There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
OncaAtrox, thank you for your speedy reply. Just a couple more if you don't mind
1) Was mesembrina mostly restricted to the extreme southern end of South America in places like Patagonia? Would this suggest they largely avoided competition with Smilodon fatalis and populator?
2) Somewhat off topic but in terms of the pantherine relations to each other, would the tiger be the only entirely Asian pantherine species as even it's closest relative the snow leopard apparently have some ancestry on the female lineage side from some African cat?
(06-21-2020, 07:47 PM)Richardrli Wrote: OncaAtrox, thank you for your speedy reply. Just a couple more if you don't mind
1) Was mesembrina mostly restricted to the extreme southern end of South America in places like Patagonia? Would this suggest they largely avoided competition with Smilodon fatalis and populator?
2) Somewhat off topic but in terms of the pantherine relations to each other, would the tiger be the only entirely Asian pantherine species as even it's closest relative the snow leopard apparently have some ancestry on the female lineage side from some African cat?
Remains from mesembrina have been found from the Southern tip of the Patagonia all the way up to Washington state, only during the late Pleistocene do we see remains of them in the Patagonia still present which may suggest an earlier extinction in North America and northern South America.
In terms of interspecific conflict, it is likely that they preferred different habitats from that of other large sympatric felids or maybe different prey preferences (although based on the evidence this is unlikely), but truly research on their ecology as it relates to how they interacted with other predators is lacking.
The tiger and snow leopard are indeed the only two extant species of Pantherines who failed to establish themselves outside of Asia and probably had their roots from an earlier Pantherine known as Panthera blytheae.
On social habits, the Bocherens et al. study postulated P. spelaea was solitary given:
"In combination with evidence for fights between cave hyenas and cave lions and that cave hyenas sometimes consumed carcasses of lions during the Late Pleistocene (e.g., Diedrich, 2008, 2009a), this indicates that lions were at a disadvantage in the competition with hyenas. This could be linked to the solitary habits of cave lions in contrast with the clan behaviour of cave hyenas. This is in contrast with modern spotted hyenas and lions in Africa, where both predator species exhibit a large overlap in the prey choice (Hayward, 2006). Modern lions, even if they are smaller than the Pleistocene ones, may resist better the competition with spotted hyenas thanks to their collective behaviour."
There is this famous cave painting that potentially shows a group of cave lions:
*This image is copyright of its original author
However, given the concrete data of Bocherens et al., it is possible this is a dynamic depiction (a comic of sorts) of a single specimen hunting. Taking the depiction literally, we don't see modern lions hunt in such massive crowds as the painting shows. Doesn't rule out pride living necessarily, but does rule in a different social approach to the hunt.
Wheeler et al. postulated pride-living in P. atrox as they stated males were over-represented in the tar pits as compared to females with following data: "52% males based on femora, 59% on C, 68% on P4, 58% on the c1, and 63% on m1." More specifically, they also noted younger males specifically were over-represented based on aging via dental wear. Their line of thought is that in pride-living, young males have a higher risk of mortality. Young males would be cast out and at greater risk while young females could still have the safety of the pride and avoid death in the tar pits. As such, having more younger males in tar pits indicates pride living. There are a couple critical issues with this logic however. For one, dentitions are not necessarily good indicators of size or sex. Wheeler et al. do admit this deficiency, especially in the case of the m1. This is supported by the fact that the femora show less males as compared to what the m1 and canines indicate. Secondly, the association of increased young male mortality with social living is not supported by data. One study on leopards found that young males have equal or greater mortality than young females (Swanepoel et al. 2014). Another study on Amur tigers found subadult males had an even more dismal survival rate as compared to subadult females (Goodrich et al. 2008). With such disparities in these solitary species, increased sub-adult male mortality is not evidence for pride behavior.
06-27-2020, 04:09 AM( This post was last modified: 06-27-2020, 04:11 AM by GuateGojira )
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.
(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.
You can check the data directly from the article itself, they said the skulls and fossils from that population were unreleased so only they have access to them, but the equations used to determine the sizes are provided for both subspecies. Augusta being smaller than mesembrina.
(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.
06-27-2020, 05:45 AM( This post was last modified: 06-27-2020, 06:30 AM by 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.
(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.speleae 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.
Reasonable points. Before we discuss further, let's make sure everyone has seen the cave painting:
*This image is copyright of its original author
To start, the reference to artwork is weak, agreed. For one, a 1.5 m cat is small for a giant lion. Jaguars can however attain these body lengths. The authors use of this point to support the presence of P. atrox is weak. However, why does the presence of a jaguar painting on a rock have to exclude the presence of another cat? We have at the least the puma and Smilodon. If we take the art literally, the puma and Smilodon never happened.
