee), wasps lack these barbs and can therefore deliver multiple stings over the course of their lives. Wasps tend to be most aggressive in late summer, maybe because of the large number of offspring in the nest, which offers a great nutrient jackpot to predators like raccoons, skunks and bears.
As fall approaches, something unique happens. Sensing the shorter days, the queen begins to lay unfertilized eggs that will develop either into males (drones) or into new queens. These individuals will go on to mate, but only the newly fertilized females have the ability to overwinter. The rest of the colony dies including the hardworking queen with the first hard frosts of fall.
One of the most commonly-seen Vespid wasps is the Eastern Yellowjacket (Vespula malculifrons). It can be identified by the triangular, black “anchor-shaped” marking on the segment of the abdomen nearest the thorax. The triangle has a narrow black stem or neck, which extends to the upper edge of the abdomen. Yellowjackets usually nest in the ground, often in an abandoned animal burrow. As summer ends, there is a frantic search for food to feed the thousands of larvae still in the nest. Caterpillars are the larval food of preference but these wasps will also turn to dead insects and to human foods as a source of protein for the colony. Adults also need sugar in order to fuel the energy requirements of their own bodies. In addition to what they receive through trophallaxis, some of their favorite sources of sugar include flower nectar (especially goldenrod), ripe fruit and aphid honeydew, which is usually gleaned from tree leaves. However, as we know all too well, wasps are also attracted to the same sweet drinks as humans. Hot, dry summers provide the best breeding conditions for wasps, because this kind of weather also means high survival rates for the insects on which wasps feed. Under these conditions, yellowjacket colonies can expand rapidly. Some will have as many as 4,000 to 5,000 workers and a nest of 10,000 to 15,000 cells by summer’s end.

Eastern Yellowjacket eating aphid honeydew (Drew Monkman)

Eastern Yellowjacket eating aphid honeydew (Drew Monkman)

The Bald faced Hornet (Dolichovespula maculata) is another common Vespid. It is a little larger than a yellowjacket and has a mostly black body with yellowish white markings on the side and face. Hornets catch our attention because of their habit of building globular paper nests in trees. All summer long, colonies of these insects chew the fiber of trees and boards. Like yellowjackets, they turn the fiber into a saliva soaked pulp that dries into the fine, grey paper walls of the nests. The nest starts out small but grows in progressive layers over the course of the summer. A large colony can harbor up to 600 individual hornets by September. They are a species that needs to be treated with respect.
After the first few weeks of frost, it is safe to open an old hornet to see the intricate design and various levels of nesting tiers. There are usually some cells with dead larvae and pupae, as well. No wasps, including the new queens, ever overwinter in the nest.
Usually by late August, egg laying ceases in yellowjacket and hornet colonies and there are fewer larvae to feed. Consequently, the workers are no longer receiving sugar from the larvae in exchange for protein. They therefore start to abandon the nest to satisfy their own all-consuming sweet tooth. With a sugar fix in mind, wasps will sometimes descend upon family picnics, backyard barbecues and schoolyards full of juice-drinking children. These “bees”, as kids mistakenly call them, can be a real problem, especially around open garbage pails full of discarded juice containers.
Like all living creatures, wasps play an important ecological role. Because most Vespids prey on insects and other arthropods, they help to control the numbers of many pest species. It takes a lot of bugs to feed a hungry brood. Yellowjackets also scavenge dead insects to feed their offspring – an important ecological service, too. Some species of wasps are also important pollinators. Fig trees, for example, depend entirely on wasps for pollination. In fact, the relationship between fig trees and fig wasps is one of the best examples of co-evolution in the nature. The fig shaped the wasp and the wasp shaped the fig. Wasps are just one more example of how the natural world never ceases to amaze.

Bald-faced Hornet - Wikimedia

Bald-faced Hornet – Wikimedia

Bald-faced Hornet nest (Ian MacDougall)

Bald-faced Hornet nest (Ian MacDougall)

 

Jun 192014
 

For anyone with an interest in wildflowers, June is synonymous with orchids. At least a dozen species of this fascinating plant family bloom this month in the Kawarthas, and the spectacle is not to be missed. In addition to their exquisite colours and designs, orchids are a wonderful testament to the power and wonder of evolution.
The Kawarthas has long enjoyed a special status among orchid lovers. The first book on Ontario’s orchids was researched and written here by a Peterborough resident, Frank Morris, in 1929. Some of the most interesting passages are his vivid descriptions of orchid searching trips to the Cavan Swamp and Stony Lake. Unfortunately, one becomes immediately aware that orchids were much more plentiful at that time. Because of habitat loss, indiscriminate picking and digging up for transplanting into gardens, most orchid species have declined greatly in number. In fact, I recall that well-known naturalist Doug Sadler once told me that in the 1950s people used to sell bouquets of Showy Lady’s slippers at the Peterborough Farmers’ Market!

