Dinosaur feather evolution trapped in Canadian amber

[klr]

"Dinosaurs and birds"? that's an odd phrase. It's a bit like "planets and Saturn" or "hot drinks and tea" or "tosspots and Piers Morgan". - The later is included in the former.

Only in a certain sense. Most biologists don't consider birds to be dinosaurs even if they are directly descended from them. It is easy to think of them as dinos that can fly, but they do differ in other specific ways too.

Though, I do like referring to them as dinosaurs myself too.

You may as well say the same about "fish and mammals" then, since mammals (and all tetrapods) are descended from fish, and are closer to bony fish than the latter are to cartilaginous fish.

[Pappa]

Evolution is a LIE put forth by all those Godless Atheists (may they burn in the hell they so richly deserve) just so they go around having sex without feeling guilt which is God's gift to us so we wont enjoy this world too much.

Btw Jay G, I wish you'd spend more time here.

[Horwood Beer-Master]

"Dinosaurs and birds"? that's an odd phrase. It's a bit like "planets and Saturn" or "hot drinks and tea" or "tosspots and Piers Morgan". - The later is included in the former.

Only in a certain sense. Most biologists don't consider birds to be dinosaurs even if they are directly descended from them. It is easy to think of them as dinos that can fly, but they do differ in other specific ways too.

Though, I do like referring to them as dinosaurs myself too.

You may as well say the same about "fish and mammals" then, since mammals (and all tetrapods) are descended from fish, and are closer to bony fish than the latter are to cartilaginous fish.

It could be argued that the word "fish" like the word "reptile" is no longer a taxonomically useful term and ought therefore to be abandoned.

Tetrapods, including mammals, should simply be regarded as sarcopterygians instead.

[Gawdzilla Sama]

"Yer grandpa was a slime mold!"

[Horwood Beer-Master]

"Yer grandpa was a slime mold!"

No. The Mycetozoa Slime Molds belong to the Amoebozoa, and are thus cousins of animals, fungi and related groups.

Other organisms that are sometimes termed "slime molds" either also belong to the Amoebozoa or to even more distantly related groups, possibly closer to plants than to us.


Either way, the term describes more a general lifestyle rather than a proper grouping of organisms, and there is no evidence I'm aware of that any organism ancestral to us would have behaved in a 'slime mold' fashion (although I suppose it can't be ruled-out).
But even if it did, it wouldn't have belonged to any group of organisms today that go under that name, and certainly not to the Mycetozoa - the group to which it is most commonly applied.

[Jay G]

Evolution is a LIE put forth by all those Godless Atheists (may they burn in the hell they so richly deserve) just so they go around having sex without feeling guilt which is God's gift to us so we wont enjoy this world too much.

Btw Jay G, I wish you'd spend more time here.

Thank you. I asked God if it's OK and he said yes.

[GenesForLife]

Samples of amber in western Canada containing feathers from dinosaurs and birds have yielded the most complete story of feather evolution ever seen...

"Dinosaurs and birds"? that's an odd phrase. It's a bit like "planets and Saturn" or "hot drinks and tea" or "tosspots and Piers Morgan". - The later is included in the former.

"Dinosaurs" here would just mean non-avian ones. Of course, dinosaurs defined according to cladistics (which birds are) are different from dinosaurs defined taxonomically (where birds are an altogether different class of vertebrates)

[Svartalf]

I never got the "birds are dinosaurs" thing as, last I checked, dinosaurs were still reptiles, which birds are not...
do we even have warm blooded reptiles around?

[Hermit]

I never got the "birds are dinosaurs" thing as, last I checked, dinosaurs were still reptiles, which birds are not...
do we even have warm blooded reptiles around?

Yes. They are more commonly known as birds, though, which neatly brings us around to the conclusion that we can justifiably differentiate dinosaurs from birds.

[GenesForLife]

I never got the "birds are dinosaurs" thing as, last I checked, dinosaurs were still reptiles, which birds are not...
do we even have warm blooded reptiles around?