Next, a bit of conjecture and theory. We know P. spelaea and P. atrox may have overlapped ranges, indicating they did not interbreed. We also know P. atrox is primitive in form like P. fossilis (Sotnikova and Foronova 2014). Perhaps the rosettes on lion cubs represent a primitive form, and thus P. atrox had rosettes. This could explain the reproductive isolation between P. spelaea and P. atrox despite sympatry. Nonetheless, this is conjecture. To be frank, that cave art doesn't show rosettes either, just dots. Probably simplified rosettes of course, but one can hope for a South American Miracinonyx.
Back to concrete data. If we stick with the reddish-brown un-patterned fur of the cave lions as the skin of P. atrox, we have evidence for that too:
*This image is copyright of its original author
We know the jaguar doesn't have fur like that. The puma may. However, it seems Chimento and Argolin (2017) insinuate that the fur was found in association with the large remains of "F. o. mesembrina". The skull seems to be over 300 mm and of course, not puma-like, removing the puma as the owner of the fur. That leaves Smilodon as the other candidate but for the same reasons this doesn't check out.
On the point of the fossil evidence, a lack of a fossil record certainly shouldn't exclude the presence of a species, especially in warmer regions. The majority of extant species aren't recorded on fossil record for much of their range. Moreover, P. atrox was already found as far south as the Chiapas. What would stop it from continuing onward toward South America? The distance from La Brea to Chiapas isn't much difference from the distance of Chiapas to Cueva del Milodón.
The main critique of Chimento and Argolin (2017) was per Barnett's own work, he found no DNA of fossil lions. However, Barnett didn't sample "F. o. mesembrina" (no fault on him, the specimen is missing). With the small samples sizes that plague paleontology, it's a hefty jump to conclude the lack of evidence in one dataset overrides the evidence in another.
(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.speleae 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.
Reasonable points. Before we discuss further, let's make sure everyone has seen the cave painting:
*This image is copyright of its original author
To start, the reference to artwork is weak, agreed. For one, a 1.5 m cat is small for a giant lion. Jaguars can however attain these body lengths. The authors use of this point to support the presence of P. atrox is weak. However, why does the presence of a jaguar painting on a rock have to exclude the presence of another cat? We have at the least the puma and Smilodon. If we take the art literally, the puma and Smilodon never happened.
Next, a bit of conjecture and theory. We know P. spelaea and P. atrox may have overlapped ranges, indicating they did not interbreed. We also know P. atrox is primitive in form like P. fossilis (Sotnikova and Foronova 2014). Perhaps the rosettes on lion cubs represent a primitive form, and thus P. atrox had rosettes. This could explain the reproductive isolation between P. spelaea and P. atrox despite sympatry. Nonetheless, this is conjecture. To be frank, that cave art doesn't show rosettes either, just dots. Probably simplified rosettes of course, but one can hope for a South American Miracinonyx.
Back to concrete data. If we stick with the reddish-brown un-patterned fur of the cave lions as the skin of P. atrox, we have evidence for that too:
*This image is copyright of its original author
We know the jaguar doesn't have fur like that. The puma may. However, it seems Chimento and Argolin (2017) insinuate that the fur was found in association with the large remains of "F. o. mesembrina". The skull seems to be over 300 mm and of course, not puma-like, removing the puma as the owner of the fur. That leaves Smilodon as the other candidate but for the same reasons this doesn't check out.
On the point of the fossil evidence, a lack of a fossil record certainly shouldn't exclude the presence of a species, especially in warmer regions. The majority of extant species aren't recorded on fossil record for much of their range. Moreover, P. atrox was already found as far south as the Chiapas. What would stop it from continuing onward toward South America? The distance from La Brea to Chiapas isn't much difference from the distance of Chiapas to Cueva del Milodón.
The main critique of Chimento and Argolin (2017) was per Barnett's own work, he found no DNA of fossil lions. However, Barnett didn't sample "F. o. mesembrina" (no fault on him, the specimen is missing). With the small samples sizes that plague paleontology, it's a hefty jump to conclude the lack of evidence in one dataset overrides the evidence in another.
Really good points, especially pointing out the possible retention of the rosettes by P.atrox into adulthood as a form of primitive trait. However, I'm still skeptical of it due to the environment it lived in, even if we take P.fossilis as the basal species for P.atrox, the cave painting in Europe of cave lions could very easily belong to fossilis as well not necessarily only spelaea, and in that sense, those felids were not described with spots or rosettes, hence why I don't see how P.atrox could have later developed the rosettes when it lived in a open and snowy habitat where a white-tawny coat similar to those found of P.spelea would've made more sense.
As for their expansion into South America, I think if they indeed were able to go beyond Mexico in their expansion, we should in theory have no issues finding remains on different sites across Central America, especially since these lions were so big and potentially could've lived in groups. We do have fossil evidence of Smilodon across all of South America and Central America, so what would make atrox so elusive to find in terms of remains?