Showy Lady's-slipper - Drew Monkman

Showy Lady’s-slipper – Drew Monkman

Peterborough County is home to about 36 orchid species including one, Helleborine, which is an alien species from Eurasia. Of the 36, 14 are considered rare or their presence is based on very old records. Species belonging to the genus Cypripedium, commonly known as lady’s slippers, are the most renowned of our orchids. The Kawarthas boast four species. Probably the best-known member of this genus is the Pink Lady’s slipper, also known as the Moccasin flower. It is usually found in dry, upland sites, quite often in association with pines. Petroglyphs Provincial Park and the north shore of Stony Lake provide good habitat for this species. The largest of our native orchids is the Showy Lady’s slipper which measures up to 80 cm in height and occurs in open to semi shaded wetland edges. This species requires 10 years of growth from germination to the time it flowers. Dry to moist calcium rich sites are the preferred habitat of the Yellow Lady’s slipper, possibly our most common member of the genus. This species is widespread in the Warsaw area. The Kawarthas also has good numbers of Ram’s head Lady’s slipper. They prefer cold, undisturbed wetland edges and are often found in association with White Cedars.
One reason I love orchids is that they have so much to tell us about evolution. They show amazing adaptations – or contrivances, as Charles Darwin described them – to attracting and exploiting their insect pollinators. In his book “Fertilization of Orchids”, Darwin explained in detail the complex relationships between these flowers and their pollinators and how this led to the co-evolution of both. He realized that as the insects changed, so did the orchids that were dependent upon them. And vice-versa. Darwin’s work provided the first detailed demonstration of the power of natural selection. Co-evolution between orchids and insects has led to an incredible amount of diversity. In fact, with close to 30,000 different species, orchids represent the world’s largest family of plants. They are also a very old family. The first orchids are believed to have appeared some 80 million years ago. This means that they may have co-existed with dinosaurs! Despite the huge number of species, most orchids tend to be uncommon and almost never dominate a given landscape. Paradoxically, they produce seeds in astronomical quantity well over a million in some species.
The Pink Lady’s-slipper, one of the more common local species, provides a great example of the complicated dance between orchid and pollinator. Its sweet odour and enticing pink pouch – a modified petal – attract bumblebees. On the hunt for nectar and pollen, these large, hairy insects pry their way into the large, slipper-like pouch through the incurved slit down the front. Once inside, the slit closes and traps the hapless bee. Exiting by where it entered therefore becomes impossible. But, it’s not all bad news. The upper part of the pouch is lined with sticky hairs coated in nectar, and there are translucent areas where light shines through. Attracted by the light and sugar reward, the bee climbs upwards to gather nectar and to make its escape. The pouch constricts, however, below two small exits to the outside. In order to regain its freedom, the bee must crawl under a large flattened structure. As it does so, the insect’s back rubs up against the stigma, the female part of the flower. Any pollen sticking to its body – presumably from another orchid it visited earlier – is scraped off. Bingo! The orchid is pollinated. But one last bit of trickery still remains. As the bee finally makes its way out of one of the strategically-located exit holes, it inadvertently rubs up against a sticky mass of pollen grains, which adheres to its back and sides. If it enters yet another Pink Lady’s-slipper, the bee will follow the same path and unwittingly leave behind pollen once again. In this manner, cross pollination between plants is assured.
Despite this elaborate pollination mechanism, Pink Lady’s slippers seem to spread mostly through their rhizomes. Rhizomes are underground, creeping stems that are capable of forming new plants. This explains why, unlike most other native orchids, Pink Lady’s-slippers are sometimes found in large masses.

Pink Lady's-slipper - Thomas Barnes

Pink Lady’s-slipper – Thomas Barnes

Three other species are of considerable interest this month, both because of the unique design of their flowers and the special habitats in which they grow. They are the Arethusa (Dragon’s mouth), Calopogon (Grass pink) and Rose Pogonia (Snake mouth). All three are pink in colour and grow in the acid soil of bogs and wet meadows. All can be found in Kawartha Highlands Provincial Park. Pollination for these species, too, depends on some very clever adaptations. In the case of Calopogon, downright deception comes into play. Bees are immediately attracted to the top petal of the flower because of a mass of stamen like objects, which appear to be loaded with pollen. However, upon landing on these hairs, the insect quickly realizes there is no pollen to be found. But, before it can fly away, the bee’s weight causes the petal to collapse downward. The hapless bee ends up on its back, pinned against a trough like appendage that contains the true sexual parts of the flower. The bee’s hairy back may pick up sticky pollen located here or transfer pollen from a previous visit to another Calopogon to the stigma, thereby assuring pollination. Evolution rarely takes the easy route to solving the challenges of reproduction!
Orchids, like all plants, follow a definite blooming schedule. Most of the lady’s slippers bloom in late May through mid June. Showy lady’s slipper, however, along with Arethusa, Calopogon and Rose Pogonia, usually bloom in late June. Rose Pogonia can sometimes still be found in flower as late as mid July. Later in the summer, watch for Spotted Coral root (July), Dwarf Rattlesnake plantain (late July and August) and Nodding ladies’ tresses (late August and September). Once again, Petroglyphs Provincial Park is a good place to try for all three of these summer blooming species. Ladies’-tresses also grow in damp areas along the edge of the Trans-Canada Trail, just east of Highway 7.
It’s important to resist the temptation to dig orchids up and transplant them into your garden. Not only does this put the species further at risk, but it is rarely successful. Orchids depend on a special relationship with fungi, which provide the plants with minerals and other nutrients that they cannot attain by themselves. Without the presence of the right fungi in the soil, most orchids will not survive.