Yes. They are more commonly known as birds, though, which neatly brings us around to the conclusion that we can justifiably differentiate dinosaurs from birds.

Only taxonomically!

Cladistically speaking, new clades are nested within ancestral clades, and are therefore a part of those ancestral clades. I.e, birds and mammals and reptiles all belong to the same clade if you go back in time, i.e, we are all whatever term is applied to that clade. Go further back, include amphibians, and we begin to belong to the same clade as bony fish. Further back, same clade as all Eukaryotes, further back, same clade as all life.

We are, consequently, replicators, eukaryotes, multicellular, vertebrates, tetrapods and so on...

PS - A clade is defined as a species + all its descendents. Due to this, if X descended from Y and Y descended from Z, X is still a descendent of Z and therefore belongs to the same clade.

[Gawdzilla Sama]

"Yer grandpa was a slime mold!"

No. The Mycetozoa Slime Molds belong to the Amoebozoa, and are thus cousins of animals, fungi and related groups.

Other organisms that are sometimes termed "slime molds" either also belong to the Amoebozoa or to even more distantly related groups, possibly closer to plants than to us.


Either way, the term describes more a general lifestyle rather than a proper grouping of organisms, and there is no evidence I'm aware of that any organism ancestral to us would have behaved in a 'slime mold' fashion (although I suppose it can't be ruled-out).
But even if it did, it wouldn't have belonged to any group of organisms today that go under that name, and certainly not to the Mycetozoa - the group to which it is most commonly applied.

[Hermit]

I never got the "birds are dinosaurs" thing as, last I checked, dinosaurs were still reptiles, which birds are not...
do we even have warm blooded reptiles around?

Yes. They are more commonly known as birds, though, which neatly brings us around to the conclusion that we can justifiably differentiate dinosaurs from birds.

Only taxonomically!

Thanks for expanding on what Horwood Beer-Master alluded to earlier. While cladistics is undoubtedly scientifically more thoroughgoing, I think for the purposes of this discussion the Linnæan mode of classification is quite appropriate. It may actually be more appropriate here, seeing cladistically birds are not only descendant from reptiles, but also amphibians, fish, insects and so on, while there is a reasonably clear distinction between what typifies reptiles on one end of the scale and birds on the other from a taxonomic point of view, even though there inevitably is a fair amount of feathering at the transition between the two.

[Horwood Beer-Master]

Samples of amber in western Canada containing feathers from dinosaurs and birds have yielded the most complete story of feather evolution ever seen...

"Dinosaurs and birds"? that's an odd phrase. It's a bit like "planets and Saturn" or "hot drinks and tea" or "tosspots and Piers Morgan". - The later is included in the former.

"Dinosaurs" here would just mean non-avian ones. Of course, dinosaurs defined according to cladistics (which birds are) are different from dinosaurs defined taxonomically (where birds are an altogether different class of vertebrates)

But isn't "class" in this sense (well in others too), just an arbitrary old Victorian hang-over? Even a pre-Darwinian hang-over if you think about it (though that could be said for the whole Linnæan system really - I'm sure Prof Dawkins would have some stuff to say about "discontinuous minds" at this point...)

I never got the "birds are dinosaurs" thing as, last I checked, dinosaurs were still reptiles, which birds are not...
do we even have warm blooded reptiles around?

To the last point - yes - in the sense that there are animals we call reptiles that can maintain a higher body temperature independent of their environment - leatherback turtles for instance. And for that matter there are mammals (like sloths) whose body temperature is very ('though not entirely) dependant on the outside temperature, and birds (hummingbirds) that can enter a state of torpor, allowing their bodies to cool right down.

As for the word reptile itself, it again is a bit arbitrary really.

...birds and mammals and reptiles all belong to the same clade if you go back in time, i.e, we are all whatever term is applied to that clade...

Amniotes.