Hi,
have you read Morgan's book? She implys human morphology is the direct result of an aquatic environment. Not a beach environment and not a semi aquatic existance.
It is not debated that humans are aquatic or semi aquatic that is simply a matter of semantics. When the word aquatic is used in biology it is assumed from the start that one is talking about a creature who's principal niche is in the water and not just a beach dweller. .Humans have exploited and adapted to many niches and environments on the planet. But Morgans book contends that humans evolved from a aquatic existance, not that humans lived near and on beaches and eventually learned to swim and make use of the sea as a source of food.
The fact that humans inhabit the beaches of a planet that is almost entirely composed of water is pretty much a no brainer. By that logic every creature on an aquatic planet is aquatic in orgin.
The argument is did humans evolve from a unknown, unseen ape that was aquatic as opposed to the savanna theory? The answer to that question is at this time from anthropologist is no. To assume all of Homo sapiens morphology and traits can be traced from one arboreal ape that adapted to living in the water and over time adapted back to a terrestrial existance is asking to assume a great deal. Considering there is no fossil record.
Rather than a ape that adapted from an arboreal existance to a terrestrial one . Which does show a variety of early bipedal hominids that fit the latter description. But that is just my own opinion. If people care to believe we desended from an aquatic ape then the onus is on them to produce some evidence other than conjecture and speculation. IMO.