Calopogon - Drew Monkman

Calopogon – Drew Monkman

Apr 102014
 
American Woodcock - Karl Egressy

American Woodcock – Karl Egressy

With monikers such as pop-eyed shot dodger, bogsucker, sky dancer and timberdoodle, the American Woodcock may have the most evocative nicknames of any bird. This game specie’s  real claim to fame, however, is its spring courtship flight, in which males fly high overhead on twittering wings before returning sharply to the ground to resume their unique “peenting” calls. The American conservationist Aldo Leopold famously wrote that such dawn and dusk “sky dances” are a living “refutation of the theory that the utility of a game bird is to serve as a target, or to pose gracefully on a slice of toast.” Although woodcock can be found all over the Kawarthas, many people spend their whole life never knowing such a bird exists. What a shame this is, because the sight and sound of displaying woodcock is a true spectacle of spring.

A unique bird

Woodcock arrive back in late March from wintering grounds in the southeastern states. Their arrival more or less coincides with the thawing of the soil, which frees up their favourite food – earthworms. Migrating birds will sometimes show up in suburban backyards and create quite a stir as people try to figure out the identity of the rather ridiculous-looking visitor. The woodcock is indeed quite comical, with its bizarre anatomy and even stranger behaviours. It is similar in size and shape to a starling, but with a mottled colouration of blacks, browns, tans and whites, which provide near-perfect camouflage against the dead leaves, and twigs of the forest floor. Evolution has also provided the woodcock with very large eyes, located high and well back on the head. The size and placement allows the bird to see in front, behind and even above, affording a view of approaching predators such as domestic cats, hawks, owls and coyotes. This adaptation is extremely important because woodcocks spend a lot of time with their head down and their bill deep in the mud. The males also draw a lot of attention to themselves during their courtship displays.

Like many shorebirds, the woodcock also has a long bill – as long as your middle finger – with which it probes deeply into soil for earthworms. The sensitive, flexible bill tip can feel a worm in its underground burrow and then open to grab it. This feat is nearly impossible for other birds.

The woodcock’s walking style is also quite different from other birds. It tends to amble slowly along, all the while rocking its body back and forth. Its head, however, remains motionless. This strange gait is accompanied by a kind of foot-stomping, which is thought to cause worms to move around in the soil, thereby making them more easily detectable

Sky Dance

American Woodcock face - Wikimedia

American Woodcock face – Wikimedia

The woodcock behavioural claim-to-fame, however, is its amazing courtship flight or “sky dance.” From late March until early June, the male performs one of the most fascinating courtship spectacles in nature, in which he goes to extraordinary lengths to show his fitness and virility to females. The sky dance is performed over openings known as singing grounds. Beginning in the near-dark evening twilight, the male starts to “peent.” The sound is reminiscent of a buzzy, nasal toy horn. As darkness falls, the peents become more numerous until, all of a sudden, the bird bursts into the air and flies upwards in wide circles.

Because the woodcock’s three outer wing feathers are  stiff, narrow and spread apart during flight, the air rushing through causes them to vibrate, producing a high, mechanical, twittering sound. After reaching a height of about 100 metres (300 feet), the twittering becomes intermittent, and the bird soon begins a zigzag descent. A third sound is then produced as the woodcock starts singing liquid, kissing notes – just in case the flight itself was not enough to impress the hard-to-please female! The kissing notes grow louder and louder as he approaches the ground, but then cease completely for the final portion of the descent. The bird usually lands almost at the same spot from whence he took off. He then walks stiff-legged in the direction of the nearby female, wings stretched vertically. Soon after, he begins peenting once again. A few minutes later, the poor bird—probably close to exhaustion — launches into yet another flight. Woodcock will display for up to an hour at dusk and dawn and even through the night if there is a full moon.  Click here for a YouTube video of the sky dance.

The males will mate with any female impressed with his display. However, there is a catch. He provides no help with nest-building, incubation of the eggs or with brood rearing, but simply turns his attention to attracting other females. All of the woodcock’s various sounds can be heard by visiting allaboutbirds.org. To see and hear a great video of the aerial display, go to YouTube and search for “American Woodcock Air Dance”.

Seeing woodcock  

American Woodcock are birds of habitats that are in transition, such as abandoned farmlands reverting to forest. They also frequent second-growth forest edges and low, damp, brushy fields of alder, poplar, cedar, etc. One place to see them is from the parking lot at the Trent Wildlife Sanctuary on University Road. If the birds are not displaying here, cross the road to the canal side and walk straight ahead to the brushy field along the Morton Family Trail, being careful not to turn left up the hill. Listen carefully for the peenting sound. Because the darkening sky makes it difficult to actually see the woodcock in flight, try to face west. In this way, the bird will stand out against the lighter, western sky. After it takes off, you can move a little closer to the take-off point. By remaining quiet and staying low, it is often possible to end up as close as two metres to the bird when it lands.

