During the Cambrian Explosion over 500 million years ago, the oceans teemed with weird creatures that were busy redefining what life looked like on Earth. One of those creatures was just chiselled out of the Canadian mountains and is now one of the largest animals known from the time period.
The animal is Titanokorys gainesi, and it was built like a tank. T. gainesi had multifaceted eyes, a ring-shaped mouth that looks like a pineapple slice, claws to snap up prey, a trail of flaps for swimming, and a head covered in a massive carapace. It was a member of a primitive arthropod group called radiodonts. The fossil’s morphology and the circumstances of its discovery were published today in Royal Society Open Science.
“The first specimens were found in 2014, but it wasn’t until 2018 that we discovered a particularly pristine carapace [and] we recognised the significance of this find,” said Joe Moysiuk, a paleobiologist at the Royal Ontario Museum in Toronto and co-author of the paper, in an email to Gizmodo. “My coauthor Jean-Bernard split a particularly large slab of shale, and I recall hearing a gasp followed by a lot of yelling and everyone crowding around. We’ve found a lot of cool things, but this one really left an impression!”
The team found the fossil in Canada’s Burgess Shale, a stretch of rock in western North America that has yielded stupendously well-preserved remains of the animals that lived during the Cambrian (541 million to 485 million years ago), when the area was covered by sea. T. gainesi and other predators like it would have been filter feeders, sifting through the mud and sucking up any tasty morsels they came across.
Some of that petrified seabed, lifted up over time by tectonic shifts, now makes up the shale high in Canada’s Yoho National Park. To get the fossil down the mountain, Moysiuk said, the team wrapped it in foam, duct tape, and cut-up bits of pool noodle, then suspended the bundle from a helicopter.
Two years ago, the same team found an animal similar in shape to T. gainesi; they named it Cambroraster falcatus for the way it resembled Han Solo’s Millennium Falcon. The shale preserves even the soft tissue remains of those Cambrian creatures, meaning that paleontologists can study itsy-bitsy evolutionary relics in greater detail than they can in many dinosaurs, which turned up some 300 million years later. (Yeah, there’s more time separating the first dinosaurs from the Cambrian period than there is separating those dinosaurs from us!)
Perhaps the most impressive feature of T. gainesi is its size. Most animals that inhabited the Cambrian oceans were smaller than a pinky finger; this one is about a foot and a half long. If the typical Cambrian critter were the average human height, a T. gainesi in relative proportion would be nearly 12.19 m tall.
“The sheer size of this animal is absolutely mind-boggling, this is one of the biggest animals from the Cambrian period ever found,” said lead author Jean-Bernard Caron, a paleontologist at the Royal Ontario Museum, in a museum press release.
“These enigmatic animals certainly had a big impact on Cambrian seafloor ecosystems. Their limbs at the front looked like multiple stacked rakes and would have been very efficient at bringing anything they captured in their tiny spines towards the mouth. The huge dorsal carapace might have functioned like a plough,” Caron added.
You can imagine the creature as a massive carnivorous zeppelin, floating just above the seafloor as it dredged the muck for food. The discovery expands the team’s knowledge of predators with carapaces during the Cambrian period; for the sake of everyone who loves nightmare creatures, let’s hope they find more.