Wednesday 20 January 2010

CHUCKANUT FOSSIL TRACKWAYS

Chuckanut Drive is much younger than other parts of Washington. The fossils found there lived and died some 40-55 million years ago, very close to where they are now, but in a much warmer, swampy setting. The exposures of the Chuckanut Formation were once part of a vast river delta. Imagine, if you will, the bayou country of the Lower Mississippi. The siltstones, sandstones, mudstones and conglomerates of the Chuckanut Formation were laid down about 40-54 million years ago during the Eocene epoch, a time of luxuriant plant growth in the subtropical flood plain that covered much of the Pacific Northwest.

This ancient wetland provided ideal conditions to preserve the many trees, shrubs & plants that thrived here. Plants are important in the fossil record because they are more abundant and can give us a lot of information about climate, temperature, the water cycle and humidity of the region. The Chuckanut flora is made up predominantly of plants whose modern relatives live in tropical areas such as Mexico and Central America. If you are interesting in viewing a tropical paradise in your own backyard, look no further than the Chuckanut. Images and tag lines: Glyptostrobus, the Chinese swamp cypress, is perhaps the most common plant found here. Also abundant are fossilized remains of the North American bald cypress, Taxodium; Metasequoia (dawn redwood), Lygodium (climbing fern), large Sabal (palm) and leaves from a variety of broad leaf angiosperm plants such as (witch hazel), Laurus (laurel), Ficus (fig) and Platanus (sycamore), and several other forms.

While less abundant, evidence of the animals that called this ancient swamp home are also found here. Rare bird, reptile, and mammal tracks have been immortalized in the outcrops of the Chuckanut Formation including tracks of Diatryma, a massive flightless bird that reached up to 9 feet in height and made a living in the grasslands and swamps of the Eocene.

Tracks of a type of archaic mammal of the Orders Pantodonta or Dinocerata (blunt foot herbivores), footprints from a small shorebird, and tracks from an early equid or webbed bird track give evidence to the vertebrates that inhabited the swamps, lakes and river ways of the Pacific Northwest 50 million years ago.

WANNERIA DUNNAE

Wanneria dunnaeis an impressive trilobite from British Columbia's Eager Formation, and one of the more striking specimens found at the original research site of the lovely Lisa Bohach, a paleontologist now working out of Alberta.

The site has changed over the years, both physically and politically, but the one constant is the exquisite detail of the specimens. Both Wanneria dunnae and Ollenelus ricei are commonly found here. I had a eureka moment there a few years ago when ambling up the path to the main pit. The sun hit a wily would-be hiking track on a bit of shale at just the right angle. Closer inspection showed it to be a Tuzoia, one of the rare arthropods to come from the area.

Tuesday 19 January 2010

Tuesday 12 January 2010

MOONLIT PADDLE

CROCODILIAN UPSTARTS: THE CRUROTARSANS

Dinosaurs, long hailed as the rulers of the Triassic almost lost the title belt to a group of crocodilian upstarts, the crurotarsans. In a short lived battle for survival, geologically speaking, the two groups ran head-to-head for about thirty million years with the Crurotarsi butting their massive skulls and narrow snouts against their evolutionary opponent and ultimate successors, the dinosaurs.

The Crurotarsi or "cross-ankles" as they are affectionately known, are a group of archosaurs - formerly known as Pseudosuchians when paleontologist Paul Serono, the darling of National Geographic, renamed them for their node-based clade in 1991.

LIMESTONE AND SALT AIR: GORDES

Thursday 7 January 2010

CETACEA: HUMPBACK WHALE

Look at this lovely maternal bond between an adult Humpback whale female, Megaptera novaeangliae, and her young. Humpbacks are a species of baleen whale for whom I hold a special place in my heart. 

Baleens are whales who feed on plankton and other wee oceanic tasties that they consume through their baleens, a specialised filter of keratin that frames their mouths.

There are fifteen species of baleen whales. They inhabit all major oceans, in a wide band running from the Antarctic ice edge to 81°N latitude.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, whales are known as g̱wa̱'ya̱m. Both the California grey and the Humpback whale live on the coast. Only a small number of individuals in First Nation society had the right to harpoon a whale. It was generally only the Chief who was bestowed this great honour. Humpback whales like to feed close to shore and enter the local inlets. Around Vancouver Island and along the coast of British Columbia, this made them a welcome food source as the long days of winter passed into Spring.

Humpback whales are rorquals, members of the Balaenopteridae family that includes the blue, fin, Bryde's, sei and minke whales. The rorquals are believed to have diverged from the other families of the suborder Mysticeti during the middle Miocene. 

While cetaceans were historically thought to have descended from mesonychids— which would place them outside the order Artiodactyla— molecular evidence supports them as a clade of even-toed ungulates — our dear Artiodactyla. Baleen whales split from toothed whales, the Odontoceti, around 34 million years ago.

Tuesday 5 January 2010

Saturday 2 January 2010

Friday 1 January 2010

Thursday 31 December 2009

ALPINE ADVENTURE FOSSIL FIELD TRIP

Camping at about 7,500 ft, we were treated to all four seasons and some great collecting.

