Why are dinosaurs the only species that didn't survive the cataclysmic event that made them extinct?

Question

In other words, why aren't there dinosaurs today but millions of other animals who did survive?

So, what was the determining factor in what species survived and what didn't?

Answer 1

dinosaurs aren't a specie, they are a group of animals, more on the level of an order, or two distinct orders as there are two main groupings of these creatures (for comparison, rodents, carnivores, primates are orders). Ammonoids are another important group of animals that disappeared in the cretaceous extinction. Most animal groups suffered only partial extinction.

There is some open question about how one should regard birds, as they are clearly related to some dinosaurs in structure and apparently in descent.

Why did the animals that died out get destroyed, you ask? Bad luck is about as good an answer as any. No one can say for certain, but many causes have been suggested. Clearly the large animal species had difficulty adapting to the extensive habitat destruction or whatever stress occurred on a global scale, but that explanation fails to explain the loss of many other species (and some higher taxonomic groups), or the apparent thriving and rapid radiation of other groups..

Scientists don't know everything yet, or they wouldn't have jobs. (my poor effort at humor).

Answer 2

They aren't the only species that didn't survive. As many as half of the species on earth were wiped out in whatever event took the dinosaurs out.

Answer 3

I not only agree with the previous answers I will add that not all the dinosaurs died. Some may have adapted and became many forms of modern birds.

There may in fact be a direct lineage between modern *raptors* as hawks and surviving small *raptors* that went from being land based predators to modern "birds of prey."

IOW's not all dinosaurs went extinct either, some evolved like the more successful mammals did.

Also the KT event is not the only catastrophe in the geological record and not the only time of great extinctions.

The dinosaurs themselves may have begun on a previous example of such an event, just as we can thank the KT event for the mammalian rise to dominance on the planet.

Answer 4

70% of all land species died. The ones that survived were adaptable enough to handle the extreme heat/cold cycles and limited, changing food supplies that followed the impact.

Answer 5

Why do you assume that all other species survived. No one knows for sure.