How did Dinosaurs become birds?

Question

Just been looking an an now closed qeastion, am I right in saying that Dinosaurs, (so it is said) evolved in to birds becouse, they needed to adapt, to the changed conditions after the astroiod hit the earth?.

However as I have always understood Darwin , evolution takes millions of years, so if the earth was no longer inhabitable , for some spicies, why did they not just die out?.

If for an example the earth today was flooded, would it not take millions of years for us to grow finns?, "How would we surrvive in the meantime?.

Answer 1

That is a good question. I don't think they did.

First of all, bird evolution is one of the most controversial areas in evolutionary paleontology and evolutionists often disagree and criticize each other.

We hear a lot of reports of feathered dinosaurs being found, but what you rarely hear, is that the main candidates are believed by many experts to simply be frayed collagen fibers, or hair like structures that could have supported a frill or crest like those on iguanas, or are on animals that are not dinosaurs, but flightless birds. The drawings are certainly not what we find; they are just the artists’ imagination. Dr. Alan Feduccia, a world authority on birds and an evolutionist, along with his coworkers have presented a substantial body of evidence to support their view that there are, in fact, no known dinosaurs with feathers (they believe birds evolved from different reptiles, but not dinosaurs).

And then you have ones like Archaeoraptor that was proven to be a hoax. Who knows how many times that will happen.

All these announcements of feathered dinosaurs cause a lot of media fanfare, but when they are refuted, there is scarcely a whimper in the media.

You may be thinking, “But what about Archaeopteryx? That has been used for years and years.” Archaeopteryx was a true perching bird with fully formed wings and flight feathers, as well as a large wishbone for the attachment of muscles used for the downstroke of the wings.

So what is all the fuss about; why is Archaeopteryx such an icon of dinosaur to bird evolution? Well, it had teeth in the bill, claws on the wings, no keel on the breast bone, an unfused backbone, and a long, bony tail, which are all characteristics most people associate with reptiles.

But as Dr. Gary Parker said, “...the reptile-like features are not really as reptile-like as you might suppose. The familiar ostrich, for example, has claws on its wings that are even more ‘reptile-like’ than those of Archaeopteryx. Several birds, such as the hoatzin, don’t have much of a keel. The penguin has unfused backbones and a bony tail. No living birds have socketed teeth, but some fossil birds do. Besides, some reptiles have teeth and some don’t, so the presence or absence of teeth is not particularly important in distinguishing the two groups.”

Dr. Alan Feduccia (like I said, an evolutionist, and by the way, one who doesn’t like creationists like me quoting him) said, “Paleontologists have tried to turn Archaeopteryx into an earth-bound, feathered dinosaur. But it’s not. It is a bird, a perching bird. And no amount of ‘paleobabble’ is going to change that.”

On top of that, scientists have found fossils of what they would call “true birds” in layers of rock that they date as being older than Archaeopteryx. That presents a problem for them.

I believe Archaeopteryx was something of a mosaic like a bat or platypus. Similar structures simply point to a common designer. God knew what designs would work well in multiple animals.

What they need to find, is a fossil showing scales turning into feathers, or a leg turning into a wing, or the reptile lung turning into the avian lung. How you can take a “two-way” reptile lung and evolve it into a fully functional “one-way” bird lung without causing extinction of the species is quite a conundrum.

There is no credible evidence that dinosaurs evolved into birds. Dinosaurs have always been dinosaurs and birds have always been birds.

Answer 2

The other answers you have received are excellent. Let me point out some general things about evolution which might help you with the big picture. Remember that no specific, individual creature evolves from a dinosaur to a bird. Evolution just says that many organisms have common ancestors. If the dinos had not become extinct, there would be dinos and birds today. The birds did not evolve BECAUSE of the changing conditions, although change does affect the direction evolution takes. (It's better to think of evolution taking many different directions, but most of them being unsuccessful.)
If the earth today was flooded, humans might go extinct. Or we might survive with our ingenuity, making floating islands. Who knows? That doesn't mean we would grow fins. Certainly, some people that are fast swimmers might live longer and have more babies. Some people with large fleshy hands might be able to swim faster, fewer get eaten by sharks, more live to reproduce, so more and more babies are born with fleshy hands.
I'm simplifying, but do you see the point? Change is happening slowly, not in order to solve some great problem that nature poses. Evolution does not happen to fulfill a goal. It just happens.
The best part of your question, though, is about why so many of the lines of dinosaurs that didn't lead to birds died out, but why the ones that did lead to birds made it. Why don't you consider what the advantages might be of being warm-blooded or having feathers. Both of these conditions had evolved before the asteroid.

Answer 3

Not all dinosaurs evolved into birds, just a very few lineages. Also, they didn't evolve in response to the extinction event, they had been evolving long before that.

There are several theories as to why certain lineages made the leap from dinosaur to bird, look up bottom up vs. top down theory. Feathers were probably initially used for warmth, and it is usually hypothesized that they offered a competitive advantage either by giving lift to running, jumping dinosaurs (perhaps allowing them to catch flying insects) or by giving lift to running, jumping dinosaurs (perhaps allowing them not to be chomped to death by bigger dinosaurs). It did take a very long time, but the evolution is very well documented in the fossil record.

Answer 4

Birds first appear in the fossil record about 140 million years ago, approximately 75 million years before the extinction of the dinosaurs and before the asteroid that, in theory, lead to their extinction. It did take many millions of years for birds to evolve from their dinosaur ancestor.

Answer 5

14o million years ago, birds first appeared but it takes millions of years to evolve from stiff arms to flexible wrist of Velociraptor, to flapping arms of Unenlagia to Primitive birdlike caudipteryx, then towards Protarchaeopteryx to Archaeopteryx, millions of years later, Eoalulavis appeared then to birds. It is very complex to tell you whole