|MadSci Network: Zoology|
Dear Asim, Your question -- are gorillas more muscular because they have more testosterone -- implies that a human with enough testosterone could develop the same muscle mass as a gorilla. It's not going to work that way. Within humans, we have a range of body types. Some of us will have the potential to be professional bodybuilders and football players, and many of us won't. I certainly don't. Megadoses of testosterone might make me more muscular, but the effect would saturate at some point, probably shy of Refrigerator Perry. There's an interesting theory that a defective gene, causing smaller jaw muscles, allowed humans to develop larger brains -- http://faculty.washington.edu/chudler/brainexp.html describes the evidence. The question is then why did we "lose" the mass in the rest of our muscles? Did the defective gene affect other muscles, or did our musculature co-evolve with the developing brain in order to be more amenable to sophisticated control?
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