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The Burgess Shale

The Burgess Shale is a fascinating and rare cornucopia of strange life-forms that appeared soon after the Great Cambrian Explosion.

It’s what the scientists call a Lagerstätte. What happens is that a huge underwater mud slide buries an entire ecosystem. The mud excludes oxygen, and prevents any bugs from dining off the remains. So everything is preserved, totally squashed to be sure, often in the most exquisite detail.

The Burgess shale is a site in the Canadian Rockies where, in late Cambrian times around 500 million years ago, there just such mud slide. Some of the creatures uncovered show signs of being ancestors of modern animals. Others appear to be unknown to Science, and represent experiments in large-creature design which failed. Or perhaps not. As more people study these strange animals, more views emerge about what the Burgess Shale shows us.

This picture is of ‘Hallucigenia’, one of the Burgess Shale creatures. Its source is the Smithsonian Institute.

The Burgess Shale cornucopia was found by accident. And for many years it was hopelessly misinterpreted. However now that palaeontologists know where to look, similar creatures have been found worldwide. So even if some of the animals eventually failed to make the grade, they were successful enough in their time.

The story of the Burgess Shale seems to be changing fast, and I’ve not seen an up-to-date summary of what it teaches us.