Tillettor Tendon-Lizard

Tenontosaurus tillettorum

    At the dawn of the Cretaceous, the last age of the Mesozoic Era, flowering plants are already spreading across the globe.  These leafy shrubs and small trees with their unique reproductive systems have progressed far beyond their humble swamp-weed beginnings, and have gone a long way toward remaking the world.  Spiny, woody, cycad undergrowth is become a thing of the past, replaced by a dense mass of fast-growing flowering shrubbery.

  This shift in flora, of course, must spawn an equal shift in fauna; the old plant-eating tribes are dying out. In North America, the stegosaurs are already gone, and sauropods are becoming increasingly rare.  In their place, small ornithopods, the progeny of such creatures as Jurassic Hypsolophodon, are expanding into greater diversity.  

    Tenontosaurus  tilletorum is one of this first vanguard of new browser.  Far larger than its Jurassic ancestors, T. tilletorum is an obligate quadruped, its weight supported by fore- as well as hind-limbs.  The neural arches over its hips and at the base of its tale are large and flat, supporting powerful muscles that support the weight of the dinosaur's long, counterbalancing tail.  The spine is further supported by a network of tendons (this genus's namesake), ossified into bony struts that restrict mobility but allow a T. tilletorum to stand and run even with its great size.  

    T. tilletorum's jaws are elongated, its beak anchored against a large premaxilla and fed by countless blood-vessels.  The dinosaur's flat-headed teeth, while not as sophisticated as a hadrosaur's wedge-shaped grinding batteries will be, are more than adequate to chop through the undergrowth.  

• T. Mike Keesey's Tenontosaurus page
• Dino Data's Tenontosaurus page
• Øyvind M. Padron's  Tenontosaurus page

Baby's skull drawn from model

© Daniel Bensen 2001
This image modified by Adobe Photoshop
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