Woodcock also garner attention in the fall, because they are one of the few shorebirds that is hunted for sport. They often flush right from under the hunter’s feet and fly at “jet-propelled speeds on a corkscrew trajectory” as local outdoor writer Jack Davis once wrote. Another author described their flight as ‘the shortest distance between two points which includes two zigs, a zag and at least one drastic change in altitude.”

So, what is the value of this odd bird? For a birder, the woodcock is simply thrilling to watch and a great species to add to the day list; for the more scientifically-inclined, the bird’s many adaptations exemplify the power and wonder of evolution; for  people who are simply interested in natural history, the woodcock’s amazing behaviour prompts fascination and sheer aesthetic enjoyment; and for hunters, the bird represents not only a delicious meal but also the pleasure of being out on a crisp autumn day and shooting such a challenging target. This multiplicity of values is true about nature as a whole. As Yale scholar and environmentalist Stephen Kellert writes, when viewed from any single value, the woodcock – and species in general – can be easily marginalized and rendered irrelevant. Yet when seen in a broader spectrum of relationships…this bird becomes another portal for deepening our sense of selfhood and membership in a broader community, enriching both our personal and collective lives.

Spring Wildlife Walks

            Each Sunday morning in April and May, the Peterborough Field Naturalists are holding a spring wildlife walk. Meet at 8 a.m. at the parking lot of the Peterborough Zoo. The outings last for about three hours and are lead by a variety of local naturalists. They will be taking participants to different locations in the Peterborough area. Although the focus is on birds, wildflowers, trees and other aspects of spring in the natural world will also be enjoyed. Everyone is welcome. For additional information, contact Martin Parker at 705 – 745 – 4750 or Paul Elliott at 705-740-0501.

 

Mar 132014
 

 

 

Neil deGrasse Tyson

Neil deGrasse Tyson

I hope you had a chance to watch the first episode of the wonderful new science documentary series Cosmos: A Spacetime Odyssey that aired Sunday night. It is presented by the famed astrophysicist Neil deGrasse Tyson and is a follow-up to the 1980 television series Cosmos: A Personal Voyage, which was hosted by Carl Sagan. Dr. Tyson reminded us how we as human beings have come to possess such incredible knowledge about the nature of the Universe and the story of life itself. “This adventure is made possible by generations of searchers strictly adhering to a simple set of rules. Test ideas by experiment and observation. Build on those ideas that pass the test. Reject the ones that fail. Follow the evidence wherever it leads and question everything. Accept those terms and the Cosmos is yours.” In my recent columns on evolution, that is what I have been trying to say: we have to respect science. Unless something better can be invented, it is our best way of knowing about the nature of reality.

Why I care

The natural world is under siege. Humans have brought about what scientists are calling the sixth great extinction. Up to 50 percent of all living species are in danger of disappearing by the end of the century – primarily because of climate change. Anti-science attitudes and religious fundamentalism are part of the reason why addressing this crisis is so difficult.

Carl Sagan

Carl Sagan

It has always concerned me that creationists and other religious fundamentalists have rarely made protecting living Nature an important part of their teaching. As E.O. Wilson asks in his 2006 book “The Creation”, “do they believe that human-centered ethics and preparation for the afterlife are the only things that matter?… For those who believe this form of Christianity, the fate of ten million other life forms indeed does not matter.” What is even more disturbing, creationism now seems to have coupled itself with a rejection of climate science. The very idea of science as a way of knowing about the world is being challenged.

In his column of March 1, Jim Mason, a retired physicist, biblical creationist and speaker for Creation Ministries International, presented 12 questions “requiring answers with scientifically supported data.” I will address these questions. First, however, I would like to remind readers of the nature of this so-called “debate”.

• Creationism is the product of faith: Creationism proceeds from the account of the world as told in Genesis and expects the world to conform to that account. Consequently, the conclusion is already held to be true. Instead of citing evidence for why creationism is factual – and presenting this evidence in peer-reviewed scientific journals – creationists try to show why evolution isn’t. Science, on the other hand, doesn’t really “believe” anything in the way that religious faith does. Science looks at the totality of evidence and determines what the current most likely answer is that is consistent with that evidence. At some point, scientists pass a threshold where it would be (to paraphrase Stephen Gould) “perverse not to agree with the scientific evidence”. Like the theory of gravity and the germ theory of disease, the theory of evolution passed this threshold of evidence long ago. The objections raised against the theory of evolution do not come from scientists.

• How creationists argue: Because creationism can’t really offer competing scientific evidence, they often present what are known as ‘arguments from ignorance’, which are questions that science has not yet completely answered. The implication is that because something is not fully understood (i.e., there are gaps in our knowledge) God must be responsible for that phenomenon. We call these “God of the gaps” arguments. There are also ‘arguments from incredulity’, which imply that because something is difficult to understand or seemingly amazing – the evolution of the human eye, for example – only a supernatural force could have done it.

