On pages 199-201, Elaine Morgan describes a theory on how humans evolved into how we are today as a species because we were evolved from aquatic apes. Being able to live on water and land would give prehuman ancestors options to avoid predators in the water and land, increasing its chances of surviving and reproducing. The selective advantages of being bipedal are that an ape can move across water well while still breathing. The selective advantage of why our fat is attached to our skin is because it helps keep babies afloat just like dolphins flow smoothly through water.The water ape theory relates to big idea #1, the process of evolution drives the diversity and unity of life. The theory tries to explain why humans evolved the way we did instead of staying 4 legged and fury like many other animals.
Find more selective advantages or disadvantages of how humans evolved to this day for other examples(ex: big heads, shape of human pelvis, opposable thumbs). Also, explain why you think other aquatic animals didn't evolve to become bipedal like we are.Make sure to also state why you think the aquatic ape theory could be a valid way of explaining the origins of many traits that humans have today.
(Eric Huang, ehuang4@students.d125.org)
Selective advantages that humans have developed include enlarged brains, the ability to vocally communicate, skin tone, and upright walking.
ReplyDeleteA probable reason why other animals didn't evolve to become bipedal is that they were already adapted to their habitats. Our aquatic ape ancestors may have been in an environment where conditions selected for organisms that displayed bipedal traits, while other organisms in different habitats weren't selected for the trait due to differing selective pressures.
The aquatic ape theory is a valid way of explaining the origins of many traits that humans have today. Some examples of proof include; how babies are sometimes born with webbed fingers and hands; the genetics for webbed digits are within our DNA and are usually shut off by our genes. This webbed characteristic would've been beneficial in an aquatic environment, but not in today's present human environment.
Another piece of evidence is that humans are hairless. Although we have hair, the amount of it when compared to other primates is nearly insignificant. This lack of hair could be accounted for by our aquatic ancestry; the lack of hair on the body allowed organisms to increase their efficiency of movement within water.
In general, all these topics relate to Big Idea #1, in which the process of evolution drives the diversity and unity of life. Specifically, we explore how the process of evolution could have impacted our ancestors (if they were aquatic) to evolve into bipedal organisms.