Ancient Jaguars

[Balam]

(06-27-2020, 05:29 AM)tigerluver Wrote:

(06-27-2020, 04:09 AM)GuateGojira Wrote: I am interesting in check the data that they used to calculate those huge weights for Panthera onca mesembrina, because the data that I have do not support that. This is the data that I have at hand about that population, compared with modern jaguars and the giant Panthera onca augusta:

*This image is copyright of its original author

*This image is copyright of its original author

*This image is copyright of its original author

*This image is copyright of its original author

Although I don't have the real size of this large skull, using the scale bar in the first picture I calculare a greatest lenngth of a little over 32 cm. However, when I use the other pictures, I obtain 34 cm and 33.5 cm respectively. With this wide variation in length (32 - 34 cm), I don't dare to state a length from this skull. I am still searching the original document, but I only know that this specimen came from Talara, Peru.

I have attached the P. o. mesembrina dataset. That mass is from a 30.2 mm long (AP measurement) M1. Here's the caveat, all other fossil P. onca M1 they have recorded are quite a bit smaller and more in the range of a jaguar. They used this fact as support that "P. o. mesembrina" is actually P. atrox. In my opinion, the statistics support that idea too and this is P. atrox, not P. onca.:

*This image is copyright of its original author

Also, what is the source of those excerpts? Thanks.

I have issues believing those remains belong to P.atrox due to de lack of fossil evidence found in the northern part of the Andes or South America for that matter, in the article they described an illustration found at cave of jaguar-like creature they used to determine the aspect of P.atrox. While not impossible, I see it much more plausible that those illustrations were depicting true jaguars and hence the resemblance:

*This image is copyright of its original author

If P.atrox is a true descendant of P.spelaea and we know for a fact the cave lion had a very similar coat to that of extant lions, I don't see how P.atrox would then evolve jaguar-style roses, especially when it lived in a grassland environment where a plain light coat would've made more sense. Reply