• The real problem: The problem creationists have with evolution is not that it challenges belief in God, because it doesn’t. Their problem is that evolution – like geology and astronomy – challenges the accuracy and authority of a literal interpretation of the Bible -especially the book of Genesis as an exact historical account. Yet, many religious people accept the theory of evolution and still maintain devoted religious lives.

 

Tiktaalik

Tiktaalik

The questions

The questions that Mason has posed all come from the Creation Ministries International website. You can find them at creation.com/question-evolution. If you wish to read a more detailed rebuttal than what I am providing, please go to rationalwiki.org/wiki/Question_Evolution Remember, however, that the answers to some of these questions involve complicated science and do not lend themselves to short answers. It is why scientists spend many years at university!

1. How did life originate? This question is irrelevant, because evolution does not claim to explain the origin of life. Abiogenesis, the natural process by which life arose from non-living matter, is not part of the theory of evolution. Still, science is getting closer and closer to answering this ‘God of the gaps” question.

2. How did DNA originate? DNA most likely evolved gradually from a simpler replicator; RNA is a probable candidate. What we have trouble grasping is the incredibly long period of time evolution has had to work with. Life has been evolving for 3.5 billion years. It would take you about 110 years to count to 3.5 billion, even if you counted day and night!

3. How could mutations create the huge volumes of information in the DNA of living things? There are many processes that increase genetic information. The most basic is that of gene duplication. Another mechanism is viral insertions – literally inserting new genetic material into a genome.

Sinosauropteryx prima feathered dinosaur plate Early Cretaceous Yixian Formation Liaoning China

Sinosauropteryx prima feathered dinosaur plate Early Cretaceous Yixian Formation Liaoning China

4. How did new biochemical pathways originate? This is basically an argument that biological structures and processes are too complex for a natural explanation to account for them. With time and proper mutations, completely new pathways do, in fact, originate.

5. How does evolution know living things weren’t designed? The claim that living things bear the hallmarks of design is, at best, a mere assertion. Complexity does not imply design; in fact, simplicity is a design goal in most designs. Historically, supernatural design has been attributed to lots of complicated things that we now know occur naturally, such as lightning, rainbows, and infectious diseases.

6. How did multi-cellular life originate? It was beneficial for single-celled organisms to work together. For instance, mitochondria, the “power sources” of cells, were once separate organisms. In a recent study by William Ratcliff and his colleagues at the University of Minnesota, single-celled yeast took less than 60 days to evolve into many-celled clusters that behaved as individuals.

7. How did sex originate? Sexual reproduction allows for evolution to occur at a much faster pace than asexual reproduction. Organisms that exchanged DNA were thus able to evolve out of situations that might have killed their asexual counterparts.

8. Why are countless millions of transitional fossils missing? They aren’t. Every fossil ever found is a link between older and newer forms. One of the most interesting is the Tiktaalik, a transitional fossil between fishes and amphibians. It is basically a fish with legs. Its “fins” have basic wrist bones and simple rays reminiscent of fingers. There are also transitional fossils between reptiles and birds, such as the feathered dinosaurs being dug up in China.

9. How did ‘living fossils’ remain unchanged? A living fossil – not a scientific term – is a species or group that has an extensive fossil record but also retains known living specimens, which show a similar appearance. It is quite possible, for example, that while living fossils have a similar exterior appearance, their internal biochemistry has changed dramatically.

10. How did blind chemistry create mind/intelligence, meaning, altruism and morality? Organisms develop from egg to full organism all the time through “blind” chemistry. Is that a problem? Also, evolution can be true regardless of the perceived moral implications. That being said, morality is actually part and parcel of evolution. It is linked to what happens when organisms live socially. Since humans are social animals and they benefit from interactions with others, natural selection – the mechanism by which evolution operates – has favoured behavior that allows us to get along better with others.

11. Where are the scientific breakthroughs due to evolution? Evolutionary concepts are applied to everything from understanding how diseases and pests evolve resistance to the drugs and pesticides to providing alternate explanations for physical and many cultural differences between different peoples. This allows us to debunk judgemental explanations that have led to conflict in the past.

12. Why is a fundamentally religious idea taught in science classes? Evolution merely describes part of nature. The fact that that part of nature is important to many people and is pursued with zeal does not make evolution a religion. If this was the case, even stamp collecting could be called a religion. Religions explain ultimate reality and the origin of life. Evolution does neither.    

                Even in 2014, denying the science of evolution – and climate change – represents a real danger to science literacy, science appreciation and to finding solutions to the environmental crisis. Let’s hope that the remaking of Carl Sagan’s Cosmos documentary will help to usher in a new respect for science and inspire us all in how amazing reality actually is. Don’t miss it next Sunday night!     

 

Feb 202014
 

A basic understanding of the theory of evolution provides both  emotional and intellectual satisfaction to the experience of observing nature. It adds a whole new level of appreciation to the cardinal you’re watching at your feeder or to the orchid that’s blooming on your windowsill. Evolution allows us to ask “why questions” such as “why are male cardinals so brightly coloured?” and to expect a reasonable answer. And, as we all know, the answer to a why question is deeply satisfying.  

