Brontosaurus is back

[Pachyrhinosaurus]

I'm happy about this, but as Blade said, why is A. louisae still not included? I think it is more similar to brontosaurus than it is to A. ajax.

[Dinoguy2]

I'm happy about this, but as Blade said, why is A. louisae still not included? I think it is more similar to brontosaurus than it is to A. ajax.

You can read the analysis if you want nitty gritty details. Remember that they're comparing tiny features of bones, not overall look. You're right that louisae does have proportions a bit more like excelsus. But all that means is that they look more like the ancestral apatosaurine and Ajax evolved away from that look. Also keep in mind the classic slender Ajax specimen illustrated by Hartman is juvenile. Compare the scale bars - his Ajax is smallest of the three, but other Ajax specimens represent some of the largest known diplodocids.

[Pachyrhinosaurus]

I'm happy about this, but as Blade said, why is A. louisae still not included? I think it is more similar to brontosaurus than it is to A. ajax.

You can read the analysis if you want nitty gritty details. Remember that they're comparing tiny features of bones, not overall look. You're right that louisae does have proportions a bit more like excelsus. But all that means is that they look more like the ancestral apatosaurine and Ajax evolved away from that look. Also keep in mind the classic slender Ajax specimen illustrated by Hartman is juvenile. Compare the scale bars - his Ajax is smallest of the three, but other Ajax specimens represent some of the largest known diplodocids.

I never thought about it like that. Its interesting to see, too that the slenderness which I had seen characteristic of A. ajax is a juvenile trait.

[Blade-of-the-Moon]

Is juvenile the correct term? I think Scott said it was a sub-adult before? I know ours is a bit smaller, being around 67' long.

[laticauda]

I remember having this conversation a little while ago here on the forum.  I listened to  interviews from Bob Bakker and Matt Mossbrucker gave to palaeocast.com. http://dinotoyblog.com/forum/index.php?topic=2577.0 

Now, how do we separate which is what in the toy world?   

[Patrx]

I can't tell, does this new paper have anything to do with the material Bakker and Mossbrucker were working on back then? The specimen they called "Kevin"?

[Newt]

Mentioned here:

"Diplodocus lacustris, YPM 1922*. The original type material of D. lacustris comprises
teeth, a premaxilla, and a maxilla (Marsh, 1884). However, personal observations at YPM
reveal that the cranial bones clearly belong to Camarasaurus or a morphologically similar
taxon, and that there is no relationship between them and the teeth. Mossbrucker & Bakker
(2013) described a newly found putative apatosaur maxilla and two premaxillae from the
same quarry, proposing that they might belong to the same individual as the teeth of YPM
1922. However, given the lacking field notes from the first excavations, such a referral
will be difficult to prove. Therefore, in the present analysis, only the teeth were scored for
D. lacustris."

[Dinoguy2]

I remember having this conversation a little while ago here on the forum.  I listened to  interviews from Bob Bakker and Matt Mossbrucker gave to palaeocast.com. http://dinotoyblog.com/forum/index.php?topic=2577.0 

Now, how do we separate which is what in the toy world?   

Hard without knowing which specimen they're based on. The Wld Safari might be Brontosaurus just by eyeballing it. I've never seen a proper, massive necked Apatosaurus figure though, aside from Sideshow (so I guess Papo's is Apatosaurus too). The iriginal Carnegie was probably based on A. louisae, just because, well, it's Carnegie...

[HD-man]

Rejoice! Brontosaurus is a valid genus once again!

Maybe ( http://www.theguardian.com/science/2015/apr/07/brontosaurus-is-back-new-analysis-suggests-genus-might-be-resurrected ). I'm reserving judgement til "other researchers...test the evidence for resuscitating Brontosaurus".

[Dinoguy2]

Rejoice! Brontosaurus is a valid genus once again!

Maybe ( http://www.theguardian.com/science/2015/apr/07/brontosaurus-is-back-new-analysis-suggests-genus-might-be-resurrected ). I'm reserving judgement til other paleontologists test Tschopp et al.'s hypothesis.

As people have pointed out in these interviews, it's not really a hypothesis that can be tested. Every one agrees 100% that excelsus is a distinct species. Whether or not excelsus should go into a box labelled Apatosaurus or a box labelled Brontosaurus is a matter of taste. Tschopp's innovation is creating a mathematical model for deciding how big each box is. What remains to be seen is if other people like the new label he made and/or if they like his method for making new boxes.

None of that is science, and none of that is a hypothesis that can be tested against reality, it's all making and labelling boxes to put species in. What Tschopp did do for science is the most though analysis of how all these SPECIES are related than has ever been done. What boxes we put those species in is not and has never been a scientific question. People don't like to admit that, because it means Brontosaurus was originally discarded on somebody's whim, nothing to do with science, which is true. Elmer Riggs decided that the label Apatosaurus should be moved to a larger box, a box big enough to envelop Brontosaurus. There was no scientific reason for that.

