NORTH POLE DINOSAURS LIVED SHORT, HARD LIVES

By counting tree-like bands on femur fossils, paleontologists can estimate dinosaur growth stages.
Some North Pole dinosaurs grew fast as juveniles, became sexually mature at age 9, and died at around 19.
Northern Alaska during the latter Dinosaur Age was slightly warmer than it is now, but still experienced freezing temperatures during long, dark winters.

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