 Northern Cardinal - by Ruthanne-Sobiera


Northern Cardinal – by Ruthanne-Sobiera

At its simplest, the theory of evolution – theory meaning a unifying principle that explains a body of facts – describes how modern organisms have “descended with modifications” from ancient ancestors as a result of genetic inheritance. It’s central idea is that all life on Earth shares a common ancestor, just as you and your cousins share a common grandfather and grandmother.  It therefore means that we’re all distant cousins: humans and cardinals, Monarch butterflies and orchids.

            In a nutshell, evolution can be understood like this: All creatures struggle to survive and reproduce but many fail. Any creatures born with a new, helpful trait are the most likely to live long enough to reproduce. Parents pass on the useful trait  to their young. Over time, the population with the new trait(s) becomes so different that it has “evolved” into a new species  – in other words, a group of organisms that can only reproduce with individuals of this same, new group. For example, cardinals can only breed with cardinals and robins with robins.  

            Now, let’s take a slightly more detailed look. Charles Darwin, a 19th century English naturalist and the father of the theory of evolution, realized that plants and animals have far more offspring  than they need in order to replace themselves. He reasoned that if all the offspring were to survive, the planet would quickly be over-run. He therefore wondered why some of the young endure – at least long enough to reproduce – while others don’t. He did, of course, recognize that life is a struggle and finding food, a mate, shelter and other essentials is rarely easy. Darwin had the genius, however, to notice that not all offspring are exactly the same. In every generation, there are slight differences in size, colour, behaviour and other features. He therefore concluded that some of these traits (e.g., a larger, stronger beak) would give the individual an advantage over its siblings and therefore improve its chances of surviving and reproducing. He called this “natural selection”. Nature is, in a sense, choosing or “selecting” those individuals that will survive.

            Imagine a species of beetles. Because there is variation in traits, you could have some individuals that are green and others that are brown. We see this phenomenon in Gray Squirrels, in which some are black and others grey. Imagine a new predator arrives on the scene and is able to more easily spot and eat the green beetles. This means that fewer green beetles will survive to reproduce than brown beetles. The surviving brown beetles will have brown babies because colour in this example is a genetic trait. The advantageous trait of being brown will become more common in the population and eventually all of the beetles will be brown.

Viceroy (above) and Monarch

Viceroy (above) and Monarch

You have a  great example of natural selection observable right in your own garden with  the Viceroy butterfly. Through natural selection, Viceroys – a non-poisonous species – have evolved to almost perfectly mimic the poisonous Monarch butterfly in appearance.  Because birds learn that certain wing patterns and colours are unpalatable, they not only avoid attacking Monarchs but also avoid the near-identical Viceroys. This, of course, provides Viceroys with protection and has helped countless generations to survive and pass on their genes.

            Natural selection of a different kind can be seen in the appearance and behaviour of the male birds at your feeder. In this case, the selection pressure is coming from the female. Known as sexual selection, it determines which males will get to mate. Remember, males compete for access to females and not all males win the jackpot. So, who are the lucky guys? Well, depending on the species, the fastidious female may decide that she especially likes males with  brightest feathers or the most vigorous song. In her estimation, these traits make the suitor genetically superior and more “fit” to be a father. Males with these traits will therefore get to mate more often and the traits will be passed down to the offspring. It is sexual selection – the end result of the decisions of countless generations of females – that explains why male cardinals are so ridiculously red and why they pour their souls out in lusty song. Bright coloration and loud song from exposed perches have a downside, however, in that it means male cardinals are more easily detected by predators. Nature is always a series of trade-offs.

            This leads to two important thing to keep in mind about natural selection. This process  does not produce perfection. No population or organism is ever perfectly adapted.  A predator is never fast enough to catch its prey every time it is hungry, nor is it perfectly protected from enemies.  Natural selection is not random, either. Randomness only apples to gene mutations. As a result of natural selection, mutations that aid survival and reproduction are much more likely to be “selected” than mutations that don’t. This is the opposite of random.

Darwin's Orchid with long spike (spur)

Darwin’s Orchid with long spike (spur)

Although it was not understood in Darwin’s time, new traits occur because of changes in DNA, a long, chain-like molecule inside every cell of every living creature. A section of DNA forms a gene. Plants and animals can have hundreds or thousands of genes. There are genes for everything from eye colour to whether hair is straight or curly. Together, the genes act like a “recipe” for growing a living thing. However, when a cell divides and makes a copy of its DNA, the copy is not always perfect. The small difference between the original and the copy is called a mutation.  The mutation can slightly change the recipe. Mutations can have a big effect, small effect or no effect.

Not all selection is natural. The term “artificial selection” is used when humans – usually farmers and breeders – do the selecting and allow only the plants and animals with the most desirable characteristics to reproduce. This has led to the evolution of everything from different breeds of dogs to different vegetables. Just by starting with wild mustard, breeders have been able to cultivate broccoli, cabbage, cauliflower, kale and kohirabi. They are all the same plant species. As for dogs, they are all direct descendents of the Gray Wolf, Canis lupus and therefore all domesticated wolves. The 150-plus dog breeds we see today are the result of  purposeful interbreeding of dogs over the last couple of centuries.   

