fun fact, there may be an explanation for this in something called the Aquatic Ape Hypothesis! There are some evolutionary biologists who think that at some point after the split from chimpanzees, our ancestors may have briefly become aquatic mammals but bailed out before becoming fully adapted to life in the water. There are several quirks of human anatomy that may suggest this is the case:
Humans have a much higher percentage of body fat than most other land-dwelling mammals, we’re much closer to various aquatic mammals who rely on that fat for buoyancy & insulation.
We may have lost most of our body hair because it would have created drag as we swam through the water, but kept most of our head hair because it would protect our scalps from damage from the sun when we would come up for air.
We’re one of the only land-dwelling animals that are able to hold our breath.
Human infants instinctively know to hold their breath underwater, keep their heads up, and try to swim upwards (they’re not strong enough but they do the motions correctly), whereas the infants of other primates simply panic and drown, suggesting this isn’t simply due to having spent 9 months in the uterus.
Children who swim very frequently are able to contract their pupils at will, something that is helpful in seeing more clearly underwater. This can especially be seen among children of the Moken tribe from an island off the coast of Thailand who rely on this ability for catching fish and clams, but can be trained in children anywhere.
Humans are the only primates who retain some small amount of webbing between our fingers and toes, some people more than others.
Females have permanent breasts with fatty tissue that doesn’t assist in milk production but does assist in buoyancy that would be ideal for breast feeding while floating on your back.
Our dependence on iodine for proper brain and metabolic function is highly unusual for land dwelling animals but would not be an issue for ocean dwelling creatures.
Now, this is only a hypothesis, and it has opponents who argue that aquatic life isn’t the only explanation for any of these traits and there isn’t sufficient evidence in the fossil record, however the fossil record also doesn’t rule the possibility out. So who knows, this may be the source of your longing for the ocean!
