Dinosaurs Used Sunlight and Body Heat to Hatch Their Eggs 70 Million Years Ago

Scientists have recreated a life-sized oviraptor and egg nest to better understand how these bird-like dinosaurs incubated their eggs about 70 million years ago.

A study published in Frontiers in Ecology and Evolution examined whether oviraptors relied on environmental heat, like reptiles, or body warmth, like modern birds.

Researchers in Taiwan combined heat-transfer simulations with a full-scale experimental setup using a model dinosaur and artificial eggs.

The team based the design on Heyuannia huangi, a species that lived around 70 million years ago and laid eggs in semi-open nests. Because the egg arrangement prevented full contact between adult and eggs, scientists found that not all eggs received the required heat to hatch.

Experiments showed that in colder conditions, temperature differences between eggs could reach up to 6°C, leading to uneven, or asynchronous, hatching. In warmer conditions, differences dropped to about 0.6°C, suggesting sunlight played a key role in incubation.

The findings indicate oviraptors likely used a combination of limited body heat and environmental heat rather than fully brooding their eggs like modern birds.

This method was less efficient but suited their nest structure and environment.

Researchers concluded that oviraptors did not incubate eggs in the same way as modern birds, highlighting a distinct reproductive strategy rather than an inferior one.