Talk:Coelurosauria
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[edit] Feathered Dinosaurs
There is not one undisputed "feathered dinosaur", much less any evidence to support the idea that feathers might characterize any significant portion of this Order. A parsimonious hypothesis is a careful, conservative option, not the most outlandish! Mdotley 13:15, 12 September 2006 (UTC)
- Followup: The Reference given for the statement that all coelurosaurs probably had feathers actually says otherwise. Some of the examples cited may well be "secondarily flightless birds", which would necessitate an even LONGER evolutionary history, as flight would have to have evolved and then been lost. Mdotley 16:17, 14 September 2006 (UTC)
- A minority of paleoornithologists, mainly Feduccia and Martin (though Martin has backed down a bit in recent years), holds that birds and dinosaurs are unrelated. They believe protofeathers represent frayed collagen, though subsequent papers have demonstrated this to be false. The unabiguously feahtered dinosaurs, like dromaeosaurids, troodontids, oviraptorosaurs, etc, they believe to be non-dinosaurian. This is an exreme minority position, and is discussed at length (or should be) at Feathered dinosaurs. It doesn't need to be re-iterated on every one of the dozens of articles discussing a particular group of "dinosaurs" for which feathers are known.Dinoguy2 19:23, 14 September 2006 (UTC)
- How do you know that "all coelurosaurians had feathers"? What fossils show this? Were they from China, by any chance? Ratso 22:49, 20 March 2007 (UTC)
Not all coelurosaurians had fethers; rex didn't. 122.109.250.74 (talk) 08:37, 5 May 2008 (UTC)
- Neither did Juravenator. Feathers arose within coelurosaurs, so the primitive ones were still mostly scaly, or only partially feathered. Dinoguy2 (talk) 09:25, 5 May 2008 (UTC)
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- I agree that "there is not one undisputed feathered dinosaur, much less any evidence to support the idea that feathers might characterize any significant portion of this Order". In addition, there are coelurosaur fossils other than T Rex that didn't have feathers. In particular, the timing of fossil feathers is all wrong for Aves to have been deep within the coelurosaur taxonomy as shown in the phylogeny. If present at all, the Aves would have been an early split perhaps on the same level as the tyrannosauridae, as suggested in the taxonomy on Entrez/genbank. Mollwollfumble (talk) 02:36, 28 May 2008 (UTC)
- You're reading the cladogram wrong. It doesn't reflect time, it reflects order of divergance. For example, if some highly specialized lineage of giant carnivorous platypus evolved from monotremes, it would still be near the base of the cladogram compared to say, mice. The fact is that very bird-like maniraptoran dinosaurs lived alongside or predate Archaeopteryx, if you count Archie as a bird (the difference between Archie and a troodontid is pretty subtle and negligible anyway). Pedopenna and Epidendrosaurus, for example, pre-date the first "bird", and advanced birds don't start showing up in the fossil record until the early Cretaceous anyway, same time as many known feathered dinosaurs. The tyrannosaur lineage split off from other coelurosaurs at least in the Middle Jurassic, I don't see why it's so hard to recognize that it was only after this divergence that feathers appeared in one of the other coelurosaur lineages (the one leading to maniraptorans, Sinosauropteryx, Sinocalliopteryx, Dilong, etc. The big problem that leads to confusion is that small theropods from the early-mid Jurassic are almost completely unknown, period. We know they were there, we have scraps and teeth, but very few fossils, let alone skin impressions. It looks like all the main maniraptoran lineages MUST have existed by the mid-Jurassic. Birds probably split off during this time, tyrannosaurs a fair bit earlier. We just don't have any fossils from that time at all. Dinoguy2 (talk) 03:30, 28 May 2008 (UTC)
