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ORAS ARE NOT DINOSAURS



Last week the Discovery Channel ran, as part of their FANGS series, a new and
unusually well done program on the the ora, a.k.a. Komodo Dragon. Low key and
full of natural history, rather than the overly dramatic narration many
nature documentaries are prone to. Also accurate in content, that W.
Auffenberg (author of the primaty text on oras) was consultant did not hurt.
Why, the even said that the ora is NOT a close relative of dinosaurs! They
did say that oras are probably the closest thing alive to big theropods in
the way they consume carcasses. Also, their use of virtually toxic (bacteria
loaded, copious) saliva may be theropod like, or maybe not. Female oras also
defend their nests for a period of time, but give no care to their young. 

What was also interesting is how undinosaurian oras are. Of course there is
the very different head body plan - flattened head, straight neck, long low
body on sprawling/semi-erect legs. Also noticable is how small the leg
muscles of oras are compared to big mammalian predators. Reptiles cannot
oxygenate large muscles, and they use intense anaerobic power production to
achieve intense but rather brief bursts of activity. But what is most
interesting about oras is how very SLOW they usually are. Every once in
alwhile they engage in bursts of spectacular speed and combat. But most of
the time they walk in the typical, stable, slow reptilian gait. I have been
catching every program with monitors in them I can so I can time the bugger's
speeds, and my sample of ~100 shows that they normally plod along at just
0.5-2 km/h. (Any student out there whom wants a thesis project plus
adventure? Travel to Indonesia and time the normal speed of movement of the
oras, including different ages and sexes, etc.) Even when they are
approaching or are feeding around a carcasse, or are disputing a nesting
site, the main mood seems to be "take it easy, no need to get THAT worked up
about it". Very different from the often frenetic activity of big mammalian
predators squabbling over the spoils. Also very different from the speeds
recorded in multitudes of dinosaur trackways, which are a mammal-like 2-10
km/h. So dinosaurs were much more active and fast walking than oras and other
land reptiles, which as I have noted elsewhere means the dinosaurs needed
aerobic exercise capacities above the reptilian level. The notion that some
reptiles are "very active" in a manner approaching mammals is a myth. Also
dubious is the proposition that dinosaurs achieved activity levels well above
the reptilian level with reptilian energetics. 

GSPaul