Over millions of years of existence, the extinction of dinosaurs was not due to their size, strength or ferocity, but because the way their eggs were formed was detrimental to the species. Today, birds have become adept at incubation, but new research published in the journal Frontiers in Ecology and Evolution shows that these egg layers were ‘inefficient’ in their methods of hatching eggs. Using advanced 3D modeling of nests and actual nest building materials, researchers showed that dinosaurs were not able to effectively transfer their body heat to their eggs; Rather, they depended primarily on geothermal heat to maintain temperatures high enough for their eggs to develop and hatch. As a result, dinosaurs had a long incubation period of about six months. Given the rapidly changing nature of the Earth, the inefficient way in which dinosaurs would have laid eggs created major obstacles for dinosaurs to persist as a species.
Inside the experiment that tested how dinosaur eggs hatched
Dr. Tzu-Rui Yang of the National Museum of Natural Sciences of Taiwan created a life-size dinosaur root model to study how dinosaurs incubated their eggs. They created an Oviraptor that weighed 20 kilograms and placed it in a nest containing 30 artificial eggs. They used heat monitors and computer-simulated models to measure how much body heat was present in the eggs and how much of it actually reached the babies.
Problem with nest design
According to Frontiers in Ecology and Evolution, the way dinosaurs built their nests was not very effective at keeping their eggs warm. Today birds will hatch their eggs by sitting directly on them. The dinosaurs would sit in the center of a circular shaped nest and position themselves in the center of the nest. As a result, the only eggs that were laid the warmest were those located under the parent’s chest. In contrast, eggs located at the outer edge of the nest will be the coldest and will grow much more slowly than other eggs.
Dinosaurs rely on the sun for help
Since the parents were unable to maintain adequate heat for all of their eggs, dinosaurs depended on the Sun and the warm Earth to complete the heating process. The eggs were described by researchers as ‘a collaboration with nature’. This process worked well when the temperature was high. However, climate change has caused many problems for these eggs. When clouds block sunlight from reaching them, the eggs cannot maintain a constant heat source from above to hatch properly.
The trap of waiting three to six months
According to the study, the time it takes for the eggs to successfully hatch may also contribute to the extinction. Current birds hatch from eggs over a period of a few weeks, whereas these dinosaurs took three to six months to begin incubation. After Earth experienced a massive asteroid impact that caused catastrophic changes to its environment, dinosaurs could no longer reproduce at a fast enough rate to survive. Small animals such as birds and mammals were able to lay eggs and grow faster, allowing them to grow in population and dominate, while the dinosaurs continued to decline.