- You're right, Dinoguy2, I've done a bit more reading now and that confirms what you say. However, the cladograms I've found in the literature, one from 2001 and two from 2005, disagree significantly with the Wiki one from 2004. The two from 2005 are almost in perfect agreement with one another, differing only in whether the tyrannosauroidae are included in the maniraptoriformes. The one from 2001 is different to both the 2004 and 2005 ones but has the advantage of listing approximate fossil dates. The cladogram that I'd be most likely to trust is from Nature 437, 1007-1011 (13 Oct 2005). From this and other cladograms, Proceratosaurus is not in the Coelurosauria, for example, and Ornitholestes and Compsognathidae are both within the Maniraptoriformes. Mollwollfumble (talk) 12:02, 28 May 2008 (UTC)
- Senter(2007) "Journal of Systematic Paleontology" contains an even better cladogram. Mollwollfumble (talk) 01:19, 29 May 2008 (UTC)
- Senter 2007 is very good, and parts of it are included in some other articles around here. But Dinosauria II is a very well respected and comprehensive source, which makes it a good candidate to use for stability's sake. The cladogram for Coelurosauria will inevitably change with each study, might as well go with a big gun until more information stabilizes the thing as a whole. Senter 2007 also includes some odd bits, like having Sinraptor as a coelurosaur, mainly because basal forms were not the focus of the study. Dinoguy2 (talk) 02:38, 29 May 2008 (UTC)
- Have updated the cladogram. Hope you like it. Senter doesn't have Sinraptor as a coelurosaur, he has it as one of the two outgroups, the other being Allosaurus. Mollwollfumble (talk) 11:38, 30 May 2008 (UTC)
- That cladogram is intricate. It took me a while to figure out that Oviraptorosauria and Paraves weren't coming off of Ornithomimus, so perhaps a couple of extra non-breaking spaces in front of the second cladogram are in order? I'd also de-link IGM 100/44 and the other red-linked undescribed specimens. Firsfron of Ronchester 21:06, 30 May 2008 (UTC)
- Done. Mollwollfumble (talk) 21:44, 2 June 2008 (UTC)
- That cladogram is intricate. It took me a while to figure out that Oviraptorosauria and Paraves weren't coming off of Ornithomimus, so perhaps a couple of extra non-breaking spaces in front of the second cladogram are in order? I'd also de-link IGM 100/44 and the other red-linked undescribed specimens. Firsfron of Ronchester 21:06, 30 May 2008 (UTC)
- Have updated the cladogram. Hope you like it. Senter doesn't have Sinraptor as a coelurosaur, he has it as one of the two outgroups, the other being Allosaurus. Mollwollfumble (talk) 11:38, 30 May 2008 (UTC)
- Senter 2007 is very good, and parts of it are included in some other articles around here. But Dinosauria II is a very well respected and comprehensive source, which makes it a good candidate to use for stability's sake. The cladogram for Coelurosauria will inevitably change with each study, might as well go with a big gun until more information stabilizes the thing as a whole. Senter 2007 also includes some odd bits, like having Sinraptor as a coelurosaur, mainly because basal forms were not the focus of the study. Dinoguy2 (talk) 02:38, 29 May 2008 (UTC)
- Senter(2007) "Journal of Systematic Paleontology" contains an even better cladogram. Mollwollfumble (talk) 01:19, 29 May 2008 (UTC)
- You're right, Dinoguy2, I've done a bit more reading now and that confirms what you say. However, the cladograms I've found in the literature, one from 2001 and two from 2005, disagree significantly with the Wiki one from 2004. The two from 2005 are almost in perfect agreement with one another, differing only in whether the tyrannosauroidae are included in the maniraptoriformes. The one from 2001 is different to both the 2004 and 2005 ones but has the advantage of listing approximate fossil dates. The cladogram that I'd be most likely to trust is from Nature 437, 1007-1011 (13 Oct 2005). From this and other cladograms, Proceratosaurus is not in the Coelurosauria, for example, and Ornitholestes and Compsognathidae are both within the Maniraptoriformes. Mollwollfumble (talk) 12:02, 28 May 2008 (UTC)
