palaeozoologist In reply to kret-spec [2018-05-14 22:17:26 +0000 UTC]

Thanks for noticing, it's much appreciated!

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palaeozoologist In reply to bricksmashtv [2016-05-24 04:50:42 +0000 UTC]

Unfortunately, I do not have a lot of spare time at present, so not sure I could provide a formal review, but if you intend to submit it to the preprints, I would be willing to make some short comments at that time. Same issue with co-authoring, unfortunately do not have much time for that either. It would depend on what exact kind of involvement would be needed.

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bricksmashtv In reply to palaeozoologist [2016-05-24 04:53:10 +0000 UTC]

Oh, that's okay. I plan on a full published peer-reviewed article. Do you know anyone else who would be willing to review for me (I've already contacted Nima, so anyone else)?

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palaeozoologist In reply to bricksmashtv [2016-05-29 23:24:21 +0000 UTC]

I know that anyone I would suggest are also quite busy, so I'm afraid I'm not of much help. Sorry

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bricksmashtv In reply to palaeozoologist [2016-05-29 23:25:25 +0000 UTC]

Oh, it's OK

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palaeozoologist In reply to Terizinosaurus [2015-08-28 00:26:13 +0000 UTC]

Thanks for the watch!

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Terizinosaurus In reply to palaeozoologist [2015-08-28 08:31:45 +0000 UTC]

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palaeozoologist In reply to JuanH91 [2014-09-06 20:04:08 +0000 UTC]

Yes, I am in progress of doing one. Hopefully it will be done by tomorrow. I agree that its mass is substantially overestimated. Watch this space.

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palaeozoologist In reply to darklord86 [2014-03-06 01:47:39 +0000 UTC]

Thank you!

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darklord86 In reply to palaeozoologist [2014-03-06 05:33:40 +0000 UTC]

No problem!

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palaeozoologist In reply to TyrannosaurusPrime [2013-11-29 00:06:56 +0000 UTC]

Well, I don't know much about morphometrics, so I don't really have any major thoughts. The only thing I will point out is that one of the methods they used in the study was UPGMA, which is a phenetics-based method. To quote Wikipedia, "In a phylogenetic context, UPGMA assumes a constant rate of evolution...and is not a well-regarded method for inferring relationships unless this assumption has been tested and justified for the data set being used." (en.wikipedia.org/wiki/UPGMA) The problem with phenetics is that it does not account for evolutionary relationships, and therefore is inferior to cladistics when trying to account for evolutionary relationships (see: en.wikipedia.org/wiki/Phenetic… . So it tells us that the Triceratops and Torosaurus specimens are morphologically distinct and cluster together (which we already knew), but I'm not sure what that means in regards to whether they are truly distinct species. So for instance, fig. 7 I believe is possibly misleading in this regard. It shows morphological distinctness, but what does this mean for ontogeny vs. species? This doesn't mean I think their study is wrong, it's just hard for me to tell if these methods are being appropriately used.

I would like to see a similar study on closely related living taxa that explicitly test ontogenic differences versus species differences  to test whether these methods are reliable. This may have already been done, but like I said, I don't know enough about it.

One thing that makes me wonder about this is deer. Deer are sexually dimporphic - (in general females don't have antlers, while males do have them) and on top of that, the antlers of male deers continually change as they get older (peramorphosis) (www.deerhunting.ws/skulls.jpg) . If we took extremely close related species, but only used young adult specimens of one species, and old adult specimens of the other, could we reliably distinguish the species vs ontogenetic stages? My basic question is this: Can morphometrics reliably distinguish between ontogeny-related difference versus species related differences? I would need to see studies of this sort done on living animals (like deer, for example) for which we do know these differences already and see if they are matched by morphometric methods. Until I see that, it is difficult for me to know whether the study actually demonstrates what it says it demonstrates.

Ultimately, if Torosaurus and Triceratops truly are distinct, juvenile Torosaurus specimens that are clearly juvenile Torosaurus will be found.

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TyrannosaurusPrime In reply to palaeozoologist [2013-12-03 22:52:07 +0000 UTC]

I see. Thanks.

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palaeozoologist In reply to TyrannosaurusPrime [2013-12-04 00:50:40 +0000 UTC]

No problem!

