Humans are basically aquatic mammals (Elaine Morgan...); that means, amongst other things, that many if not most places on Earth where humans have lived in the remote past might now be under the waves as is the case with the Yonaguni ruins off of Okinawa.
Having a sense of smell no better than humans possess would be fatal for any land prey animal. Notice however that aquatic mammals do not really require much of a sense of smell. Elaine Morgan listed a hundred or so traits1which we share with other aquatic mammals but there are a few which stand out:
Voluntary control of breathing which is an adaptation for swimming and diving. We take that for granted but monkeys and apes do not have it. That is the only reason they cannot teach chimps and gorillas to speak English (they can be taught to communicate using deaf signs perfectly well).
Face to face sex. Marine mammals do that, land animals generally don't.
Shoulders adapted for swim strokes. The motion to swim is the same as to throw overhand and use something like a javelin or an atlatl. Humans have that, primates and hominids never did. That is why Neanderthals were limited to thrusting spears while early humans had atlatls and javelins.
Lack of a decent sense of smell.
Elaine Morgan's aquatic ape theory can be viewed two ways. Viewed as a new version of evolution, it doesn’t really work. Viewed as a theory of human adaptation, it is the best theory that has ever been put forward, but it has never gotten any traction in academia and there are two reasons for that:
There is no fossil evidence of any sort of an aquatic ape ever having lived on this planet, and
There has never been a body of water on this planet which would be safe for humans to live in. You only need to spend 15 minutes in the ancient sea monster section of any large museum to comprehend why humans never lived in water on Earth in prehistoric times.
Perfectly good theory, it just needs a different kind of a world to happen on.
My new book is about that different kind of world...
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