Similarly, Tschopp has now put Elosaurus and Eobrbontosaurus into the big Brontosaurus box. His reason is that he followed the model he made up for deciding what goes in which box, which is at least some kind of standard, but it's still a standard he himself made up. There's no scientific reason you couldn't still put Apatosaurus, Brontosaurus, Elosaurus, and Eobrbontosaurus each into their own small little box.

[Derek.McManus]

At least in the popular imagination I don't think Brontosaurs ever went away..lol

[HD-man]

As people have pointed out in these interviews, it's not really a hypothesis that can be tested. Every one agrees 100% that excelsus is a distinct species. Whether or not excelsus should go into a box labelled Apatosaurus or a box labelled Brontosaurus is a matter of taste. Tschopp's innovation is creating a mathematical model for deciding how big each box is. What remains to be seen is if other people like the new label he made and/or if they like his method for making new boxes.

Tell that to Tschopp ("Other researchers will now need to test the evidence for resuscitating Brontosaurus": http://www.theguardian.com/science/2015/apr/07/brontosaurus-is-back-new-analysis-suggests-genus-might-be-resurrected ).

[suspsy]

Now if only Dynamosaurus imperiosus could turn out to be a distinct genus from T. Rex. I love that name.

[Paleogene Pals]

That means I can collect a Brontosaurus and an Apatosaurus model now! Such times we live in. 

[Dinoguy2]

As people have pointed out in these interviews, it's not really a hypothesis that can be tested. Every one agrees 100% that excelsus is a distinct species. Whether or not excelsus should go into a box labelled Apatosaurus or a box labelled Brontosaurus is a matter of taste. Tschopp's innovation is creating a mathematical model for deciding how big each box is. What remains to be seen is if other people like the new label he made and/or if they like his method for making new boxes.

Tell that to Tschopp

Several people already have told that to him, if you follow some paleos on FB Because before this study there was no definition of what the word "genus" means, it's no so much about seeing if others test it but if others accept his definition or make up their own. Genera aren't real, only species are, so there's nothing to test. What test would you do on a lion and a leopard to find out if they're the same genus or not?

Also, see Mike Taylor's comments: http://svpow.com/2015/04/07/welcome-back-brontosaurus-and-other-first-thoughts-on-tschopp-et-al-2015/

"As usual in phylogenetic taxonomy, it comes down to what we decide as a community constitutes "diagnosably distinct".

And Andrea Cau:
"On the (abused) taxonomic side of the paper. Until someone explicitly defines Apatosaurus as "everything closer to A. ajax than B. excelsus" and Brontosaurus as "everything closer to B. excelsus than A. ajax", the question of what is Brontosaurus/Apatosaurus remains totally subjective, regardless to the metric used to "quantify" a genus. This just because taxa-name are taxo-nomic issues, not systematic (phylogeny-ontogeny-stratigraphy problems)."

That means I can collect a Brontosaurus and an Apatosaurus model now! Such times we live in. 

You could have before... do you have any models of A. excelsus? Those are Brontosaurus now

[Stuckasaurus (Dino Dad Reviews)]

The only question now is figuring out which Apatosaurus toys are which!

The Sideshow model no doubt represents A. ajax, and since Safari's neck has a flattened underside, I've taken that to mean they are attempting to represent the wide neck of A. ajax as well. Just not sure what the Carnegie model represents, though it might be too much of a generic-opod to tell. Since the neck is not obviously widened side-to-side, it's possible it represents a Brontosaurus, or maybe A. louisae.

[Halichoeres]

We are all assuming that the results of the cladistic analysis are sound, which is possible but not at all certain. For example, Hillis et al. (2003, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2943953/) show (see the section, "with finite resource, is it better...") that a phylogenetic analysis generated with many data can give you high confidence in an incorrect result. This study used 477 morphological characters, which is probably too many for a group, like sauropods, where many many species are known from extremely fragmentary remains. This is because the parsimony algorithm assumes independence of those characters, an assumption which is always violated to some extent, but is violated more egregiously as you increase the number of characters.

The excessive atomization of characters by itself doesn't necessarily mean that the analysis yielded the wrong answer. But it does make me less apt to proclaim Brontosaurus resurrected just yet.

[sauroid]

the differences between the species and genera are very subtle in terms of skeletal differences and only the experts could tell them apart. their external morphological uniqueness (especially colorations/markings) could have been the only way to tell them apart.

[Ridureyu]

Drat.  This news came right after I told someone he was ignorant and anti0science for believing in the brontosaurus.  Now he's enlightened and pro-science, at least until the general consensus changes.

[stoneage]

   I first saw this news on TV.  They titled it Jurassic Park Was Right.  Then they showed a picture of the Brachiosaurus from the first movie. What??