Dinosaurs Were Not in Decline Before the Asteroid Impact, Study Finds
A new study published in Current Biology challenges the long-standing belief that dinosaurs were already declining in diversity before their extinction. According to researchers, the perception of a decline may be due to gaps in the fossil record rather than actual population loss.
Key Findings:
- Fossil Record Limitations
Scientists argue that poor fossilisation conditions and limited exposure of late Cretaceous rock layers have made dinosaur fossils from that period difficult to preserve and uncover. - Misleading Data Trends
While earlier fossil data seemed to show a drop in dinosaur diversity before the asteroid impact, researchers now believe this trend may be misleading due to incomplete fossil records. - Large-Scale Fossil Analysis
The study examined over 8,000 dinosaur fossils from North America, covering the Campanian age (83.6 to 72.1 million years ago) and the Maastrichtian age (72.1 to 66 million years ago). - Focus on Major Dinosaur Families
Researchers specifically analyzed fossil data from four major families: Ankylosauridae, Ceratopsidae, Hadrosauridae, and Tyrannosauridae.
Their findings showed a peak in diversity around 76 million years ago, followed by a noticeable decline leading up to the asteroid impact. - No Environmental Evidence of Decline
Importantly, the study found no environmental or ecological indicators that would explain a genuine drop in dinosaur populations during that period.
Conclusion:
The research suggests that dinosaurs were not on the path to extinction prior to the asteroid event. Instead, the apparent decline in diversity is likely the result of incomplete fossil records. These findings highlight the need for cautious interpretation of paleontological data when reconstructing prehistoric life.
