Question: What facts do you have on dinosaurs

Lucile Crete answered on 25 Apr 2021:

There is a lot that palaeontologists know about dinosaurs! (although I have to say here that I am not a dinosaur-specialist – as an archaeologist I work on time periods related to human presence, which millions of years after most dinosaurs had gone extinct!)!

If I had to summarise quickly the main facts that I know about them, it’d be:
– Dinosaurs are a group of reptiles that laid eggs, lived on land (not in the sea), and were different from lizards and crocodiles by the way they walked in an upright position, with legs perpendicular to their bodies.
– Most dinosaurs lived between about 245 and 66 million years ago, during the Mesozoic era.
– From studying the skeletons, footprints and other fossilized remains (eggshells or feathers, for example) that were found, there are at least 700 different species of extinct dinosaurs that have been identified.
– There were different types of dinosaurs: non-avian dinosaurs (those that could not fly) and avian dinosaurs (those that could fly).
– All non-avian dinosaurs went extinct 66 millions years ago, potentially due to an asteroid impact and volcanic eruptions that caused large-scale climate changes, which disrupted the ecosystem.
– Avian-dinosaurs have not entirely disappeared though, as modern birds descend from these flying dinosaurs. The oldest bird fossils are about 150 million years old, and looked like small, feathered dinosaurs with sharp teeth.Over time, birds evolved, gradually losing their teeth and developping beaks.

There is obvisouly way more that is known about dinosaurs (and yet still more to discover!), but I wouldn’t want to risk getting details wrong as it is not my field of expertise! 🙂

But if you want to read more about it, some of my colleagues have written nice short articles about it that you can access online:
https://www.nhm.ac.uk/discover/dinosaurs.html