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When Palaeontology and Philosophy Meet

By John Long

The Cambrian explosion of animal diversity, evident at the Burgess Shale fossil site, is fertile ground for philosophers to ponder.

This year at the Annual Society of Vertebrate Paleontology Conference in Calgary, Canada, delegates could opt for two special events. I enrolled in both. The first was a 1-day field trip to the world-famous Cambrian Burgess Shale fossil site, in the high mountains of British Columbia outside Banff. The second was a “Philosophy and Palaeontology” workshop held at The University of Calgary. While it might seem both are unrelated events, they actually meshed together beautifully, especially because the field trip came first with the workshop the day after.

The field trip was a long, hard day. We had to be on the bus by 4.30 am to get to the site and walk up the mountain in three groups so that only a limited number of people could each be at the Walcott Quarry to look for fossils. The Burgess Shale quarries have been a UNESCO World Heritage site since 1980 because of the incredible preservation and diversity of these Middle Cambrian fossils (505 million years old), which include a wide range of soft-bodied forms as well as typical hard-shelled creatures like trilobites and marine shells.

Nonetheless, the only way to get to the site is by walking the 21 km round trip to the site and back. The site is at an altitude of about 2350 metres, and the first leg of the hike is rather steep. When some of the group turned back at that stage, we all knew we were in for a hard hike to the site. Arriving at the site around 2pm, we found the quarry set among a backdrop of stunning mountains capped by glaciers with the Emerald Lake shimmering down below us.

The diversity of the Burgess Shale is extraordinary for any site this age, with at least 170 species recorded. Most of these belong to the joint-legged animals (Arthropoda comprise 59% of species known from Walcott Quarry), with sponges being the next most abundant group. Worms, molluscs, algae and other groups make up the rest. Many bizarre creatures, like Hallucigenia, whose affinities were at first unknown, characterise the assemblage.

For these reasons the site has generated much debate about the “Cambrian Explosion”, the point in time when animal life diversified rapidly. While some put this down to the fact that when soft-bodied animals are fossilised it greatly increases overall diversity, it is at the higher level of animal classification that we see Cambrian life really taking off. Most of the living phyla of animals had appeared by the middle Cambrian.

The nature of this diversity and how it relates to today’s living fauna is the perfect segue into philosophy. The Philosophy and Palaeontology workshop saw eminent philosophers present papers about the logic of palaeontology, with discussions developed by input from the attending palaeontologists. It was a perfect example of how science and humanities groups can work on common problems.

Much of the debate honed in on the nature of the big questions raised by the Burgess Shale fossils. The late Steven Jay Gould proposed in his book Wonderful Life that we higher vertebrates are only here because of a lucky throw of life’s dice. If the precursors to fishes like Pikaia and Metaspriggina were not around in the Cambrian, we would not likely have ever evolved.

There are many similar topics that philosophers like Dr Adrian Currie discuss and write papers about, from the theory of consciousness and palaeobiological laws to the luck required by palaeontologists working in the field. His blog Extinct (http://www.extinctblog.org/) provides other examples.

Of course, the really big contribution to philosophy by palaeontology and evolutionary theory combined is that we humans are just the product of billions of years of evolution, and therefore are solely responsible for our own destiny on this planet. Darwin dropped this big one in 1859, and the world has either been empowered or threatened by this thought ever since.


John Long is Strategic Professor in Palaeontology at Flinders University, and is current President of the Society of Vertebrate Paleontology.