this post was submitted on 08 Nov 2023
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I actually fact checked this and it's true.

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[–] miss_brainfart@lemmy.ml 52 points 1 year ago (1 children)

And then you add the fact that sharks have barely evolved because they've been the perfect silent killer since the dawn of time.

Another fun fact:
Sharks don't make sound. They don't have any organ for the purpose of making sound. That is creepy as all hell.

[–] Gladaed@feddit.de 13 points 1 year ago (2 children)

Just because they didn't change their appearance doesnt mean they did not evolve. It is somewhat misleading to say that, but conveys a point I guess.

[–] miss_brainfart@lemmy.ml 6 points 1 year ago

I made sure to say barely instead of not at all, but you're right, there was certainly some evolution happening

More relevantly, the fossil records for sharks are mostly their teeth and jaws, because all their other bones are cartilage and rarely fossilize.

"Sharks haven't significantly evolved in appearance in 350 million years" is therefore based on reconstructions made under the assumption that the old sharks mostly looked like current sharks, which may or may not be true.

Though we can get a surprising amount of information that way, for example one change is that their jaws used be more at the end of their snout instead of more underslung like today, like so:

https://www.smithsonianmag.com/science-nature/new-technologies-reveal-strange-jaws-prehistoric-sharks-180977396

You'll note the Goblin Shark still has hints of that design.