            New species resulting from evolution are usually just updates, not radical redesigns. For example, the same basic body plan (e.g., four legs) usually remains. A good example is the similarity in the skeletons of humans, horses and dogs. Some species are so well adapted to their habitat and lifestyle, that they have hardly changed since the time of the dinosaurs (e.g., crocodiles, dragonflies).

Morgan's Sphinx moth

Morgan’s Sphinx moth

 

 

The term co-evolution is used to describe cases where two (or more) species affect each other’s evolution. For example, an evolutionary change in the features of a flower might affect the features of a pollinator that visits that flower, which in turn might affect the evolution of the flower… and so on. For example, you would not  have the amazing shapes, markings and colours of your orchid house plants if it weren’t for the insects that pollinate them. Compelling evidence for co-evolution can be seen in Darwin’s Orchid, Angraecum sesquipedale. This orchid has an extremely long , hollow spike – so long that only an insect with a 12 inch proboscis (tubular mouthpart) can reach the nectar inside. Darwin actually predicted that there had to be a species of moth out there with such a proboscis in order for the orchid to be pollinated. Well, he was right. In 1903, twenty years after Darwin’s death, Morgan’s sphinx moth was discovered. The moth has a foot-long proboscis that can reach down into the flower to retrieve the precious nectar. In the process, the moth rubs its head against the pollen-producing organ of the plant and transfers the pollen to the next flower it drinks nectar from .  

           

To learn more about evolution, I would recommend visiting “Understanding Evolution” at http://evolution.berkeley.edu/ and watching the PBS series on evolution at  http://www.pbs.org/wgbh/evolution/. It is also available on YouTube.   

 

 

Feb 132014
 

 

Cy Monkman -father

Cy Monkman -father

Gordon Monkman - grandfather

Gordon Monkman – grandfather

Edwin Monkman - my great-grandfather

Edwin Monkman – my great-grandfather

 Robert Monkman - my great-great-grandfather

Robert Monkman – my great-great-grandfather

 William Monkman - my great-great-great-grandfather  Grandfather)

William Monkman – my great-great-great-grandfather Grandfather)

model of Homo erectus - my 50,000-greats-grandfather

model of Homo erectus – my 50,000-greats-grandfather

8. 7 million year old  Sahelanthropus tchadensis  - similar to my 250,000-greats-grandfather

8. 7 million year old Sahelanthropus tchadensis – similar to my 250,000-greats-grandfather

modern Lemur - possibly similar to my 45 million-greats-grandfather

modern Lemur – possibly similar to my 45 million-greats-grandfather

Silvanerpeton - an early reptile - similar to my 170-million-greats-grandfather

Silvanerpeton – an early reptile – similar to my 170-million-greats-grandfather

Reconstruction of prehistoric fish Panderichthys - my 185-million-greats-grandfather

Reconstruction of prehistoric fish Panderichthys – my 185-million-greats-grandfather

            Genealogy  has never been more popular. It’s wonderful to be able to trace our roots back in time and to see how the choices and life experiences of our ancestors have impacted our own lives. Both of my  parents have done a great deal of research on their respective sides of the family  and organized  the information and photographs in book form for the rest of the family to enjoy. My father has been able to trace the Monkman lineage back seven  generations to the 1700s in Yorkshire, England.

Today I’d like you to join me as I continue my father’s work, only this time going back an additional 185 million generations! The science involved in this ambitious undertaking comes courtesy of  Charles Darwin, the father of the theory of evolution and whose 205th birthday was yesterday. The other tool we’ll be using is a thought experiment described by Richard Dawkins in his 2011 book, “The Magic of Reality”. In this beautifully illustrated volume for younger readers, Dawkins separates “too-little-known facts from too-frequently-believed fictions” about the Universe and nature. He writes: “The magic of reality is – quite simply -wonderful. Wonderful and real. Wonderful because it’s real.”

To do this experiment, I’m going to start with a photograph of myself. Next, I’ll place a picture of my father, Cy, on top. I’ll do the same with pictures of my grandfather, Gordon, my great-grandfather, Edwin, my great-great-grandfather, Robert, and my great-great-great-grandfather, William. In my imagination, I’ll just keep piling on the pictures of great-grandfathers going further and further back in time. Remember, this is a thought experiment so not having actual photographs is not a problem.Now, stacking pictures of 185 million great-grandfathers – or great-grandmothers, had I preferred – is going to make for an awfully big pile. Even at three photographs per millimetre, the pile will soon get unwieldy. So, to make the stack more manageable, I’ll tip it on its side and pack the pictures along a single, winding bookshelf. It won’t be just any bookshelf, though. It will need to be 60 kilometres long! That’s approximately the distance between downtown Peterborough – let’s say the corner of George and Charlotte streets – to just east of Cobourg.