- You're reading the cladogram wrong. It doesn't reflect time, it reflects order of divergance. For example, if some highly specialized lineage of giant carnivorous platypus evolved from monotremes, it would still be near the base of the cladogram compared to say, mice. The fact is that very bird-like maniraptoran dinosaurs lived alongside or predate Archaeopteryx, if you count Archie as a bird (the difference between Archie and a troodontid is pretty subtle and negligible anyway). Pedopenna and Epidendrosaurus, for example, pre-date the first "bird", and advanced birds don't start showing up in the fossil record until the early Cretaceous anyway, same time as many known feathered dinosaurs. The tyrannosaur lineage split off from other coelurosaurs at least in the Middle Jurassic, I don't see why it's so hard to recognize that it was only after this divergence that feathers appeared in one of the other coelurosaur lineages (the one leading to maniraptorans, Sinosauropteryx, Sinocalliopteryx, Dilong, etc. The big problem that leads to confusion is that small theropods from the early-mid Jurassic are almost completely unknown, period. We know they were there, we have scraps and teeth, but very few fossils, let alone skin impressions. It looks like all the main maniraptoran lineages MUST have existed by the mid-Jurassic. Birds probably split off during this time, tyrannosaurs a fair bit earlier. We just don't have any fossils from that time at all. Dinoguy2 (talk) 03:30, 28 May 2008 (UTC)
- I agree that "there is not one undisputed feathered dinosaur, much less any evidence to support the idea that feathers might characterize any significant portion of this Order". In addition, there are coelurosaur fossils other than T Rex that didn't have feathers. In particular, the timing of fossil feathers is all wrong for Aves to have been deep within the coelurosaur taxonomy as shown in the phylogeny. If present at all, the Aves would have been an early split perhaps on the same level as the tyrannosauridae, as suggested in the taxonomy on Entrez/genbank. Mollwollfumble (talk) 02:36, 28 May 2008 (UTC)
Yikes, can we simplify this cladogram a little? I feel like it's a bit inaccessible for me, let alone the average reader. We don't have to include everything down to genus level here, a cladogram showing the relationships of major groups should be fine. Dinoguy2 (talk) 04:57, 1 June 2008 (UTC)
- A little, yes we certainly can, but not that much, please. What I most disliked about my version was the large amount of vertical space between rows, which made the whole thing much higher than it needed to be and consequently more difficult to understand. The whole cladogram should fit on one page (at good monitor resolution). I think the system of using numbers to index cladistic groups worked surprising well. I'm OK with the switch back from Coelurus_BW.jpg to Coelurus.jpg, but isn't the BW one more recent? The discussion on it is dated 13 May 2008. We both agree that the picture on "Approved dinosaur images" of "Coelurus picture2.png" is inferior.Mollwollfumble (talk) 09:53, 1 June 2008 (UTC)
- Can we get a compromise between the cladogram versions? Moll's was nice because it did show various genera and the family levels. I get the feeling Dinoguy's version is so abbreviated that readers would miss out on a lot. Firsfron of Ronchester 11:43, 1 June 2008 (UTC)
- What about having both in the article? The more complex/indepth cladogram could be in a show/hide box? Steveoc 86 (talk) 17:30, 1 June 2008 (UTC)
- I tried and failed to make an alternative clade template, so put back a severely pruned version of the cladogram. Perhaps I pruned it too much, Eotyrannus is mentioned in the text so should be on the cladogram.Mollwollfumble (talk) 21:44, 2 June 2008 (UTC)
- My main problems with the long cladogram is that it's split into two, which is confusing, and that you need to refer to a key to get the clade names, where most if not all of our other cladograms are labeled directly. Even in two columns, the whole thing doesn't fit on one screen, and I have to scroll up and down to see the numbers and the names that go with them... bit of a hassle. I would even argue that we already have a show/hide box of sorts, as each of the sub-clades do (or should) have their own, even more in-depth cladograms. Clicking on Therizinosauroidea brings you to a page with a cladogram from Senter 2007 and includes most therizinosaur genera. Dinoguy2 (talk) 21:50, 2 June 2008 (UTC)
- My main problem with it is that it doesn't explicitly mention modern birds, the average wikipedia user may not know that Ornithurae means birds. The clade template has a bug in the sideways spacing which means that it mucks up when long clade names are added. Using numbers isn't ideal but fixes the problem. It also acts to remind readers that clades are somewhat arbitrary and are not always well defined. I think it's a pity that bootstrap values can't be added as well, they give a clear indication as to how reliable each part of the cladogram is. Mollwollfumble (talk) 10:01, 3 June 2008 (UTC)
