Two ink sacs from 160-million-year-old giant cephalopod fossils have been found to contain an identical melanin pigment to that found in the ink sac of modern-day cuttlefish.
The finding suggests the ink-screen escape mechanism of cephalopods such as cuttlefish, squid and octopuses, has not evolved since the Jurassic period, and that melanin could be preserved intact in the fossils of a range of organisms.
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