Posted by Carlos Javier on December 31, 1996 at 00:06:57:
In Reply to: vestigial organs and instincts posted by Amanda on December 30, 1996 at 18:06:56:
: I'm trying to make a list here of the organs and instincts we possess that are remnants of our ancestors though no longer useful to a large degree - I've read that there are 180 odd such structures in the human body of which the appendix is one. Also, the idea that the pineal body located at the base of the brain once might have been a third eye is an interesting theory I'd like to know more about. As for instincts - the desires to crawl and cling to things which is seen in infants are supposedly examples of such as well as the instinct of fear that many of us posess. I agree that fear serves a useful purpose in the modern world to some degree but I think that perhaps we have too much of it. I can understand how it was certainly more useful in the primitive animals - in this area I'm interested in the idea that instinct was around before reason which is no doubt the case and that often our instinct will overcome our reasoning in the different examples of fear. Then there's the hypothesis that religious systems have made the most of the instinct of fear and that in order to obtain freedom from this ancient heritage we need to have our rational mind control our instinctive behaviours. Any info or opinions on this subject would be appreciated.
I can think of the lungs (modified fish swim bladders) and the ears (modified fish gills), for starters. They're not specifically vestigial, but are certainly clear indicators of human evolution.
Our cravings for sugar and fat are remnants of a time when our ancestors were engaged in a daily life-and-death struggle to get as many calories into their bodies as they posibly could. Though we now can get all the calories we need (and then some), our genes don't know that.
I can give you more later. Gotta go, now. Great topic of discussion. I'm sure plenty of folks will be happy to list more for you. Zai jian.