Itchy dinosaurs
Q: Can a dinosaur scratch its own itch?
 A:
Sure it could, back when dinosaurs roamed our planet. Rolling in the dirt--like elephants do-is one way. (By the way,
elephants also grasp sticks with their trunk and scratch places hard to reach.) Smaller dinosaurs probably scratched with their
hands. See illustration of a poor Sinosauropteryx, whose feathers are infested with small parasites.
[© Berislav Krzic, used with permission] A scratching Sinosauropteryx
Apparently tiny mite-like creatures plagued feathered dinosaurs just as they do birds today.
"We have now found microscopic egg-like structures on the surface of a fossil feather of approximately 120 million years old..."
report David M. Martill and Paul G. Davis in a recent article ("Did dinosaurs come up to scratch?") published in Nature magazine.
I ask Martill if dinosaurs scratched and how they managed.
"Of course, dinosaurs were infested with lice and mites and, no doubt, many as yet undiscovered parasites," he says. Large bugs plagued pterosaurs, the furry,
flying creatures of the Mesozoic skies. The fingers of a pterosaur, however, were halfway along their wings. They had to land to scratch.
The theropods ( flesh eaters) probably were best equipped among the dinosaurs for scratching. Claws extended from both their hands and feet and they could
reach most body parts. Only those with the stiffened tails, such as Velociraptor, may have failed to reach parts better scratched by "an intimate friend," says
Martill.
The big sauropods (largest of all the dinosaurs) may have had places, too, where a scratch was nigh on impossible and resorted to rolling around in the dirt like
an elephant.
Animals like the iguanodon (massive plant eaters with a horny beak) and the hadrosaurs (duck billed with hatchet-shaped ,hollow, bony crests) had stiffened
backbones that allowed them to run on two legs, like us, but made reaching the middle of their back difficult. The neck was not excessively long and neither
were the arms.
Bears overcome this by rubbing their backs against trees. But what of a dinosaur with a six-foot sail along its back, like Spinosaurus or Ouranosaurus? "Perhaps
there were pterosaurs happy to pick off insects like the oxpecker birds of today," says Martill.
(Answered by April Holladay, science correspondent, May 30, 2001)
Further Surfing:
Dinosaur Illustrated Magazine: Lousy dinosaurs
ZoomDinosaurs.com: All about dinosaurs
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