Paleontologist scales the Rocky Mountains to uncover Earth’s very first animals

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Paleontologist scales the Rocky Mountains to uncover Earth’s very first animals

 

t’s 6:53 a.m. on Aug. 19, 2019. My body is primed to wake up — I beat my alarm clock by a couple of minutes. All is peace and quiet. The air inside the tent is cold, and it takes some conscious effort

 

to abandon my cozy sleeping bag. As I step out of my tent, I am taken aback by the breathtaking mountainous scenery. Enchanting! What new secrets will these mountains reveal today?

 

After a hearty breakfast and enough caffeine to keep us running, the field crew and I are finally ready to hit the road, except there is no road ahead of us here … only a two-kilometre hike uphill!

 

On our way out, the team is greeted by the squeaky call of a little pika, perhaps wishing us good luck. We reset the fence around our camp, charged with 5,000 volts of battery power to keep

 

curious bears out, and slowly make our ascent in the shadow of the towering rock walls.

 

The first rays of sunshine light up the rocky slopes as we arrive at our destination. There is not a single sign or sound of civilization around us, just the distant rumbling of Tokumm Creek. We are

 

standing on a small ledge at the foot of a huge cliff. Below us is a precipitous rocky slope with no end in sight. We tread carefully — the rocks are slippery.

 

Our team’s mission seems simple enough: to uncover the remains of animals fossilized within these rocks. Today, we might be lucky. We will see.

The Burgess Shale yields fossils half a billion years old

The rocks we are splitting are no ordinary stones: they belong to the famous Burgess Shale, a world-class paleontological deposit that was recognized as a UNESCO World Heritage site in 1980.

 

Famous for the exceptional preservation of soft-bodied animals dating back to the Cambrian period, the Burgess Shale records a critical period in life history often referred to as the Cambrian

 

explosion, which saw the global appearance and rapid evolution of animals in marine environments.

 

Take any animal today, on land or in the sea, and odds are good that there is a fossil from the Burgess Shale which can be connected to the base of its family tree. This story is featured in the new

 

documentary First Animals from The Nature of Things.

 

Since its discovery in 1909 by Secretary of the Smithsonian Charles Walcott in neighbouring Yoho National Park, the original Burgess Shale site has yielded more than 200 species of soft-bodied

 

animals. Normally, soft tissues decay after death, and animals that do not possess hard, mineralized structures like shells and bones will not leave any traces behind. The Burgess Shale, however,

 

experienced conditions that did not let the natural forces of destruction occur. The result is a fantastic snapshot of animal life that existed in tropical marine seas just over half a billion years ago.

A game-changing discovery

In 2012, a century after the first Burgess Shale rocks were first split, we made a game-changing discovery. While prospecting in northern Kootenay National Park, about 40 kilometres south of

 

Walcott’s original quarry, we uncovered spectacular new fossils. We named this new site “Marble Canyon” in reference to a narrow canyon carved by Tokumm Creek. Marble Canyon has since

 

yielded many new species and key new specimens, including those of Metaspriggina, a fish-like animal with an early precursor of the spinal cord, and a very distant cousin of you and me.

 

This year, we have expanded our fieldwork activities just a few kilometres north of Marble Canyon. Thanks to the expertise of my friend and colleague Robert (Bob) Gaines from Pomona College in

 

California, we targeted this new spot to conduct a small excavation, and in the few weeks since we started work here, our hopes have already been fulfilled.

 

Perhaps most strikingly, we have discovered dozens of examples of a strange carapace belonging to an animal that we had nicknamed “the spaceship” in previous years. (This type of carapace

 

turned out to be the head shield of a newly described predatory arthropod now known as Cambroraster falcatus.) What more are we going to find?

 

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