[Lev]

There could have been numberous improvements to them that would have been helpful - a smarter brain, better fins, changes to make it reproduce more or better.

Do you know what local maximum on a fitness landscape is?

[gore3000]

Do you know what local maximum on a fitness landscape is?

No, but to paraphrase the Supreme Court on pornography: I know BS when I see it.

[Heartlander]

"Sometimes, the "just so" stories are backed by computer models using random combinations and selection advantages. However, the computer models are always too simplistic compared to biological systems. Also, many of these programs rely on intelligent input that natural selection could not duplicate. These attempts at computer modeling also still don't address an old problem. Many years ago, this problem was noted by a group of mathematicians. They could not derive a probability pattern that would make natural selection a likely means for evolution of complex biological systems. This contention has never been overturned."