Thursday, March 18, 2010
If the ability to recognize different smells is useful to an organism, why do you think humans have about 400 hundred olfactory receptor genes that are permanently inactivated? What advantages could this have on the human race? Also, Coyne says that "we carry this genetic baggage because it was needed in our distant ancestors who relied for survival on a keen sense of smell" (71). Since evolution is driven by natural selection, wouldn't it be beneficial to stop DNA replication of this unnecessary "baggage"? What could be some reasons as to why our bodies continue to replicate 800 OR genes knowing that 400 of them are inactive?