Burgess Shale Continues to Confound Life Is Simpler Today Than It Was Long Ago
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Environment Canada Environnement Canada Parks Service Service des pares 1990 Aussi disponible enfrangais NATIONAL yohoPAR K lllllll Burgess Shale Continues to Confound Life is simpler today than it was long ago. Today, creatures. Life today is less, not more, complicated than it there are only a few basic patterns for bodies to follow — was half a billion years ago. the mammal pattern, the bird pattern, the arthropod In a number of magazine articles and a best-selling pattern, and so forth. Long ago, things used to be much book, science writer Stephen Jay Gould has taken these more complicated. discoveries and explored their significance. In a radical In fact, this is the central truth underlying one of the departure from earlier theories, Gould says that Yoho most revolutionary discoveries in the National Park's unique fossil record history of palaeontology — and it all shows that today's animals, including started here in Yoho National Park! man, are the product of accident, Just up the hill from where our rather than the inevitable results of the new Travel Information Centre now stately march of organic evolution. stands, Dr. Charles Walcott, a scientist Is Gould right and Walcott wrong? with the Smithsonian Institute in the Are there new, even more startling United States, discovered the first of the revelations lying hidden in the thin Burgess Shale fossils in 1909. Dr. shale of the Stephen Formation? Walcott knew the find was special, Scientists, led by Dr. Desmond Collins but he couldn't imagine just how of the Royal Ontario Museum, con special. In Walcott's day, evolutionary tinue to search for the answers. theory presumed that today's living In a world where historians can't diversity had arisen from simple even agree on what happened yester beginnings through a long, slow day, it is unlikely that we will ever process of natural selection. Scientists have a complete picture of the life and assumed that a few simple animals environments of the" earth's adoles had gradually become more and more cence. The geological record is a book complex, and branched into more and of stone, with many pages smudged or more kinds of animals. missing. However, few of the pages Walcott, like others of his day, of time are as elegantly written, and as felt that the purpose of all this long, slow progression was to full of unique and startling revelations, as these thin produce mankind — the end product and highest achieve leaves of shale protected high in the Rocky Mountains of ment of evolution. He was excited with the discovery of a Yoho National Park. rich bed of fossils in 530-million-year-old rock, high on a shoulder of Mount Wapta. Walcott reasoned that these See Sharing the Story, Page 2 exquisitely preserved fossils were the simple, early ancestors of today's more complex creatures. In the last twenty years, however, scientists have HIGHLINE HIGHLIGHTS taken a second, more objective and detailed look at the Winter Challenge 2 Burgess Shale, and their discoveries have turned Superintendent's Message 3 Walcott's confident sense of man's ascendancy upside- Guide to Yoho 4 & 5 down. In fact, the animals of the Burgess Shale were more Wildlife Memorial 6 diverse and no less highly-specialised than today's living Park Information 8 2 Highline Sharing the Story The Burgess Shale is rigorously protected by the Canadian Stop at the overflow camping area at the beginning of the Yoho Parks Service. These fragile fossil deposits are of global scientific Valley Road. You will find a World Heritage Plaque celebrating the importance. Many Burgess Shale animals are known from one global importance of the Burgess Shale, and a colourful new exhibit single fossil specimen — if that specimen had been damaged or about the animals and discovery of the site. stolen by an unsuspecting amateur, the information it contained In the Travel Information Centre at the entrance to Field, an would have been lost forever. indoor exhibit contains some of the best of the Burgess fossils, and The park allows a very limited number of guided walks to the depictions of what the original animals looked like in their natural fossil beds each summer, but they are restricted to fifteen people or environment. If you ask the staff at the information desk, you can less, on a first-come, first-served basis. also get a colourful brochure. Several times each week, park naturalists give brief talks on the Many people haven't the time or energy for these steep hikes, Burgess Shale in front of this exhibit. Ask park staff for times and while others find that the hikes are not offered on the days when dates. they're in Yoho. To make