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Post by neovenator08 on Apr 2, 2011 7:28:20 GMT
Forgive me for being a little behind here (  ) but when I was younger all the dinosaur books had Anatosaurus in them. Now I hear Anatotitan. Are these different dinosaurs? Did it suddenly come into fashion to name all hadrosaurs ____titan (as in Olorotitan)? Because personally I think it's an awful name. |
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Post by dinoguy2 on Apr 2, 2011 11:20:31 GMT
There's a good explanation here: en.wikipedia.org/wiki/Edmontosaurus#Anatosaurus_to_the_presentThe short version: Some scientists decided that the Anatosaurus specimens which carried that name actually belonged to a species of Edmontosaurus. However, some specimens previously thought to be Anatosaurus did not belong o Edmontosaurus, so those needed a new name, which they called Anatotitan. I should note that not everybody agrees with this. There is new research in the works that shows the original idea may gave been right, and that Edmontosaurus annectens (=Anatosaurus) is the same thing as Anatotitan. Similar to the Toroceratops hypothesis, the flat, famous duck-like bill and giant size that marks Anatotitan might have developed late in life. If that's true, then Anatosaurus annectens might be a valid name for this genus. Alternately, since this would also mean there was only one species of hadrosaur in the Hell Creek formation, the right name might well be Trachodon after all (it's the oldest name for any duckbill remains in that time period). |
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Post by neovenator08 on Apr 2, 2011 12:39:36 GMT
OK, so some Anatosaurus remains were Edmontosaurus, and some weren't. So the ones that weren't were named Anatotitan instead, right?
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Post by dinoguy2 on Apr 2, 2011 18:12:31 GMT
OK, so some Anatosaurus remains were Edmontosaurus, and some weren't. So the ones that weren't were named Anatotitan instead, right? Correct. |
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Post by neovenator08 on Apr 2, 2011 19:06:44 GMT
But how come they named the Anatosaurus remains that weren't Edmontosaurus a new name rather than just sticking with Anatosaurus? In my opinion it sounds much better.
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Post by Horridus on Apr 2, 2011 19:07:12 GMT
But how come they named the Anatosaurus remains that weren't Edmontosaurus a new name rather than just sticking with Anatosaurus? In my opinion it sounds much better. ICZN rules... |
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Post by Griffin on Apr 2, 2011 19:09:32 GMT
Did some edmontosaurus and anato...thingies live during different time periods though? If I'm not mistaken I thought edmontos lived a bit earlier, then they overlapped for a bit and anato...sourotitanwhateverthehecks lived during the tail end? This is off the top of my head without reference correct me if I'm wrong here.
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Post by Horridus on Apr 2, 2011 19:11:23 GMT
I'm quite sure Edmontosaurus annectens and Anatotitan copei overlapped temporally - hence them both being depicted as prey for Tyrannosaurus. (I'm sorry, but that's how most people know their Late Cretaceous hadrosaurs - which tyrannosaur ate them!)
