Whale evolution: Now there's a story without legs ...
A student wrote to me recently to ask whether I thought that whale evolution was now well understood - don't the funny little vestigial legs on some early whales explain how it all happened? I replied,
The problem with whale evolution, as one scientist explained to me a couple of years ago, is that the "legs" thing isn't actually that important.
Legs are appendages (= useful but not necessary for life). Life forms can have appendages or not have them. Check out legless lizards and you will see what I mean.
The big issue with whale evolution is the some forty or more key changes that must occur simultaneously that adapt a land animal to marine life and to diving to deep levels of water while maintaining normal metabolic processes.
Also - and this is a pet peeve of mine - the scientist happened to mention in his presentation "the whale cow must also know how to bring her baby to the surface and start it breathing ... "
I got hold of him afterward, and asked, "So HOW does the whale cow know that she must do this?
If most whale cows did not know it, the species' duration on this planet would abruptly end. So, given that whales exist, how exactly did whale cows - not individual Einsteins in their own right - acquire this vital information? Not, I suspect, from prenatal lectures."
He admitted that it was a good question.
Essentially, I don't have any answers except to say that the certainties of current public broadcasting science programs will probably not bear up under serious scrutiny.