Cambrian Explosion: a new monster form (Introduction)

by David Turell , Thursday, September 09, 2021, 18:50 (961 days ago) @ David Turell

Recently found:

https://www.science.org/content/article/early-ocean-predator-was-giant-swimming-head?ut...

"The half-meter-long arthropod, described in a study out today, was essentially a giant “swimming head” that prowled the Cambrian seas half a billion years ago, says Joseph Moysiuk, a paleontologist at the University of Toronto (U of T) who helped uncover the fossil in 2018. “The first word that comes to mind when I think of this new species is big.”

"Titanokorys gainesi, whose head takes up nearly half the length of its body, was covered in a domed, spike-tipped carapace that inspired its Latin name: “Titan’s helmet.” The creature likely swam along the ocean floor, Moysiuk says, flushing prey from the mud with appendages built like “baskets of spines” (see video, above). And whereas its spiky helmet might have helped with that digging, its eyes, which sat at the back of its carapace, facing straight up, would have been useless for finding prey. Those were probably for spotting other predators—threats to Titanokorys itself.

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"Titanokorys belongs to a diverse group of arthropods called radiodonts that split from the ancestors of spiders, insects, and horseshoe crabs by 520 million years ago, soon after the Cambrian explosion of animal diversity. At a time when vertebrates—the lineage that led to us—were little more than pinkie-size fish, radiodonts terrorized the Cambrian seas. The ranks of these now extinct creatures included Anomalocaris, a predator with front-facing eyestalks and a pair of clawlike appendages on its face, and Cambroraster falcatus, the species with the sleek head carapace reminiscent of Han Solo’s spaceship.

"All radiodonts shared three traits, Caron says: a circular mouth that looks like a pineapple cross-section and contains flesh-ripping teeth, a pair of spiny appendages in front of the mouth, and large compound eyes. This new species fits all those traits onto a supersize, carapace-covered head. Allison Daley, a paleontologist at the University of Lausanne who was not involved in the new research, says she is “delighted” by the find.

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"Finding Titanokorys at the same site as Cambroraster underscores the diversity of Cambrian ecosystems, Caron adds—and the remarkable abundance of predators. Earth’s early seas must have had enough prey to feed a large range of hunters coexisting in the same space, including some animals that have so far eluded paleontologists."

Comment: The Cambrian still has new organisms to find. Same old Darwinian specter, no predecessor like it.