Talk:Megaraptora
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Possible Antarctic megaraptorid
[edit]https://dc.ewu.edu/cgi/viewcontent.cgi?article=1839&context=theses Turns out there's a possible megaraptorid maxilla fragment recovered from the Maastrichtian Lopez de Bertodano Formation of the Antarctic Peninsula.
Are Megaraptorans Carnosaurs or Tyrannosauroids?
[edit]Novas et al. (2012) found Megaraptorans as Tyrannosauroids. The pages for Megaraptora, Tyrannosauroidea, and Megaraptor reflect this. However, Zanno & Makovicky (2013) recovered Megaraptorans as Carnivorans (the tree can be seen on the Siats (dinosaur) article). Which classification is Wikipedia assuming correct? In my opinion, I think the newer study should be assumed as "correct". — Preceding unsigned comment added by Shuvuuia (talk • contribs) 20:42, 9 June 2014 (UTC)
Nevermind, a new study has shown they are tyrannosauroids — Preceding unsigned comment added by Shuvuuia (talk • contribs) 18:35, 22 June 2014 (UTC)
- This is an ongoing debate. Neither side is "correct". Both have evidence to support their position, and neither position is much better supported than the other right now. That's science. Are they carnosaurians or tyrannosauroids? We don't know. Dinoguy2 (talk) 20:31, 22 June 2014 (UTC)
- Apparently, a new skull of Megaraptor suggests megaraptorans to be tyrannosauroids, but I would say we should reserve total judgement until the idea is, like the dinosaurian origins of birds, the dominant POV in the literature before claiming it as fact. Dromaeosaurus is best dinosaur (talk) 18:21, 3 August 2014 (UTC)
- Yes, is an ongoing debate, but the sentence: "From these debated relations, megaraptorans have been, at the moment, simply placed by some under avetheropods, mostly to remain neutral between carnosaurs and coelurosaurs." is a personal opinion. I suggest to delete it. TaTo 713 (talk) 22:19, 2 June 2015 (UTC)
- It's not really a personal opinion on the matter, though; it's just that some palaeontologists simply don't want to pick sides and just have the clade listed as "avetheropodans of controversial relations" because there's no consensus on what phylogeny is "correct" at this point. Dromaeosaurus is best dinosaur (talk) 16:18, 5 June 2015 (UTC)
Headers in the classification section
[edit]From my research, the transition between the different hypotheses of megaraptoran classification is fairly straightforward and time-segregated. Benson, Carrano, & Brusatte (2010) found them to be neovenatorids in lieu with earlier support for placement within Carnosauria. Carrano's 2012 theropod phylogeny supported this placement, as did the Siats description (2013). Novas and his colleagues (2013) re-evaluated the neovenatorid dataset in detail, looking over each character and showing how most were probably not autapomorphic for a Neovenator + Megaraptora clade. Since their study was published, there has not been a study which shifts the consensus back towards Neovenatoridae. That's not to say that there is complete consensus. The Gualicho and Murusraptor papers (both 2016) refused to comment on the matter, and they incorporated both the BCB (2010) and the Novas (2013) studies. The third hypothesis, the basal coelurosaur hypothesis, was recently (formally) proposed in 2018, during the Tratayenia description.
