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How long did it take dinosaur eggs to hatch? © Alamy

How long did it take dinosaur eggs to hatch?

Published: 23rd February, 2022 at 11:00
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Say you're opening a dinosaur theme park. How long would you have to incubate your eggs?

As far as we know, all dinosaurs reproduced by laying eggs. Some species, like the giant long-necked sauropods, laid dozens of eggs in a small nest, which they essentially abandoned and left to hatch on their own. Others, like the feathered raptors closely related to birds, laid a smaller number of larger eggs, and actively sat on their nests to provide protection.


But how long did it take dinosaur eggs to hatch? Until recently, palaeontologists had no idea.

A study published by Dr Gregory Erickson and colleagues answers this question for two particular dinosaurs: the duck-billed herbivore Hypacrosaurus and Protoceratops, a horned dinosaur closely related to Triceratops. By studying the growth lines in the microscopic teeth of embryos found inside fossilised eggs, Erickson and his team determined that Protoceratops eggs took about 2.8 months to hatch, while those of Hypacrosaurus incubated for 5.8 months.

Modern-day reptiles incubate their eggs for a similar period of time – often many months. Birds, on the other hand, hatch very quickly, usually within two months, and sometimes even within two weeks. Today’s birds descended from dinosaurs, but they must have evolved their hyper-fast hatching rates much more recently.

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Asked by: Tim Price, Wrexham


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