Come along as I walk along the bookshelf and pull out pictures as I go. We actually know what most of my (and yours) distant ancestors looked like by studying fossils. Fossils can  be dated, so we can say how long ago the fossilized animal lived. Keep in mind, however, that every picture in the line will look almost identical to the pictures before and after it. This is because change through evolution is very, very gradual.  Think of yourself. There was never a day when you went to bed as a baby and woke up as a toddler.

Our first stop is just 13 centimetres down the shelf at card 400. This represents about 10,000 years  ago when my 400-greats-grandfather lived. Looking at his picture, we wouldn’t notice any real difference from a modern person – once he’d had a shower and a shave, of course. Carrying on, let’s stop at 1.3 metres down the sidewalk (one big step) and pull out  a card from a hundred thousand years ago. Here we’d see a picture of my 4,000-greats-grandfather. Well, now, there would be a noticeable difference. His skull, for example, would appear a little bit thicker, especially under the eyebrows.

Walking another 15 metres or so will take us to 1.25 million years ago and a picture of my  50,000-greats-grandfather. Now, we would be looking at someone dissimilar enough to count as a different species, the one scientists call Homo erectusHomo erectus probably would not have been able to mate successfully (i.e., have viable off-spring) with a modern human, if the two were somehow to meet.  It’s important to remind ourselves once again that all of this change was extremely gradual. We are Homo sapiens and our 50,000-greats-grandfather was Homo erectus. But, there was never a Homo erectus who gave birth to a Homo sapiens baby.

Resuming our journey, we’ll stop next at six million years ago – just 80 metres down the bookshelf or half-way between Charlotte and King streets. This is where we’ll find a picture of my 250,000-greats-grandfather. He would be an ape and probably look a bit like a chimpanzee. However, he wouldn’t actually be a chimpanzee. He’d be the common ancestor that all humans share with modern chimpanzees. He would also be the 250,000-greats-grandfather of a chimp living today. One of his off-spring would have started the evolutionary branch that led to humans, while another would have begun the branch that led to modern chimpanzees.

Carrying on, we’ll catch our breath in front of the Holiday Inn and pick out the card showing my 1.5 million-greats-grandfather. Yes, that would be a tail we’re looking at! This is not surprising, however, since even modern humans still have a tail bone. The coccyx is the final segment of the vertebral column and is the remnant of what was once a human tail. Over time humans lost the need for a tail, and evolution through natural selection got rid of it.

Let’s see what the picture looks like if we stop at 63 million years ago, about 2.3 kilometres down the shelf at the corner of George and Lansdowne. Here we’ll see a photo of my seven million-greats-grandfather. He would look something like a lemur and be the ancestor of all modern lemurs, monkeys and apes, including us. Jumping in a car and driving south to Fraserville – passing an unbroken line of tightly packed photographs in the book shelf as we go – we’ll stop to look at the picture of my 45-million-greats-grandfather. He would also have been the ancestor of all modern mammals. Although family pride makes this hard to admit, this “Monkman” would have resembled a mouse-like shrew. By the way, he would also be a great-grandfather that you share with your cat, dog and hamster.

At card 170 million – 56 kilometres from the beginning and approaching Cobourg – is where we’ll find my 170-million-greats-grandfather. This relative of mine would have lived about 300 million years ago. Family pride would have to be completely re-evaluated at this juncture, since he would resemble a big lizard.  I could, however, take solace in the fact that he would have been the ancestor of all modern mammals, all modern reptiles, all modern birds and all of the dinosaurs. Another five kilometres east down the 401 will take us to the end of the shelf to just past Cobourg, where we’ll finally meet my 185-million-greats-grandfather. I would really have to brace myself  because we’d be looking at a picture of a fish. Terrestrial animals did not yet exist.

Now, we could, of course, go back in further in time but a lack of fossils makes it hard to know what these older great-grandparents would have looked like. We do know, however, that at about the 1100 kilometres mark – 3.5 billion years ago and somewhere close to the New Brunswick border – we would see a picture of the first life-form to exist on the planet. If our journey hasn’t impressed you enough yet, we could drive on to 4.5 billion years ago – somewhere around Moncton – and see a picture of our planet forming.  Bouncing in the waves out over the mid-Atlantic – at 12 billion years ago –  we could peer over the edge of the boat at pictures of the first stars dying in stellar explosions known as supernovae, in which  helium and hydrogen atoms were transformed into never-seen-before atoms such as carbon, oxygen, phosphorous and iron – the stuff of  life.  At  13 billion years ago and approaching Ireland,  we’d see hydrogen and helium atoms forming and  gathering together to make the first stars. Finally, at 13.7 billion years ago as we dock our boat at Galway, Ireland, we would see pictures of the Universe flaring forth, expanding and cooling in what we call the Big Bang. Before that? Let’s just say that modern physics is working on it. Now, is reality not amazing stuff! 

Side-bar:    Great Backyard Bird CountThe Great Backyard Bird Count (GBBC) begins tomorrow, February 14 and continues through Monday.  Simply count the birds you see over a 15 minute period – or longer if you wish – in one place, and report your results on line. Go to www.birdsource.org/gbbc/ for all the details. Be sure to explore last year’s Peterborough data by going to “Explore a Location”.