Ammonoids, ancestors of today’s octopus, squid and cuttlefish, bobbed and jetted their way through the oceans for around 340 million years beginning long before the age of the dinosaurs. If you look at the fossil shells of ammonoids over the course of that 340 million years, you’ll notice something striking—as time goes on, the wavy lines inside the shell become more and more complex, eventually becoming frilled almost like the edges of kale leaves.
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Source: Phys.org