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Will cladists allow theropods to dig
QUESTION:Why would they have to rotate their palms? In order to suit your
idiosyncratic stereotype of what a digger should look like?
Digging toward your other hand is likely to result in injury. The old
kitchen adage: "Cut away from your hand." At best, your hands will be
flinging dirt at each other -- kind of counterproductive.
ANSWER: That makes no sense. Rotating the paw downward would point it towards one's
legs. Besides, one does not have to dig by swiping one's arm in a long
reckless stroke as you are suggesting. On can dig with a short, raking
stroke, which is much more effective. If you see how hydraulic excavators are
used for digging, you will notice that the operators of these equipment use
short raking strokes, not long swiping strokes when digging the hard stuff.
It appears that the designers of excavator equipment at Caterpillar (a picture
of such as excavator is provided in the link below) know a lot more than you
about digging. They have designed a small, narrow digging shovel (not the
broad ones for moving loose dirt), and reduced the digging surface further by
integrating a rake at the leading edge of the shovel. Not coincidentally,
theropod hands follow the same design. Theropod hands are prehistoric rakes,
just as Sereno and Novas suggested!
http://www.cat.com/cgi-bin/equipment_getimage.cgi?imageid=C002568_01
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