Despite the fact that dinosaurs capture all our attention when talking about life in the past, very diverse animals have inhabited our planet for millions of years. Some were so strange that, next to them, the rarest dinosaur would seem as familiar as a house cat. It was in the Cambrian period, about 540 million years ago, when “the great Cambrian explosion” took place, and evolution gave rise to impossible animals : carriers of spines, tentacles, jaws, appendages, multiple eyes… animals so strange that they seem taken from the pages of a Lovecraft story.
Interestingly, in Lovecraft’s story “At the Mountains of Madness,” an expedition to Antarctica is recounted, where geologist William Dyer witnesses paleontological finds that challenge everything we know about life in the past and that show the existence of monstrous and, in our eyes, deformed intelligent creatures. In general, Lovecraft’s stories are full of monstrous creatures whose shape defies our sanity, with tentacles, jaws, impossible appendages, and curiously, who ruled the Earth millions of years ago.
They say that reality is stranger than fiction. And this is one of those cases. In this case, those Mountains of Madness are not in Antarctica: we are talking about Mount Stephen , in British Columbia, Canada. The famous Burgess Shale deposit was found there. Fossils collected there by geologist Charles Walcott over the years included arthropods, both trilobites and relatives of crustaceans, but the Burgess rocks revealed a myriad of animal forms.
From 1962 onwards, a new era began in the study of this site, first thanks to the team of paleontologist Alberto Simonetta , and later Derek Briggs and Simon Conway Morris . The new studies revealed that the Burgess faunas were much more diverse than Walcott had ever imagined: some of these animals bore little resemblance to living animals, and many had characteristics that might strike us as aberrant.
Among the most disturbing fauna revealed by the shale of the Burgess Shale we can highlight some candidates for “monsters of the night of time”.
Opabinia
A very strange animal with a soft body, segmented as in the case of worms or arthropods, with fin-like appendages arising from each segment, and provided with gills. It had a globular head with 5 bulging eyes , a mouth, and a kind of proboscis or trunk topped by a kind of pincer. Opabinia is in fact largely to blame – or to the credit – for paleontologist Stephen Jay Gould proposing a theory in his book “The Wonderful Life” : that the extraordinary disparity of these Cambrian fossils shows that during this explosion evolution gave rise to gave rise to a greater variety than we know today. And that, after this experiment, this great adaptive radiation, many of these lineages became extinct, and that is why they are so strange to us.
Wiwaxia
Another nightmare beast from the Cambrian of the Burgess Shale is the Wiwaxia , a creature covered in carbonated scales and spines . The current interpretation considers it either an ancestor of the molluscs or of the polychaete annelids.
Hallucigenia
One of Burgess’s most fascinating creatures, and one that makes your hair stand on end because of how strange they seem, is Hallucigenia . And it is that even the name makes it clear that it looks like a hallucination: an elongated creature, with a series of paired legs or appendages on one side, and spines on the opposite. At first it was not known what the head was, what the tail was, if it walked on the spines, or on the soft appendages. He had neither head nor tail, literally. Today it is considered that it could be related to the current onychophorans.
Anomalocaris
Between 1911 and 1917, Charles Walcott unknowingly made extremely important finds of Anomalocaris at the time, only, appearing as separate fragments , he did not know that he was dealing with pieces of that enigmatic animal. And it is that, far from being a shrimp, the first fossil found and named Anomalocaris was only a small appendage of a larger animal… It was possibly the most fearsome predator of its time, a relentless hunter with fins on the sides in a similar way to Opabinia , with two bulging eyes and two jointed appendages to capture prey. In 2011, six new specimens were found in Emu Bay, Australia, including well-preserved eyes, showing that their eyes were compound , and adding weight to the hypothesis that Anomalocarids were primitive arthropods.
It may be that, over time, many of these impossible life forms have been classified as relatives of current groups, but their strangeness remains. They may not be beings from another world, nor may they all be failed experiments by extinct lineages from a world that could have been and was not.
Knowing how surprisingly diverse life is, and that not all habitats are easy to fossilize, they may have lived in even stranger forms, of which we will never know. many more fantastic animals or nightmare monsters from the night of time.
References:
Gould, S. J. 1989. Wonderful Life. The Burgess Shale and the Nature of History. Norton, New York, 347 pages.
Conway Morris, S. 1998. The Crucible of Creation. The Burgess Shale and the Rise of Animals. Oxford University Press, 242 pages.
Briggs, D.E.G. et al. 1994. The Fossils of the Burgess Shale. Smithsonian Institution Press, Washington, 238 pages.
Paterson, J. R. et al. 2011. Acute vision in the giant Cambrian predator Anomalocaris and the origin of compound eyes. Nature, 480, 237–240 (2011).
