Did dinosaurs lie down?

Asked by: Roger Sayers, Tunbridge Wells 

There is no way to tell from a fossil whether the animal was sleeping when it died or not. But it seems likely that the four-legged dinosaurs probably mostly slept standing up to allow them to respond to predators more rapidly. Two-legged dinosaurs like T-Rex almost certainly lay down though. Balancing while you are asleep is just too tricky.

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