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Cake day: July 1st, 2023

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  • Probably too different, as snails are benthic, while ammonites where probably nektonic.

    Iirc the shells being longer is something about allowing gases in the shell to compress or expand as needed to control bouyancy. I would imagine there is a sac of gas, and the ammonites would siphon water in or out as needed to compress or decompress the gas.

    Edit: just looked it up on Wikipedia, it appears the heteromorph ammonites are thought to have maybe been planktonic or benthic.

    Definitions for non-nerds:

    Benthic means living on or near the sea floor.

    Nektonic means free swimming

    Planktonic means going with the current as plankton. I should note plankton aren’t all tiny, some are visibile to the naked eye. All it means is unable to propel themselves against current.









  • LouisGarbuor@sh.itjust.workstoMemes@lemmy.mlhold on
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    11 months ago

    Not all fish can breath underwater interestingly enough, meaning if they can’t reach air they will drown. The first example that comes to mind are lungfish, but there are others, such as arapima. I think bettas also are obligate air breathers, but I might be misremembering.