Science and life on earth

Survivors of the Last Extinction Crisis – by Richard Flament

66 million years ago, the age of the dinosaurs ended with a movie-worthy story about the end of the world. Meteors, extreme climates, and volcanic eruptions have made life so hostile to any terrestrial being, that dinosaurs died during this catastrophe. However, not all of them disappeared. A group of feathered dinosaurs managed to repeatedly withstand the climatic explosions that persisted on Earth at that time.

In popular ideas, it is common to believe that dinosaurs became extinct a long time ago, when in fact they are very different today. Heirs of a huge kingdom, these last survivors are simply all birds. So why would birds get away with it and not big dinosaurs like Tyrannosaurus Rex or other sauropods?

The main reason for the disappearance of large dinosaurs (and other living creatures during this period) is the disruption of the food chain due to various climatic events that occurred 66 million years ago. Thus vegetation, prey and predators were severely affected. Not to mention the massive asteroid that crashed in Chicxulub, Mexico, which destroyed a lot of life on impact and probably darkened Earth for years.

As for our dear birds, or “bird” dinosaurs, they managed to survive without much harm thanks to their diet other than carnivores and herbivores. At least, this is the most likely hypothesis. In fact, birds are somewhat opportunistic and therefore have the ability to prey on a variety of foods such as seeds or insects. Their breeding is also faster than that of other dinosaurs, so they will renew a new group faster.

Tens of millions of years of evolution pushed the surviving dinosaurs into what we know today about the diversity of birds. In some birds such as ostriches, emu and the helmeted cassowary, their leg morphology is used in the film to recreate what must have been the legs of a carnivorous dinosaur dating back to the secondary era. At the same time, they are dinosaurs… Who would have thought that we can still see them today?

Richard Flament, PhD student in evolutionary biology at Qatar University