[_Stefan_]

The earliest fossil bats are about 52 million years old. These bats already looked similar to modern bats, so they had to have been evolving into bats some time before this. However I would suggest that they waited for the dinosaurs to go exinct before they did so, since the majority of new mammal forms followed this evolutionary pattern. 15 million years is a long time.

[Don_1]

Being mammals, as Stefan has said, the bats probably had to wait for the demise of the dinosaurs before they could take to the skies.

There is fossil evidence of bats up to 54 million years old. These earliest bats did not have the echo location ability of today's bats, but they were already pretty close to modern bats. That fact would suggest that there are earlier examples yet to be found.

I would suggest it very likely that the bat evolved from a shrew like tree dweller which, like the modern flying squirrel, developed the ability to glide in the first instance.

[_Stefan_]

Perhaps David Attenborough was referring to these reptiles, rather than dinosaurs? http://en.wikipedia.org/wiki/Mosasaur

[rosalind dna]

Perhaps David Attenborough was referring to these reptiles, rather than dinosaurs? http://en.wikipedia.org/wiki/Mosasaur

This is the programme that David Attenborough was referring to reptiles from and creepy crawlies too. http://www.bbc.co.uk/programmes/b00nj6dr
It is about living animals

[Monox D. I-Fly]

The closest living relatives of dinosaurs are Archosaurs. http://en.wikipedia.org/wiki/Archosaur

Reading the name, I never thought that it was a bird. I thought it was a turtle/tortoise whose body looks like a lizard because I thought that Archosaur = Archelon + Sauros

[NakedTruth]

I would say that crocodiles and insects are here since that time. A very long time

[axscientist]

Birds are relatives with quite a few prehistoric animals, such as the coelurosaurs. Scientists nowadays say that birds are just like living dinosaurs in the modern era.

[xatajam823]

Komodo dragons have only been around for 40 million years.