Real Science Friday: An Extinct Bird - Archaeopteryx

[One Eyed Jack]

Well, here's what he actually says about Archaeopteryx:

Alate_One says his views are untestable and therefore not science. Who am I to believe?

 

[Alate_One]

Who cares? I'm not an evolutionist.

But both you and Bob are pretending that Archeopteryx being a bird somehow causes a problem for evolution. It doesn't.

Feduccia says it's a full-fledged bird.

See what Flipper just said. A transitional organism isn't something that defies classification it is simply something that has ancestral as well as derived (more evolved) traits. Archeopteryx retains a lot of ancestral characters and has a number of derived ones.

 

[Alate_One]

Alate_One says his views are untestable and therefore not science. Who am I to believe?

Learn to read what I'm actually saying please. Bird or dinosaur is simply classification. What is untestable about Alan Feduccia's views is he asserts that there are unknown reptilian ancestors that evolved into birds. Since they haven't been found (and may not exist) we can't test them against the theropod hypothesis. So his view of bird evolution is untestable until he can point to actual fossils he thinks are ancestors.

 

[One Eyed Jack]

But both you and Bob are pretending that Archeopteryx being a bird somehow causes a problem for evolution. It doesn't.

It seems to be a problem for the dinosaur to bird hypothesis.

 

[One Eyed Jack]

Learn to read what I'm actually saying please.

I did read what you said.

Bird or dinosaur is simply classification. What is untestable about Alan Feduccia's views is he asserts that there are unknown reptilian ancestors that evolved into birds.

Right -- and you said this isn't science. Now, I didn't think you really wanted to go there, but liberals like yourself are notorious for being short-sighted.

Since they haven't been found (and may not exist) we can't test them against the theropod hypothesis. So his view of bird evolution is untestable until he can point to actual fossils he thinks are ancestors.

So I guess your view on the origin of human beings is untestable (and therefore unscientific) until you can find a fossil that you think is an actual human ancestor rather than a side-branch.

 

[Ktoyou]

Birds are dinosaurs.

Birds are birds and "The birds" was Hitchcock, here is the dinosaur.

Barney is a dinosaur

 

[One Eyed Jack]

I remember a cartoon in Dragon magazine years ago in which a knight had slain Barney. There were kids crying, and the knight was looking all sheepish, saying it was dark, and it could have been a dragon for all he knew.

Hey, I found a copy online -- Dragon #200. Page 151, under Dragon Mirth. And this copy isn't damaged... I'm gonna have to redownload some of these.

 

[Alate_One]

So I guess your view on the origin of human beings is untestable (and therefore unscientific) until you can find a fossil that you think is an actual human ancestor rather than a side-branch.

No, you misunderstood what I was saying. Feduccia says that there are reptilian *groups* INSTEAD of theropods that are ancestral to birds but they are cryptic and we don't have fossils of them. He says that theropods aren't ancestral to birds and their similarities represent convergent evolution. You can't do cladistics analysis on fossils to determine if his hypothesis is correct without having fossils of those organisms he says are the *real* ancestral groups.

I am not saying the individual organisms in the fossils themselves must be ancestral to anything since you can't know that, you can only determine that they have a high likelihood of being related and approximately how closely related.

 

[One Eyed Jack]

No, you misunderstood what I was saying.

I don't think so. You said "So his view of bird evolution is untestable until he can point to actual fossils he thinks are ancestors."

What's good for the goose is good for the gander. If his views concerning bird evolution are untestable (and therefore unscientific), then so are your views concerning human evolution. Unless you can come up with a fossil that you believe is a direct human ancestor. Do you have one?

Feduccia says that there are reptilian *groups* INSTEAD of theropods that are ancestral to birds but they are cryptic and we don't have fossils of them.

I understand that. He thinks it's some kind of archosaur we haven't found yet.

He says that theropods aren't ancestral to birds and their similarities represent convergent evolution. You can't do cladistics analysis on fossils to determine if his hypothesis is correct without having fossils of those organisms he says are the *real* ancestral groups.

I don't think he's a cladist, anyway.

I am not saying the individual organisms in the fossils themselves must be ancestral to anything since you can't know that

I know you're not saying that. I'm cool with pretty much any representative of the species in question. Just give me something more than a couple of teeth, okay?

