A new study finds that dinosaur eggs took between 3 - 6 months to hatch - twice as long as predicted from bird eggs of similar size. Those incubation times likely made it tough for them to outcompete faster generating animals, such as modern birds and mammals, in the aftermath of a mass extinction.

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A new study finds that dinosaur eggs took between 3 - 6 months to hatch - twice as long as predicted from bird eggs of similar size. Those incubation times likely made it tough for them to outcompete faster generating animals, such as modern birds and mammals, in the aftermath of a mass extinction.