Are there scientists who think that dinosaurs are not birds?

Question

I disagree that birds came/evolve from dinosaurs because many of their characteristics are similiar to crocodilians. I compared the skeletial structures and egg design between the dinosaur and crocodilian, and I concluded that dinosaurs are a unique kind of reptilian group.

Dinosaurs are just a group of reptiles that were designed in a different pattern from snakes, turtles, crocodiles, and lizards. Although they have some skeletal characteristics as birds, they are not birds.


Like many organisms, the population of dinosaurs changed, not the individual species. A dinosaur can produce a dinosaur, not a bird.

Answer 1

Umm....dinosaurs aren't birds. They are a reptile group. The way I was taught in my herp lectures was that the crocodile is the closest relative of the bird. Both are archeopteryx (sorry on the spelling, can't find my notes). Dinosaurs are different. Some smaller ones eventually evolved into bird like things, to feathers, flying, etc. There is fossil evidence for at least convergent evolution. You can't really say it was a direct connection with the evidence available now.
Dinosaurs, for the most part, are a different group. Remember that there were probably millions of species of dinosaurs of all different shapes and sizes- I am sure we do not know about all of them, and probably never will.

Answer 2

You have it backwards. The current thinking is not
that dinosaurs are birds, but that birds are the
offspring of dinosaurs. The crocodilians (I don't
know where one person who answered got the
idea that there are no such things as crocodilians)
are supposed to be the nearest LIVING relatives
of birds, but the distance between the two groups
is very great. The actual nearest relatives of birds,
according to most scientists, is some group of
extinct small dinosaurs.

Not everyone accepts this idea, however. There
are a few people who think that some earlier
reptile, such as one of the thecodonts, may have
been the ancestor of both dinosaurs and birds.
The fact (if it is one) that birds are descended from
dinosaurs, does not mean, as some people have
said, that birds ARE dinosaurs, any more than that
all vertebrates are fish, because their ancestors
were fish.

There is a large group of organisms called the
Amniota. It includes reptiles, birds and mammals.
Both birds and mammals had reptilian ancestors.
We don't really know what we would call the
intermediate species if we had one alive. There is
no place in our classifications for the connecting
links. We have to call them reptile, bird or mammal
and the best we can say is that some reptiles are
more bird-like than others and some birds more
reptile-like than others. The same with the mammals.

Answer 3

It has long been suspected, and the evidence is just about conclusive, that dinosaurs were endothermic (warm blooded) while reptiles are exothermic. Certainly the later dinosaurs were. Birds have so much in common with dinosaurs including bone structure and feathers. Feathers evolved from scales for warmth - which is a good indicator that they were endothermic.

One particular structure of birds, dinosaurs and reptiles to look at closely is the leg joint, the way the legs support the body. In reptiles, the legs come out sideways and the body hangs between the legs. In dinosaurs and birds the body is over the legs as it is in bipedal mammals. The hip joint is completely different.

Dinosaurs are very different from reptiles. While dinosaurs and reptiles had a common ancestor, the evolution of each after the split went in different directions.

If you want some really strong evidence of the relationship between dinosaurs and birds you should look at some of the recent Chinese fossil discoveries. I don't think you will doubt that birds evolved from dinosaurs and not reptiles if you study those.

Answer 4

The reason many scientists view birds and dinosaurs as simlar is because of the bone structure. Look at the way a t rex bends now look at the way a modern bird does see the similarity? Many bird looking dinosaurs had reptilian bone structure and many reptiles had bird boned structure. Scientists classified the animals and theorized this idea because of their bones. As I've been mumbling on and on.

Hope I helped

Answer 5

YES, it is a major controversy among scientists. I remember about 3-4 years ago when a group of scientists came out with the statement that maybe birds had not evolved from dinosaurs...it was all over the news, and in scientific magizine.

Answer 6

You are utterly wrong. Birds are indeed the sole remaining survivors of the dinosaurs. They have nothing whatsoever to do with reptiles, which are cold-blooded for one thing, whereas birds are warm-blooded creatures.
What's more, there are no such critters as "crocodilians". Learn biology and zoology before you pose stupid theories here.

Answer 7

How is it achieveable if humankind did no longer descend from monkeys? Monkeys are our closest 'family members', no longer our ancestors. We did have a common ancestor, and that replace right into a mammal, yet no longer a monkey. Now, Evolution says birds would have derived from reptiles.

Answer 8

The question of this bit of branching of the evolutionary tree requires attention by a specialist, so I can't give a definitive answer. The reference may be of help.