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Re: REALLY good introduction to cladistics!!
Followed the link and took the student tour.
Can you really call that a third digit on T. rex's 'hand'?
Appears to be a java site where I had to back up only 3 or 4 times; as
usual, pages failed to download completely, and 'Refresh' puts you back
Anyway, the part that bothered me was in the section in which the lesson is
discussing animals with 2 windows in the skull. The lesson asks how you can
tell animals are related if one of the windows has disappeared. The answer
given is 'Fossils!'. Going back to the ancestors of the animal without the
second window (quicker to say than quoting 'hole in the skull') will show
animals with the second window.
How you prove an ancestral relationship is left out of the discussion
entirely. Probably too complicated for the very simple approach used, but a
definite loose end, you ask me.
And of course, I was waiting for the 60 page explanation of why certain
characters are included and others left out, and how the coding is
decided... Must be in the teachers' track, I guess.
Checking that next.
Oh, and amniotic egg is coded '?' for T. rex. Be a major disappointment if
they laid eggs fixed to lily pads.