Quoting Anthony Docimo <keenir@hotmail.com>:
Nowadays, many gliding species (at least of mammals) go horizontal while gliding....but when they are about to land on the next tree trunk, they arch their bodies so their hind legs hit the tree first.
With the hypothetical rats, it was a short step from such gliding, to gliding rats that developed hind-claws -- just like the maniraptors.
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Dann Pigdon GIS / Archaeologist http://heretichides.soffiles.com Melbourne, Australia http://www.geocities.com/dannsdinosaurs ___________________________________________________________________