Discoveries

February 16, 2023

Love ‘Em and Leave ‘Em

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Titanosaur mothers had unusual breeding habits – they buried their eggs and likely left them, says a new study.

A research team discovered more than 250 eggs in what is now central India, which offer new insights into the reproductive behavior of the massive, long-necked dinosaurs, Live Science reported.

Following a series of field investigations between 2017 and 2020, the team suggested that around six titanosaur species used that area – once a riverbank – as their nesting site. And they packed the eggs so tightly that it was possible that soon after laying the eggs the mothers abandoned their brood to avoid crushing them while navigating that narrow space.

The researchers also noted some resemblances in egg-laying behaviors between titanosaurs and present-day crocodiles, namely both laying their eggs in a clutch and partially burying them, helping incubate the eggs through solar radiation and geothermal heat. Both would also lay them near water bodies.

But the discovery of a rare “egg-in-egg” specimen also raised questions about the dinos’ similarities to birds.

Egg-in-egg occurs when an egg that is ready to be laid is pulled back into the mother’s body, and becomes implanted in another, still-forming egg. This hasn’t been documented in other reptile species, so it’s possible that titanosaurs had a similar reproductive system to those of modern avians, the researchers added.

Still, further questions remain about the findings, including whether the site was explicitly for nesting and whether these eggs were laid at the same time or over many years.

This story originally appeared in the February 16, 2023 newsletter, When the Earth Moves.