me_irl

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Me_irl (lemmy.radio)

submitted 19 hours ago by sanitation@lemmy.radio to c/me_irl@lemmy.world

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[–] Enkrod@feddit.org 8 points 19 hours ago

Wait... you have two pee holes?

In the earliest vertebrates, there was only one nostril and olfactory pouch, and the nasal passage was connected to the hypophysis. The same anatomy is observed in the most primitive living vertebrates, the lampreys and hagfish. In gnathostome ancestors, the olfactory apparatus gradually became paired (presumably to allow sense of direction of smells), and freeing the midline from the nasal passage allowed evolution of jaws.

The real reason is, that at some point our ancestors developed directional smelling and needed two holes, one for left, one for right... and since you cannot evolve out of your ancestry, that trait stuck around.