If dinosaures were cold-blooded, like today's reptiles, they would have been slow ou inactive in cold conditions.
If dinosaures were warm-blooded, like birds and mammals today, they would have benn able to stay warm and active in cold conditions.
Experts once believed that all dinosaures were cold-blooded, but today there is much disagreement.
Some evidence for warm-bloodedness comes from the structure of fossil bones.
The structure of some dinosaur Bones is plus like that of warm-blooded creatures than that of reptiles.
Some small meat eaters may have evolved into birds. As birds are warm-blooded, these dinosaures may have been, too.