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TyrannosaurusPrime In reply to palaeozoologist [2013-12-04 19:23:54 +0000 UTC]

What do you think of these?

theropoda.blogspot.it/2013/12/…

theropoda.blogspot.it/2013/11/…

theropoda.blogspot.it/2013/11/…

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palaeozoologist In reply to TyrannosaurusPrime [2013-12-10 02:41:23 +0000 UTC]

I think I good case is made that Spinosaurus was likely smaller than Tyrannosaurus, based off of known specimens. Which is really not all that surprising, considering how bad most dinosaur size estimates tend to be. That said, since we have a lot smaller sample size of Spinosaurus, and the specimens are far less complete than what we have for Tyrannosaurus it's difficult to say much about average or maximum sizes between them.

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TyrannosaurusPrime In reply to palaeozoologist [2013-12-12 18:52:05 +0000 UTC]

I see. In other news: a mummified Edmontosaurus regalis showed that the animal had a fleshy comb like a cock: phenomena.nationalgeographic.c…

phys.org/news/2013-12-duck-bil…

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palaeozoologist In reply to TyrannosaurusPrime [2013-12-15 01:46:30 +0000 UTC]

Cool!

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palaeozoologist In reply to TyrannosaurusPrime [2013-06-15 21:37:04 +0000 UTC]

Excellent!

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palaeozoologist In reply to TyrannosaurusPrime [2013-04-06 18:39:34 +0000 UTC]

Thanks!

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TyrannosaurusPrime In reply to palaeozoologist [2013-04-07 13:08:28 +0000 UTC]

No problem. Sucks that Agustinia isn't as bizzare as we thought, but then again, who needs that when we already have Amargasaurus?

On another note, do you think Megalodon belongs into the Carcharodon or Carcharocles genus?

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palaeozoologist In reply to TyrannosaurusPrime [2013-04-12 14:24:57 +0000 UTC]

I've suspected for a while that at least some of the "osteoderms" of Agustinia looked more like dorsal ribs, so I'm glad to see that is supported here (although it makes it a lot less interesting).

As for Megalodon, it depends on what you think a "genus" should be (as it is completely arbitrary). At least two recent studies ([link] and [link] ) both suggest that the white shark (Carcharodon carcharias) is more closely related to mako sharks (which are in the genus Isurus) than to the megatooth sharks (C. megalodon). If true, then the only way you could justify putting Megalodon in Carchardon (and keeping it monophyletic) would be by putting the makos into Carcharodon as well. So far, it looks like Megalodon is closer to Otodus. So I'd favor putting it in it's own genus Carcharocles.

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palaeozoologist In reply to dracontes [2013-03-14 18:19:56 +0000 UTC]

Well, that's really odd. I'm guessing it's a glitch. I know I've read somewhere that someone had a similar problem where they would watch someone, but then not get any message info back. Maybe it's related? It's weird, though.

So thanks for the watch! I'll try to keep it coming, although I have been vastly unproductive lately.

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palaeozoologist In reply to TyrannosaurusPrime [2013-02-19 18:44:58 +0000 UTC]

Hey! Thanks for the link. A very interesting debate and both sides make excellent points. Makes me even more uncertain about which side is right. I look forward to when some of the new research that both Jack Horner and Nick Longrich refer to is published. A very exciting debate!

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TyrannosaurusPrime In reply to palaeozoologist [2013-02-22 09:22:02 +0000 UTC]

Totally agree with you. BTW check out these Batman slapping Robin memes I made: [link] and [link]

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palaeozoologist In reply to TyrannosaurusPrime [2013-03-02 18:55:25 +0000 UTC]

The links don't work...

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TyrannosaurusPrime In reply to palaeozoologist [2013-03-02 23:44:52 +0000 UTC]

[link] [link]  

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palaeozoologist In reply to TyrannosaurusPrime [2013-03-07 03:43:56 +0000 UTC]

Hmmm...I keep getting "Page not found" errors when I try the link.

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TyrannosaurusPrime In reply to palaeozoologist [2013-03-07 09:50:08 +0000 UTC]

Never mind that. Have you seen this BTW? [link]

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palaeozoologist In reply to TyrannosaurusPrime [2013-03-09 21:07:10 +0000 UTC]

I have! It's excellent. Ceratosaurus is one of my favorite theropods, and this reconstruction makes it look even cooler. Maybe I should illustrate it

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TyrannosaurusPrime In reply to palaeozoologist [2013-03-10 13:03:53 +0000 UTC]

Okay. BTW check this out: [link]

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