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Post by stoneage on Apr 2, 2011 20:51:22 GMT
There's a good explanation here: en.wikipedia.org/wiki/Edmontosaurus#Anatosaurus_to_the_presentThe short version: Some scientists decided that the Anatosaurus specimens which carried that name actually belonged to a species of Edmontosaurus. However, some specimens previously thought to be Anatosaurus did not belong o Edmontosaurus, so those needed a new name, which they called Anatotitan. I should note that not everybody agrees with this. There is new research in the works that shows the original idea may gave been right, and that Edmontosaurus annectens (=Anatosaurus) is the same thing as Anatotitan. Similar to the Toroceratops hypothesis, the flat, famous duck-like bill and giant size that marks Anatotitan might have developed late in life. If that's true, then Anatosaurus annectens might be a valid name for this genus. Alternately, since this would also mean there was only one species of hadrosaur in the Hell Creek formation, the right name might well be Trachodon after all (it's the oldest name for any duckbill remains in that time period). I don't think they could name it Trachodon because it was only known from some teeth. And as I understand it they can't tell what Hadrosaur they came from since Hadrosaur teeth are virtually all the same. |
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Post by dinoguy2 on Apr 2, 2011 22:18:24 GMT
I don't think they could name it Trachodon because it was only known from some teeth. And as I understand it they can't tell what Hadrosaur they came from since Hadrosaur teeth are virtually all the same. Yes, hadrosaur teeth are pretty much indistinguishable (or at least, nobody has studied them enough to find ways to distinguish them yet). But if we're pretty sure there was only one hadrosaur in a given environment, there's nothing to distinguish it *from* (except time traveling corythosaurs maybe?), so it could reasonably go by the oldest available name. Also correct, but there are several species within Edmontosaurus. The timeline goes something like: Edmontosaurus regalis: 73-70 million years ago Edmontosaurus annectens: 68-65 million years ago Anatotitan copei: 65 million years ago Whether or not to place Anatosaurus annectens in Edmontosaurus or in its own genus is somewhat of a subjective opinion (but then again, so is placing Brontosaurus excelsus in the same genus as Apatosaurus ajax). Like Brontosaurus, abandoning anatosaurus is just an opinion, but one that everybody follows nowadays. |
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Post by Horridus on Apr 3, 2011 0:55:08 GMT
Hasn't more than one cladistic analysis placed A. excelsus firmly within Apatosaurus? Just saying some opinions are more valid than others (to go somewhat Orwellian on you). Not sure what with the situation is with Edmontosaurus annectens in that respect.
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Post by stoneage on Apr 3, 2011 0:59:14 GMT
Hasn't more than one cladistic analysis placed A. excelsus firmly within Apatosaurus? Just saying some opinions are more valid than others (to go somewhat Orwellian on you). Not sure what with the situation is with Edmontosaurus annectens in that respect. ;D You mean like your opinion? |
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Post by Horridus on Apr 3, 2011 1:29:19 GMT
Hasn't more than one cladistic analysis placed A. excelsus firmly within Apatosaurus? Just saying some opinions are more valid than others (to go somewhat Orwellian on you). Not sure what with the situation is with Edmontosaurus annectens in that respect. ;D You mean like your opinion? Well, the conensus opinion of the scientific community YES, MY OPINION. |
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Post by dinoguy2 on Apr 3, 2011 14:48:13 GMT
Hasn't more than one cladistic analysis placed A. excelsus firmly within Apatosaurus? Just saying some opinions are more valid than others (to go somewhat Orwellian on you). Not sure what with the situation is with Edmontosaurus annectens in that respect. Cladistic analysis shows that excelsus is the closest relative of ajax and louisae. Whether or not to call the group that contains all these species "Apatosaurus" is a matter of opinion. There's no rule saying you can't give each one their own label (Apatosaurus ajax, Brontosaurus excelsus, Parabrontosaurus louisae or something). People get used to calling dinosaurs only by their genus names, forget that genus is not a thing, it's a group of things, same as family. Apatosaurus is not a single entity any more than Diplodocidae is a single thing. At least diplodocidae has a formal definition: Apatosaurus does not. It can mean anything you want it to mean. A similar example is Baryonyx and Suchomimus. Cladistic studies always show that Bary and Sucho are each others closest relatives. Some people think that therefore they should both be considered species within the single genus Baryonyx. Some think we may as well keep them as separate genera. There's no scientific answer, because it's not a scientific question. The scientific question (how are they related?) is settled. The only question now is a matter of what names we should choose to give them. |
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Post by Horridus on Apr 3, 2011 16:17:55 GMT
Well, yes, I wasn't disputing that. That's just taxonomy, which is indeed a matter of opinion. However I'd argue that some lumpings are better supported than others through research, even if a genus does remain, in the end, an artificial construct (I mean, arguably a species is too - I think you've made that point before).
(Something tells me I'm suffering from foot-in-mouth with my wording here...gaaahhh...)
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Post by Griffin on Apr 3, 2011 22:07:04 GMT
Yeah its different with modern animals since we have common names for them. Sometimes I feel people forget that when talking about dinosaurs.
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) but when I was younger all the dinosaur books had Anatosaurus in them. Now I hear Anatotitan. Are these different dinosaurs? Did it suddenly come into fashion to name all hadrosaurs ____titan (as in Olorotitan)? Because personally I think it's an awful name. 