- I think adding bootstrap values would definitely be going too far. My philosophy has always been to write with a high school-level audience in mind. Anybody who would advanced enough have need for bootstrap values would also presumably have access to the original paper and would not need to read the Wikipedia article (or they'd be looking at EvoWiki, which is way more technical than Wikipedia). A majority of the people reading this are not going to know what a clade is before coming here, and we want to make sure we're not complicating things so much that the intricacies of cladistics need to be explained in every article. Dinoguy2 (talk) 13:50, 3 June 2008 (UTC)
- This looks like a good application for an idea I posted at the Village Pump in Nov 2007. Many UIs feature expanding / collapsing hierarchies (e.g. mail folders in email clients, folders in Windows Explorer, menus on some web sites). Technically it's quite easy to do in a normal Web page: the HTML is nested ULs; the CSS defines styles for nodes (folders, stem clades, etc.); a Javascript expands / collapses nodes when you click on them. From my point of view the tricky bit is doing this in the Wikipedia framework, as I'm a lot less familiar with that than I am with HTML+CSS+Javascript. But I notice Wikipedia's littered with "hide/show" links, especially on Talk pages and some Wikiproject pages. Perhaps we can exploit the "hide/show" scripts to produce expanding / collapsing hierarchies for big cladograms. Philcha (talk) 11:09, 3 June 2008 (UTC)
- My main problem with it is that it doesn't explicitly mention modern birds, the average wikipedia user may not know that Ornithurae means birds. The clade template has a bug in the sideways spacing which means that it mucks up when long clade names are added. Using numbers isn't ideal but fixes the problem. It also acts to remind readers that clades are somewhat arbitrary and are not always well defined. I think it's a pity that bootstrap values can't be added as well, they give a clear indication as to how reliable each part of the cladogram is. Mollwollfumble (talk) 10:01, 3 June 2008 (UTC)
- My main problems with the long cladogram is that it's split into two, which is confusing, and that you need to refer to a key to get the clade names, where most if not all of our other cladograms are labeled directly. Even in two columns, the whole thing doesn't fit on one screen, and I have to scroll up and down to see the numbers and the names that go with them... bit of a hassle. I would even argue that we already have a show/hide box of sorts, as each of the sub-clades do (or should) have their own, even more in-depth cladograms. Clicking on Therizinosauroidea brings you to a page with a cladogram from Senter 2007 and includes most therizinosaur genera. Dinoguy2 (talk) 21:50, 2 June 2008 (UTC)
- I tried and failed to make an alternative clade template, so put back a severely pruned version of the cladogram. Perhaps I pruned it too much, Eotyrannus is mentioned in the text so should be on the cladogram.Mollwollfumble (talk) 21:44, 2 June 2008 (UTC)
- What about having both in the article? The more complex/indepth cladogram could be in a show/hide box? Steveoc 86 (talk) 17:30, 1 June 2008 (UTC)
- Can we get a compromise between the cladogram versions? Moll's was nice because it did show various genera and the family levels. I get the feeling Dinoguy's version is so abbreviated that readers would miss out on a lot. Firsfron of Ronchester 11:43, 1 June 2008 (UTC)
[edit] Rex's thigh was longer than its calf
but this article says that coelurosaurs had longer calfs than thighs! 122.109.250.74 (talk) 08:34, 5 May 2008 (UTC)
[edit] Still need to add
Dates of early fossils, origins probably in the mid Jurassic, relatively short time needed for diversification, survival into the Cretaceous. Mollwollfumble (talk) 11:38, 30 May 2008 (UTC)
- OK, done that. That's about all I want to add, apart from putting back some references that I accidentally deleted, and possibly adding one or two more.Mollwollfumble (talk) 18:51, 30 May 2008 (UTC)
- Want to add a reference to the avian feather keratin found on Shuvuuia, and the protofeathers on Dilong in the "feathered dinosaur" section, the last is important because Dilong is so similar to the ancestral Coelurosaurs.Mollwollfumble (talk) 12:11, 2 June 2008 (UTC)