 

[Stripe]

And when you do find more fossils, make sure and carefully describe their in situ environment. Both micro and macro. :thumb:

Then I will quickly be able to show you how everything you find in that area was all deposited at the same time.

 

[Alate_One]

I don't think so. You said "So his view of bird evolution is untestable until he can point to actual fossils he thinks are ancestors."

What's good for the goose is good for the gander. If his views concerning bird evolution are untestable (and therefore unscientific), then so are your views concerning human evolution. Unless you can come up with a fossil that you believe is a direct human ancestor. Do you have one?

The Denisovans may have contributed to at least some modern humans as have Neanderthals. We can tell that because there's actually DNA left, which is far better than just bones.

I know you're not saying that. I'm cool with any pretty much any representative of the species in question. Just give me something more than a couple of teeth, okay?

I'm not talking species, I'm talking groups of organisms. The fossils in question may be offshoots but represent a group that was ancestral. It's hard to know what is a species when looking at fossils anyway.

 

[One Eyed Jack]

The Denisovans may have contributed to at least some modern humans as have Neanderthals.

I've known some modern humans who could pass for Neanderthals.

We can tell that because there's actually DNA left, which is far better than just bones.

I don't have any particular beef with that, as I think they were human anyway.

I'm not talking species, I'm talking groups of organisms. The fossils in question may be offshoots but represent a group that was ancestral.

Then what's wrong with Feduccia's archosaurs? I've seen a couple that weren't dinosaurs, but were quite theropod-like (Shuvosaurus, for example). They could be offshoots that represent the group from which birds sprang.

It's hard to know what is a species when looking at fossils anyway.

I wouldn't argue with that.

 

[Alate_One]

Then what's wrong with Feduccia's archosaurs? I've seen a couple that weren't dinosaurs, but were quite theropod-like (Shuvosaurus, for example). They could be offshoots that represent the group from which birds sprang.

They could be, but you're missing everything in between (Shuvorsaurus is from back in the triassic) and we have the feathered dinosaurs that have been found. So either feathers evolved early and were lost in some lineages and magically appeared in some dinosaur lineages through convergent evolution (meaning flight feathers evolved twice) or all the feathered dinosaurs are actually flightless birds. Any of those possibilities are less parsimonious than simply linking dinosaurs to birds. And in making evolutionary hypotheses, maximum parsimony is preferred.

These are all *possible* but with our currently available materials we can't test them very well since we can't tell convergent evolution if there's nothing else to compare that the organism is converging on. Until there is strong evidence to contradict it, the Theropod hypothesis for the origin of birds is a good one. And as we are getting more data a lot of the problems are getting cleared up and MORE problems are being created for Feduccia's ideas.

 

[Paulos]

Alan Feduccia is an ornithologist, and he's says it's a bird. What are you?

Apparently, you are quoting Feduccia out of context. In an attempt to clarify his view, he stated:

"Archaeopteryx is clearly transitory between reptiles and birds..."

Source: http://aigbusted.synthasite.com/Archaeopteryx.php

 

[One Eyed Jack]

Apparently, you are quoting Feduccia out of context.

I'm not quoting him out of context at all, nor have I ever said or implied that he didn't believe birds evolved from reptiles.

 

[One Eyed Jack]

They could be, but you're missing everything in between (Shuvorsaurus is from back in the triassic) and we have the feathered dinosaurs that have been found. So either feathers evolved early and were lost in some lineages and magically appeared in some dinosaur lineages through convergent evolution (meaning flight feathers evolved twice) or all the feathered dinosaurs are actually flightless birds.

Well, I think some of these so-called feathered dinosaurs are birds, and some are dinosaurs and didn't really have feathers. I'm sure you're familiar with the whole proto-feather debate.

Any of those possibilities are less parsimonious than simply linking dinosaurs to birds. And in making evolutionary hypotheses, maximum parsimony is preferred.

These are all *possible* but with our currently available materials we can't test them very well since we can't tell convergent evolution if there's nothing else to compare that the organism is converging on. Until there is strong evidence to contradict it, the Theropod hypothesis for the origin of birds is a good one. And as we are getting more data a lot of the problems are getting cleared up and MORE problems are being created for Feduccia's ideas.

As a creationist, I'm not so much defending Feduccia's ideas as letting you know that I'm aware of them. I have my own, as I'm sure you know.