the Burgess Shale story more accessible to The Friends of Yoho. a local society that works with the Parks our visitors, we have developed a variety of media closer to the road. Service, has a sales counter in the Travel Information Centre. Here This allows us to protect the fossil site while giving a much more you can buy Burgess Shale colouring posters for the kids, or get a complete picture of the Burgess Shale to many more people. copy of Wonderful Life. Stephen Jay Gould's new best-seller. Yoho Island — Earth National Park When astronauts took the first pictures of Earth from outer grizzly bears are hunted along the boundaries. Yoho's once remote space they forever changed the way in which we see the world and wilderness is now accessible by logging roads that penetrate to the our place on it. edge of our boundaries. From space, the boundaries of Yoho National Park are Like all of Canada's national parks, Yoho is becoming an invisible. This protected area, set aside in 1886 to be "preserved island besieged. Fortunately. Yoho is linked with three other great unimpaired" for all time, is just another part of the great Rocky parks (Kootenay, Banff, and Jasper) into a protected area so large Mountain ecosystem, with its glacier-fed rivers, forested valleys, that it is buffered against many of the effects of change. Other serrated peaks, and timberline meadows. national parks like Glacier, Mount Revelstokc, and Waterton Lakes If earlier generations had seen the globe as one green, are less lucky. Their wildlife populations and scenery have been interconnected life system, would they have been able to fool irreversibly changed by things over which park managers have no themselves with the idea that a national park can be protected merely control. by drawing a line around it and passing a few laws? Maybe they "When you touch one thing, you find it linked to everything would — after all, in 1990 many of us still have the same optimistic else in the universe," wrote John Muir, founder of the wilderness assumption. preservation movement. As national parks become increasingly Of course, it's true that Yoho National Park is one of the few threatened by events outside their boundaries, the truth of Muir's surviving places in North America whose environment looks almost statement becomes increasingly clear. the same today as it did a century ago. Wolves still howl on the If Yoho. and Canada's other national parks, are to survive Ottertail Flats, ancient forests stretch unbroken along the valley "unimpaired" for all time, it will only be because Canadians have slopes, and mountain goats live alone amid the rocks and wind of the taken to heart the truth that the Earth is one great, intricate, and high country. But that wind no longer smells the same as it used to. fragile ecosystem. It is all important, all connected... and all we Sweeping in from the southwest, Yoho's weather brings ozone have. pollution from distant cities and smoke haze from logging slash fires National parks are places that represent the richness of the throughout the province of British Columbia. Air pollution has world we share. Ultimately, each one of us will determine whether changed forests and damage watersheds in other parts of Canada — these parks, and this Earth, survive. As consumers, as voters, and in how impaired are Yoho's? the many individual choices we make in our day to day lives, we will Clear-cut logging has radically changed the valleys that border determine the future of this planet, and of the great national parks the park, and the changes affect animals that live in, and are that celebrate its diversity. supposed to be protected by, Yoho. Elk. moose, wolf, and black and A Yoho Winter Challenge Imagine fattening up all summer and fall, and then sleeping the the only large mammal adapted to withstand the harsh winter winter away. Oh, you might wake up occasionally to eat, but most of weather up high, where wind and cold limit the growth of vegetation the time your body survives on its fat reserves. to ground level and krumholz (stunted trees). The mountain goats That's the solution marmots, chipmunks, ground squirrels, blend in well with their white environment as they forage for alpine bats, and bears have found to cope with long, cold winters. While plants on windswept ridges. curled up in the safety of their dens, these animals make the best use Many animals that stay active in winter grow a thick coat of fur of their fat reserves through a lower temperature, a reduced or hair. A change in colur gives snowshoe hares, weasels, and heartbeat, and slower breathing. ptarmigans further protection. Their white fur or plumage Some animals avoid winter totally by migrating to warmer camouflages them in the snow to deceive predators.