Over the course of the week we collected some beautiful ammonites, several of which are new species, and saw a buck with a sexy set of horns, flocks of Franciscans and a majestic lone wolf.

The area is home to active research by UBC paleontologist, Louise Longridge, and boasts abundant fossil marine specimens and a chance to see the Triassic-Jurassic boundary, a rare treat.

Wednesday 16 December 2009

HAIDA GWAII: ISLANDS OF FIRE

Located as they are in Canada’s most active earthquake zone, the Queen Charlotte Islands have had their share of shake-ups and scourings. Many of the Islands’ hillsides are scarred by slides. But the rock beneath speaks of an even more violent past.

Very few people know that the rock in the Queen Charlottes holds the key to a catastrophic event from eons ago. We’ve heard tales and seen images of the cataclysmic damage caused by meteriorites smashing into the Earth’s surface.

Until recently, it was a meteorite impact that was blamed for the worldwide Triassic/Jurassic Mass Extinction. This wholesale dying out of species occurred some 200 million years ago. New evidence challenges the meteorite theory. Experts now believe that tectonic forces may have caused hundreds of volcanoes around the world to erupt simultaneously. The subsequent showers of volcanic ash would have altered the composition of the atmosphere dramatically and plunged the world into near total darkness for years until it settled from the sky.

The picture painted of the sun flickering fitfully through inky clouds, paling against the torrents of glowing lava, while everywhere life is smothered, poisoned, or starved, rivals the most apocalyptic imaginings of Hollywood or religion. We know from worldwide evidence that the extinction was dramatic and affected upwards of 70% of the world’s biota.

Perhaps counterintuitively, for one might think of water as a refuge from fire, smoke, and lava, it was marine lifeforms that suffered the most. This is particularly well documented in the rocks of the Queen Charlottes, especially at Kennecott Point and Kunga Island.

Radiolarian microfossils, tiny, siliceous, single-celled microrganisms, tell the tale. In the Upper Triassic rocks, which predate the extinction by about 10 million years, radiolarians are preserved in hundreds of forms. Just above them, in the early Jurassic rock layers laid down about the time of the great die-offs, only a fraction of the previous number of forms are represented. The more recent Jurassic rock shows a rebound of radiolarian diversity, though of course, in different forms, a diversity which continues to flourish and expand in today’s oceans.

Monday 16 November 2009

Sunday 15 November 2009

Wednesday 11 November 2009

Sunday 1 November 2009

Tuesday 27 October 2009

Thursday 15 October 2009

LUSH BOUNTY

The Bowron Lake Circuit is home to a variety of plant life. Large sections of the forest floor are carpeted in the green and white of dogwood, a prolific ground cover we are lucky enough to see in full bloom. Moss, mushrooms and small wild flowers grown on every available surface.

Thursday 8 October 2009

Wednesday 7 October 2009

Saturday 3 October 2009

Friday 2 October 2009

Thursday 1 October 2009

Monday 28 September 2009

Friday 25 September 2009

RADIALARIANS: TIMEKEEPERS OF ANCIENT SEAS

Radiolarian microfossils, tiny, siliceous, single-celled organisms, make for excellent timekeepers. Think of them as the world's smallest clocks. These wee fellows have been living in the world’s oceans for about 600 million years. Because they occur in continuous and well-dated sequences of rock, they act like a yardstick, helping geologists accurately date rock from around the globe.

Wednesday 23 September 2009

Monday 21 September 2009

MEGAFAUNA: EXTINCT GIANTS

Megafauna were part of a cohort of "giant" animals, species of large animals, reptiles, birds and mammals that went extinct during the Pleistocene as our rellies, the homeo sapien sapiens, were spreading out of Africa and southern Asia to populate the globe. Our rise marked the demise of many of the Earth's most interesting beasts. The term, 'megafauna' refers only to those species larger than forty-five kilograms. Many smaller animals who lived along side these giants also disappeared during the Pleistocene, but it is the largest of the lot who get the title and our attention.

While the fossil record shows that most of the megafauna from North and South America, northern Eurasia and Australia went extinct during this time, it is not the case for all large beasts. Blue Whales, hippopotamus and elephants are notable exceptions, surviving into modern times.

Were we to blame? The court is still out, but most scientists agree that we played a small role at least. Larger scale hunting, climate change, and spreading disease have all been fingered as the culprit for the loss, but, like most ancient mysteries, evidence is mixed and the truth is complicated. My vote is that their ultimate demise is a combination of the three.

Wednesday 16 September 2009

FIRST LIGHT: HAIDA GWAII

The enormous difference between high and low tide in Haida Gwaii – up to twenty three vertical feet – means that twice a day, vast swathes of shellfish are unveiled, free for the taking.

An ancient Haida saying is still often heard today, “When the tide is out, the table is set.”

Archaeological evidence shows that by about five thousand years ago, gathering shellfish replaced hunting and fishing as their primary food source. The shellfish meat was skewered on sticks, smoked and stored for use in winter or for travel.

Tuesday 15 September 2009

Sunday 6 September 2009

Friday 4 September 2009

Tuesday 1 September 2009

Wednesday 26 August 2009