Nick Palmer wrote: <snip> However, I posted one example > that has always bothered me, to whit the process of butterfly > metamorphosis. Inside the chrysalis, the body of the caterpillar breaks down > almost completely and reforms into something very different and, on the face > of it, more complex. I could never see that this process could evolve in > small steps that were evolutionarily advantageous at each stage. The only > response I got was hand waving from some boy wonder science geek who said > that evolution has been proved as a theory therefore metamorphosis must have > evolved (without actually suggesting how)!
For the butterfly and similar cases, my understanding is that there are essentially two organisms. The cells of the adult stage exist within the body of the catepillar stage. When the metamorphosis takes place, essentially the catepillar stage dies and its body dissolves, providing nutrients for the formerly dormant cells of the adult stage to grow. How this 'evolves' is as much of a puzzle as the symbiosis of specific insects and specific orchids, which grow features in their blooms resembling the females of the insect species and generate scents similar to the pherenomes of the females. The deluded males, in trying to mate with the orchids, pollinate in the process. How these two members of different kingdoms develop this symbiosis defies easy 'explanation'. Mike Carrell
