Talk:Cosmopolitodus

Requested move 2 April 2017

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: no consensus. Been relisted twice without a clear consensus being developed. No prejudice against another RM in the near future if better sourcing can be found that would alter the discussion. (non-admin closure) TonyBallioni (talk) 14:13, 24 April 2017 (UTC)

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Isurus hastalis → Carcharodon hastalis – the new name for the species. I could not put in the requested moves place because it kept on causing a error message Flow 234 (Nina) talk 10:58, 2 April 2017 (UTC) --Relisting. Anarchyte (work | talk) 06:44, 10 April 2017 (UTC)--Relisting. Yashovardhan (talk) 10:54, 17 April 2017 (UTC)

• Comment Ehret's 2012 paper is behind a paywall for me, but I can't figure out some pretty basic facts about the taxonomic history of this species. Was it first described as Isurus? If so, was it ever placed in Carcharodon prior to Ehret? If not, are there post 2012 reliable secondary sources that accept Ehret's placement? Fossilworks is a sometimes reliable secondary source that is following Ehret, but they don't seem to properly indicate the original genus, which throws their reliability into doubt in this case. Plantdrew (talk) 01:27, 3 April 2017 (UTC)

• Weak support since it's been relisted with no other input than my comment. Assuming good faith in nomination, and following Fossilworks treating this species as Carcharodon. Still would like to see another source for placement in Carcharodon though. Plantdrew (talk) 15:36, 10 April 2017 (UTC)

• Weak Keep Ehret, 2012 is probably the most recent real attempt to rename this species but the literature has been back and forth between other genera (Isurus and Cosmopolitodus) for years. Might be safe to just keep it as I. hastalis until the dust settles. Ryan shell (talk) 21:51, 10 April 2017 (UTC)

@Ryan shell: Can you confirm the original genus? Isurus show authorship for this species as "Agassiz 1843" (no parentheses). Plantdrew (talk) 22:21, 10 April 2017 (UTC)

@Plantdrew: This story is bound to get complicated but I'll do my best. Agassiz named it O. hastalis back in the 1840s. Her originally put it in Oxyrhynchus which as far as I can tell is a defunct genus. Meanwhile there are plenty of researchers who use C. hastalis as recently as this year - the original move to Cosmotolitodus is a fairly old one (http://www.sciencedirect.com/science/article/pii/S0895981116302127 this article refers to Glickman, 1964]). Agasiz also named Isurus as a genus in the same work, he just didnt put hatalis in it at the time. I have yet to fing the person to coin Isurus hastalis as opposed to Oxyrhina or Cosmopolitodus, but the name is still around in the literature. Hope all this helps! Ryan shell (talk) 01:11, 11 April 2017 (UTC)

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The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

Monotypic genus

No monotypic genus should ever have a separate species article. The two should be merged to the genus level, per palaeo project guidelines. FunkMonk (talk) 18:36, 10 November 2018 (UTC)

Carcharodon vs Cosmopolitodus and Cladistic vs Traditional

In the moment when this article gets cleaned up some time, we need to tackle the issue regarding what scientific name we are exactly going to give C. hastalis for this article in its title and elsewhere. Currently, this article uses Cosmopolitodus, but in reality there isn't a consensus in the scientific community on whether the genus should be that or Carcharodon, although the GWS-ancestry concept remains settled. I would be guessing that usually the genus that is used the most in literature would be the one preferred for the title of this article, but a majority agreement isn't really clear here.

However, I believe that the general issue causing the dispute boils down to a recognition of cladistics and paraphyly; usually the Carcharodon proponents are based on recognition of classification rules in cladistics (of which the given genus is correct under a cladistical definition; Cosmopolitodus would be incorrect due to paraphyly), while the Cosmopolitodus proponents appear to regard less on cladistical rules for a more traditional way of taxonomy (of which this genus would also be correct under such rules; paraphyly is allowed here). It seems to be that scientists in general might be leaning closer on adopting cladistics-based classification (i.e. preference of Otodus over Carcharocles regarding the genus of Megalodon), but I am not exactly sure on that. Given this, would it be better to abide by the cladistical rules and rename this article to Carcharodon hastalis or just keep with the status quo?

This goes the same with other shark taxa, which are given distinct genera but should be merged with existing ones under a cladistical definition if their evolutionary hypotheses are true (i.e. all species such as Macrorhizodus within the lineage that split from the Isurus lineage around 60-40 mya and culminating into the GWS being reassigned to Carcharodon as would be prescribed under cladistical rules)

Alternatively, we could avoid the scientific name dispute altogether and use a vernacular name. It appears that the most used common name for the shark is the broad-toothed mako or a variation, but almost all mentions use it informally.

TLDR: If a scientific name is disputed on cladistics vs traditional lines, should the title prefer the cladistical name; and should any scientific name generally be represented on an article by its cladistical name regardless of if a scientific name that does not respect cladistical rules is more widely used due to wider attention by respective publishers? Macrophyseter | talk 01:27, 3 November 2020 (UTC)

I guess in general we should just follow what most sources do, while stating clearly that there are alternative schemes. But of course, it appears it's hard to figure out which is the more prevalent use, so I guess we would go with the most long-standing usage. FunkMonk (talk) 01:38, 3 November 2020 (UTC)

Move to Carcharodon

• The Shark-References database (which may not be entirely perfect, but we need some sort of standardization for shark taxonomy) classifies hastalis in Carcharodon, although it still classifies planus in Cosmopolitodus. There is also now a recent study that also classifies C. hastalis in Carcharodon and has erected the new combination Carcharodon planus for C. planus, resolving the last remaining major issue about this genus' taxonomy. Is it time for it to be subsumed into Carcharodon? The genus has always made little cladistic sense given paraphyly. Geekgecko (talk) 22:41, 15 December 2023 (UTC)

  The entire subject is messy. Even if we ignore the old cladistic vs. traditional squabble discussed above, Carcharodon and Cosmopolitodus still remain in shared use as of recent. Who prefers which depends on their opinion on whether (1) serrations vs. non-serrations are sufficient to separate genera and (2) C. plicatilis is a distinct species or just a variant of hastalis. It's been argued directly[1] and implied[2] that a valid C. plicatilis can make a monophyletic Cosmopolitodus (regardless of the uncertainty brought by[3] of which form evolved into C. carcharias). Macrophyseter | talk 07:20, 22 May 2024 (UTC)