The point I'm trying to make is that the transition between the different hypotheses comes in different chunks. 2010-2013 was dominated by the Neovenatoridae hypothesis, 2013-2018 either preferred the tyrannosauroid hypothesis or remained neutral, and the 2018 basal coelurosaur hypothesis is too recent to come to any conclusions about. It seems that support for the neovenatorid hypothesis is lower than the tyrannosauroid hypothesis; BCB have not yet formulated a counterargument to Novas et al. (2013)'s deconstruction of their study. I wouldn't go as far as to say there's a consensus, and I'm not trying to downplay the impressive amount of homoplasy within Megaraptora, but based on published papers and their content, there are distinct "eras" in megaraptoran classification where certain hypotheses have support. Almost every 2010-2013 megaraptoran paper discusses them in the context of neovenatorids, while post-2013 papers discuss them in the context of tyrannosauroids, coelurosaurs, or avetheropods as a whole. You can search for these papers on Google Scholar if you need confirmation. I have not found any evidence that the "neovenatorid era" is making any sort of comeback, at best certain paleontologists stay neutral on the subject. The headers I have been trying to establish are meant to portray this change in thought among paleontologists. Fanboyphilosopher (talk) 02:53, 9 January 2019 (UTC)
- The 2016 papers remaining neutral is a statement that Neovenatoridae is still on the table; there were two ideas at the time and it was inconclusive which of the two were better supported. So it's more like Neovenatoridae -> Tyrannosauroidea -> Could be either -> Perhaps basal coelurosaurs? As such, framing the carnosaur idea as thrown-out after 2013 is inaccurate. Also, I'm still not sure how I feel about the 2016 studies in the tyrannosauroid section when once again neither even mention that idea directly. That's my issue with the whole thing - you're basically giving single paragraphs subsections (the sentences merely explaining what the cladogram is doesn't really count), which is generally discouraged, and than throwing some extra paragraphs relevant to all three into one of them rather randomly. Hence I feel this entire section doesn't work under headers. Lusotitan (Talk | Contributions) 03:27, 9 January 2019 (UTC)
- I've been looking at more papers, and megaraptoran classification is rewriting itself at a drastic rate. I've rewritten, reformatted, and corrected part of the classification in response. Basically, when the 2016 Gualicho analysis reanalyzed the Novas dataset, it found that Allosauroidea was paraphyletic, with neovenatorids leading to megaraptorans and megaraptorans leading to coelurosaurs. The 2018 Tratayenia study backtracked to create a polytomy in Avetheropoda. And the 2018 gondwanan tyrannosauroid paper backtracked further to place Neovenator within a monophyletic Allosauroidea and Megaraptora within basal Coelurosauria. The 2016 papers were sometimes neutral (and sometimes not), but all of the 2018 papers have clearly supported the idea that megaraptorans were coelurosauroids rather than allosauroids. The tyrannosauroid hypothesis has been constantly refined, expanded, and corrected for over 5 years, and at this point it has transformed into the basal coelurosaur hypothesis. The neovenatorid hypothesis is way past its heyday, and the errors in the BCB analysis have been known since 2013. It's a continuous shift in consensus. Megaraptorans started out as neovenatorids, then a new analysis proposed they were tyrannosauroids. People weren't sure which to trust since it's wise to be wary about new theories (Ornithoscelida, for example). However, the tyrannosauroid hypothesis was becoming increasingly more mainstream, and by 2016 most papers either discussed them as equals or leaned towards Tyrannosauroidea. Now, ~2.5 years later, the tyrannosauroid hypothesis has been refined into the coelurosaur hypothesis over several papers, and the neovenatorid hypothesis is barely even mentioned. Fanboyphilosopher (talk) 04:39, 9 January 2019 (UTC)
- Even then, this seems like excessive use of headers - again, two of them are (effectively) single paragraph sections, which ideally shouldn't exist, and the last paragraph of the tyrannosaur subsection is still 2/3 unrelated to tyrannosauroids. I still feel this reads better with no sub-headers. Lusotitan (Talk | Contributions) 20:25, 9 January 2019 (UTC)
- I've been looking at more papers, and megaraptoran classification is rewriting itself at a drastic rate. I've rewritten, reformatted, and corrected part of the classification in response. Basically, when the 2016 Gualicho analysis reanalyzed the Novas dataset, it found that Allosauroidea was paraphyletic, with neovenatorids leading to megaraptorans and megaraptorans leading to coelurosaurs. The 2018 Tratayenia study backtracked to create a polytomy in Avetheropoda. And the 2018 gondwanan tyrannosauroid paper backtracked further to place Neovenator within a monophyletic Allosauroidea and Megaraptora within basal Coelurosauria. The 2016 papers were sometimes neutral (and sometimes not), but all of the 2018 papers have clearly supported the idea that megaraptorans were coelurosauroids rather than allosauroids. The tyrannosauroid hypothesis has been constantly refined, expanded, and corrected for over 5 years, and at this point it has transformed into the basal coelurosaur hypothesis. The neovenatorid hypothesis is way past its heyday, and the errors in the BCB analysis have been known since 2013. It's a continuous shift in consensus. Megaraptorans started out as neovenatorids, then a new analysis proposed they were tyrannosauroids. People weren't sure which to trust since it's wise to be wary about new theories (Ornithoscelida, for example). However, the tyrannosauroid hypothesis was becoming increasingly more mainstream, and by 2016 most papers either discussed them as equals or leaned towards Tyrannosauroidea. Now, ~2.5 years later, the tyrannosauroid hypothesis has been refined into the coelurosaur hypothesis over several papers, and the neovenatorid hypothesis is barely even mentioned. Fanboyphilosopher (talk) 04:39, 9 January 2019 (UTC)