Is this a big Mako tooth?

[Brett Breakin' Rocks]

The Shark Formerly Known as Mako ? ... ha !

[digit]

And it would be written as a symbol instead of a word.

 

I'll start referring to the species in precise writing by its new proper name Carcharhinus hastalis and instead of exclaiming that I found a "mako" tooth in my sifting screen I'll probably start calling these simply "White Shark" teeth or possibly by the more verbose title of "Broad-tooth White Shark" and see which one seems to stick. Don't know that there will be a consensus on this but we should probably strive to drop the term "mako" when referring to them (though it will be hard to change old habits).

 

 

Cheers.

 

-Ken

[Bone Daddy]

4 hours ago, digit said:

And it would be written as a symbol instead of a word.

 

I'll start referring to the species in precise writing by its new proper name Carcharhinus hastalis and instead of exclaiming that I found a "mako" tooth in my sifting screen I'll probably start calling these simply "White Shark" teeth or possibly by the more verbose title of "Broad-tooth White Shark" and see which one seems to stick. Don't know that there will be a consensus on this but we should probably strive to drop the term "mako" when referring to them (though it will be hard to change old habits).

 

 

Cheers.

 

-Ken

 

You have my vote on this. Of course, my memory is awful, so I may need to be reminded if I ever get my hands on another one of these.

 

[FossilDAWG]

22 hours ago, ynot said:

So I should have said--  tooth is a Carcharodon   ( Cosmopolitodus) (Isurus) hastalis , AKA. broad tooth mako. But it is a white shark

It is getting confusing!!

Tony

Labeling the tooth in the manner you suggest would be incorrect.  According to the rules of taxonomic nomenclature, names in brackets following the genus name are subgenera, not a list of previously used generic names.  Your name indicates that Cosmopolitodus is a subgenus of Carcharodon, which is incorrect.  Also the status of Isurus is very confusing in your suggested name, as "hastalis" cannot belong to two different subgenera at the same time, and anyway Isurus is not considered to be a subgenus of either Carcharodon or Cosmopolitodus.  The best way to handle this situation is, I think, to include a list of synonyms or previously used names on the specimen label or in your records.

 

I think it is also worth considering that such name changes are opinions of the researchers.  If the reasons for the name changes are convincing, other experts in the field will start to use the new combination (Carcharodon hastalis) instead of the old.  If those experts are not convinced they do not have to blindly follow the new name, but generally they will (in their publications) state their reasons for sticking with the old name and rejecting the new one.  Over time, if the majority of experts choose to accept the new name, the change will become "real".  If most experts disagree with the reasons given for the reassignment to Carcharodon and stick with Cosmopolitodus, then Cosmopolitodus hastalis will remain the "most correct" name.  Remember that these names are hypotheses about relationships, and hypotheses are expected to be based on evidence and to be constantly challenged; only strong hypotheses will survive unscathed.

 

The situation here is different from other reasons for name changes, such as synonomy or priority of names, where rules really do apply (no two species within a kingdom can have the same name, and the earliest validly published name has priority and later names for the same taxon are invalid junior synonyms).

 

Don

[sixgill pete]

Personally, I label the teeth in my collection as Cosmopolotodus hastalis. When I speak with someone about them I still refer to them as broad toothed makos. This is just my personal thoughts on the subject.

[digit]

Because new species descriptions or new combinations always include a list of all former binomials that are to be considered as synonymous. There is always a direct link from older binomials to the state-of-the-art latest one. If you are a museum and have things on public display, it is considered good form not to leave extremely outdated names on displays but the realities and costs of changing over to new names often means there is a lag. I've been told by taxonomists that while they usually try to update terminology in their collections when they are working on specimens they make no special effort to keep assistants busy relabeling all their specimens as soon as a new binomial is coined. There are many cases where a new name gets reversed and so sometimes it is most efficient to leave the older names attached till the new one settles in. A few years back some of the thin "lettuce" corals in the genus Agaricia in the Tropical Western Atlantic region were renamed Undaria (I believe a subgenus promoted to a full-fledged genus). Not all species in Agaricia made the change and the reasons for separating out a few of them seem a bit suspect--based on one author's opinion which I'm not sure I agree with. A paper published shortly after that one tried to figure out the relationship of the agaricid species and some related genera like Helioseris using DNA analysis. That cladogram (relationship tree) analysis showed the deepwater species of Agaricia were significantly different from the shallow water species but the few species that had been tossed into Undaria were all interspersed within a dense pack of other Agaricia species showing the reasons for their exclusion from this genus were probably misguided. Having these few corals in a different genus is a minor annoyance for me in the analysis of coral reef data that I work with and I'm just waiting for the day that someone writes a new paper and uses new techniques (and leverages off the DNA study) to hopefully reunite the shallow water Agaricia genus. For coral reef survey purposes I don't much care about the two deepwater species and could care less if they get sprung into a new genus.

 

They say a small town that can't support one lawyer can always support two (a nugget of truth here if you know or are a lawyer). Taxonomy seems to be another self-sustaining profession with the lumpers and splitters keeping themselves employed battling over the current names of things. People with labeled collections (or who write books using scientific names) are kept busy adhering to the latest combinations.

 

I'll just try to find some Dire Wolf, Giant Ground Sloth, and Mastodon fossils this Saturday so I don't have to remember what to call my Mako/White Shark teeth.

 

 

Cheers.

 

-Ken

[ynot]

3 hours ago, FossilDAWG said:

Labeling the tooth in the manner you suggest would be incorrect.  According to the rules of taxonomic nomenclature, names in brackets following the genus name are subgenera, not a list of previously used generic names.  Your name indicates that Cosmopolitodus is a subgenus of Carcharodon, which is incorrect.  Also the status of Isurus is very confusing in your suggested name, as "hastalis" cannot belong to two different subgenera at the same time, and anyway Isurus is not considered to be a subgenus of either Carcharodon or Cosmopolitodus.

One of the problems with not having any formal studies on fossils.

On elasmo.com they have this tooth listed in the following manor -- Cosmopolitodus (Isurus) hastalis (AGASSIZ, 1843)
extinct White shark  . Is this incorrect?

 

How does all of this effect the Cosmopolitodus (Isurus) planus (AGASSIZ, 1856)
extinct White shark ?

Does Anyone know what shark is supposed to be the ancestor of the shark C. hastalis?

 

Tony

 

[joshuajbelanger]

For the record, I got this tooth back