Cladodont

Cladodont (from Latin cladus, meaning branch and Greek Odon, meaning tooth) is the term for a common category of early Devonian shark known primarily for its "multi-cusped" tooth consisting of one long blade surrounded by many short, fork-like tines, designed to catch food that was swallowed whole, instead of being used to saw off chunks of meat like many modern sharks.[1] The skinny teeth would puncture and grasp the prey, keeping it from wriggling free.

This is a typical Cladodont tooth, of a shark called Glikmanius

Because the most common fossil evidence of cartilaginous fish is teeth, this term is also used for the fossilised teeth themselves.

History
The fossil tooth of Cladodus belifer, which lived about 260,000,000 years ago in what would someday be Illinois. The roundness of the main tooth, and the small tines around it, show it to be a cladodont.

The earliest known shark, Cladoselache, was a cladodont existing about 370 million years ago.[2] It had the typical cladodont teeth, which probably also were not regularly replaced like those of modern sharks, but did appear to wear down from use. This shark did indeed appear to swallow its prey whole, fossil examples containing batches of fish arranged tail-first where the shark's stomach should be.

Around this time, the stethacanthus genus of shark also begins to appear in the fossil record. Also a cladodont, it survived from the late Devonian to the early Carboniferous, dying out about 320 million years ago.

While the earliest known sharks are cladodont, there is some evidence that they evolved from a common ancestor with "diplodonts", sharks whose teeth have two larger blades poking out, plus a small middle tine that could have become the main blade in cladodont teeth.[3]

Some cladodonts appear to have been in existence as recently as the Jurassic era.

At one point, frilled sharks were thought to be living descendants of cladodonts, but they are now believed to simply be unrelated, curiously shaped sharks, despite similarly pointy, snagging teeth.

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gollark: So the general and robust fix for this would be to stop doing I/O this way for anything but performance-sensitive and fairly robust (terminal, FS) I/O and API stuff, but PotatOS has so much legacy code that that would actually be very hard.
gollark: As it turns out, you can take a perfectly safe function with out of sandbox access and make it very not safe by controlling what responses it gets from HTTP requests and whatever.
gollark: And *another* Lua quirk more particular to CC is a heavy emphasis on event-driven I/O via coroutines.
gollark: The FS layer is actually fine, probably, apart from insufficiently flexible filesystem virtualization; the issue is that since this is really easy, many other potatOS features interact this way.

References
  1. Tooth retention in cladodont sharks: with a comparison between primitive grasping and swallowing, and modern cutting and gouging feeding mechanisms
  2. Martin, R. Aidan. "Ancient Sharks". ReefQuest. Retrieved 2006-09-09.
  3. Physiology of Elasmobranch Fishes: Structure and Interaction
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