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How many species related to dinosaurs are left in the world today, and where do they live?
Question Date: 2008-06-08
Answer 1:

The only animals living today that are thought to have descended from the dinosaurs are birds. Only recently has this theory been accepted by many scientists. 65.5 million years ago during what is called the Cretaceous-Tertiary extinction event, all of the dinosaurs went extinct and it is thought that only the avian ancestors survived (as well as many other reptiles and mammalian ancestors). Of course, the evidence for this is based off of fossils that scientists have found over the years, so it is possible that they are missing some fossils. Birds specifically evolved from a group of dinosaurs called the theropods, which were flesh-eating dinosaurs that walked on two legs that had feet resembling modern-day bird feet. As I'm sure you know, birds live pretty much everywhere on earth and the number of species is nearly countless (new ones are discovered all the time) -- it's interesting to think that whenever you're eating chicken, you're actually eating a modern-day dinosaur!

Although birds are thought to be the only living dinosaur descendants, some other animals living today are related to the dinosaurs. Dinosaurs are in the reptile group, which includes turtles, crocodiles, birds, lizards, and snakes. Of these groups of animals, second to birds, crocodiles are probably the closest related to dinosaurs (though they are not considered modern dinosaurs themselves, unlike birds). Today, there are 23 known crocodile species (which live in the tropics of Africa, Asia, Australia, and the Americas) and over 10,000 bird species in the world.

Hope that helps answer your question!

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