I loaded a bunch of TED Talks on my IPod for a recent trip. One of them was by Elaine Morgan. She's a proponent of the Aquatic Ape Hypothesis. I hadn't ever heard of this. The basic premise is that if we had evolved in the water for some part of our evolution, it would explain a few issues such as the difficulties in beginning to walk bipedally, what happened to our hair, our hooded noses, narrow shoulders, subcutaneous fat, etc. It's really an interesting talk. She's a strong advocate and borderline indignant about science's wide rejection of the hypothesis.
Since I hadn't heard of this, I'm curious as to solid refutations of the idea. Anyone discussed it at length in a class? Read a great paper on it? Off hand, my brain is trying to wrap itself around the timeline of Ardi and Lucy being bi-pedal, Any chance they fit any part of Aquatic Ape Hypothesis? Any chance of cross breeding and keeping us as one species while some of these changes happened? I'd like to get a better understanding of this if someone feels like they have a grasp on it.
Here is the vid and the Wiki-link which includes criticism of it.
Well I'm not inferring anything like Aquaman or the sort. I simply question that a yet to be found fossil on the eastern cost of Africa that shows where certain evolutionary traits came from is beyond the realm of possibility. It's not like she's saying aliens made us. I'm sorry if I'm talking out of my ass here, admittedly I have no credentials or any sort. But what is making me so interested is why such an innocuous theory/hypothesis has garnered such ire from the scientific community. Such an ire that has her pegged as a crackpot for positing only that some of our early ancestors were coastal faring and adapted to their habitat. It really is very reminiscent of religion's staunchness and inability to entertain new ideas. Kinda weirds me out.
I'm not saying that you are inferring Aquaman, just that there is a big body of aquatic mythology of which science would be prudent to steer clear. The problem with this theory is that, even if true, the fossil record may never reveal any evidence. We are talking mostly about soft tissue changes that just wouldn't be preserved by fossilization. That being said, where would one even begin the search?
On some matters science simply has to say, "We don't know". Intellectual honesty demands it. Inserting things like AAH would be akin to inserting ID, and there is a commitment to intellectual integrity that may come across as stodgy but truth demands that stodginess. There is no reason to avoid holding the idea on a back burner, but without solid evidence there is just no room for it at the front of the stove.
Actually, to quote, "Humans seem hairless not because of a lack of follicles but because of the predominance of vellus fibers which are thinner, shorter, and more transparent than terminal fibers. The density of human hair follicles on the skin is about the average for an animal of equivalent size."
One hypothesis for the reduced size etc. of human body hair seems to involve running.
I'm guessing sexual selection played a part as well. Less hair = easier to see the condition of your potential mate. Might also explain why different ethnicities have different rates of hairiness. Also, less all-over body bugs.
"Another hypothesis for the thick body hair on humans proposes that Fisherian runaway sexual selection played a role (as well as in the selection of long head hair), (see types of hair and vellus hair), as well as a much larger role of testosterone in men. Sexual selection is the only theory thus far that explains the sexual dimorphism seen in the hair patterns of men and women. On average, men have more body hair than women. Males have more terminal hair, especially on the face, chest, abdomen, and back, and females have more vellus hair, which is less visible. The halting of hair development at a juvenile stage, vellus hair, would also be consistent with the neoteny evident in humans, especially in females, and thus they could have occurred at the same time."
I've always wondered if there were primitive men and women tripping on their hair before sharp objects were invented, or if head hair that grows past our feet is a relatively new characteristic, perhaps a secondary trait of sexual selection?
Regardless, interesting stuff. I enjoyed the aquatic ape ted talk as well as the refresher on the weirdness of human hair (or lackthereof).