I don’t have any real disagreements with the points you make there, but I do think this statement could mislead some:
Provolution—has led gradually from primitive simplicity to the powerful adapted complexity of modern living things
Loss of complexity can certainly be adaptive too, as I think you acknowledge here:
What about a cave fish losing its sight? Is that devolution? If it is losing its eyes because doing so saves energy and is adaptive—which is quite likely—that would not be devolution in the sense described here.
Also, interesting to note that one cave fish, Astyanax, seems to have lost its eyes not to conserve energy, but because of pleiotropy: the same genes used in eye development are also involved in other traits, like sense of taste, and mutations which produce improvements in taste simultaneously change eye development. It’s hazardous to talk about the fuction of something before you know how it’s made!
I don’t have any real disagreements with the points you make there, but I do think this statement could mislead some:
Loss of complexity can certainly be adaptive too, as I think you acknowledge here:
Also, interesting to note that one cave fish, Astyanax, seems to have lost its eyes not to conserve energy, but because of pleiotropy: the same genes used in eye development are also involved in other traits, like sense of taste, and mutations which produce improvements in taste simultaneously change eye development. It’s hazardous to talk about the fuction of something before you know how it’s made!