Sinovenator

Sinovenator was a diminutive basal troodontid that inhabited the lush, temperate forests of Liaoning, China, during the Early Cretaceous, approximately 125 million years ago. Measuring around one metre long and weighing only two to four kilograms, this chicken-sized predator possessed numerous primitive skeletal traits that bridge the gap between basal paravians, dromaeosaurs, and derived troodontids. Its slender jaws carried small, sharp teeth that were well suited for grasping insects, small lizards, and early mammals. Multiple remarkably preserved fossil specimens have been recovered from the Yixian Formation. These skeletons show that Sinovenator was fully bipedal, lightweight, and almost certainly blanketed in advanced pennaceous and downy feathers. It was an agile runner on the forest floor, using its speed and sharp senses to avoid larger contemporary predators.

Provides key transitional anatomy showing that troodontids, dromaeosaurs, and early birds share common dromaeosaurid-like ancestors.

Where and when

Sinovenator lived in the Early Cretaceous, from 126 to 122 million years ago (Barremian-Aptian age). Its remains come from China, in the Yixian Formation.

The numbers

Length 1.1 m (estimates run from 0.9 to 1.2 m). Mass about 2.8 kg. Hip height about 0.35 m. That is 0.6 human-lengths, or 0.1 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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