The fur is definitely more tricky, the researches did link it to the remains of the fossils of the felid found at the cave but what if such remains are related to a prey item that had been dragged for consumption in such cave, or was another unrelated animal together? While I don't have too much of an established opinion on the fur, I don't find it to be strong evidence for the existence of atrox in the Patagonia.
It personally seems more plausible to me that the remains in the cave for the skull and skeletons are in fact those of P.o.mesembrina and the fur got mixed into it from a different animal that could have or not had contact with said mesembrina specimen. In fact, the possibility of that fur belonging to a Mylodon or even Smilodon seems more plausible to me. But truly for now we can only speculate.
06-27-2020, 07:33 AM( This post was last modified: 06-27-2020, 07:35 AM by tigerluver )
(06-27-2020, 06:58 AM)OncaAtrox Wrote:
(06-27-2020, 06:43 AM)tigerluver Wrote:
(06-27-2020, 05:45 AM)OncaAtrox Wrote:
(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.speleae 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.
Reasonable points. Before we discuss further, let's make sure everyone has seen the cave painting:
*This image is copyright of its original author
To start, the reference to artwork is weak, agreed. For one, a 1.5 m cat is small for a giant lion. Jaguars can however attain these body lengths. The authors use of this point to support the presence of P. atrox is weak. However, why does the presence of a jaguar painting on a rock have to exclude the presence of another cat? We have at the least the puma and Smilodon. If we take the art literally, the puma and Smilodon never happened.
Next, a bit of conjecture and theory. We know P. spelaea and P. atrox may have overlapped ranges, indicating they did not interbreed. We also know P. atrox is primitive in form like P. fossilis (Sotnikova and Foronova 2014). Perhaps the rosettes on lion cubs represent a primitive form, and thus P. atrox had rosettes. This could explain the reproductive isolation between P. spelaea and P. atrox despite sympatry. Nonetheless, this is conjecture. To be frank, that cave art doesn't show rosettes either, just dots. Probably simplified rosettes of course, but one can hope for a South American Miracinonyx.
Back to concrete data. If we stick with the reddish-brown un-patterned fur of the cave lions as the skin of P. atrox, we have evidence for that too:
*This image is copyright of its original author
We know the jaguar doesn't have fur like that. The puma may. However, it seems Chimento and Argolin (2017) insinuate that the fur was found in association with the large remains of "F. o. mesembrina". The skull seems to be over 300 mm and of course, not puma-like, removing the puma as the owner of the fur. That leaves Smilodon as the other candidate but for the same reasons this doesn't check out.
On the point of the fossil evidence, a lack of a fossil record certainly shouldn't exclude the presence of a species, especially in warmer regions. The majority of extant species aren't recorded on fossil record for much of their range. Moreover, P. atrox was already found as far south as the Chiapas. What would stop it from continuing onward toward South America? The distance from La Brea to Chiapas isn't much difference from the distance of Chiapas to Cueva del Milodón.
The main critique of Chimento and Argolin (2017) was per Barnett's own work, he found no DNA of fossil lions. However, Barnett didn't sample "F. o. mesembrina" (no fault on him, the specimen is missing). With the small samples sizes that plague paleontology, it's a hefty jump to conclude the lack of evidence in one dataset overrides the evidence in another.
Really good points, especially pointing out the possible retention of the rosettes by P.atrox into adulthood as a form of primitive trait. However, I'm still skeptical of it due to the environment it lived in, even if we take P.fossilis as the basal species for P.atrox, the cave painting in Europe of cave lions could very easily belong to fossilis as well not necessarily only spelaea, and in that sense, those felids were not described with spots or rosettes, hence why I don't see how P.atrox could have later developed the rosettes when it lived in a open and snowy habitat where a white-tawny coat similar to those found of P.spelea would've made more sense.
As for their expansion into South America, I think if they indeed were able to go beyond Mexico in their expansion, we should in theory have no issues finding remains on different sites across Central America, especially since these lions were so big and potentially could've lived in groups. We do have fossil evidence of Smilodon across all of South America and Central America, so what would make atrox so elusive to find in terms of remains?
The fur is definitely more tricky, the researches did link it to the remains of the fossils of the felid found at the cave but what if such remains are related to a prey item that had been dragged for consumption in such cave, or was another unrelated animal together? While I don't have too much of an established opinion on the fur, I don't find it to be strong evidence for the existence of atrox in the Patagonia.
It personally seems more plausible to me that the remains in the cave for the skull and skeletons are in fact those of P.o.mesembrina and the fur got mixed into it from a different animal that could have or not had contact with said mesembrina specimen. In fact, the possibility of that fur belonging to a Mylodon or even Smilodon seems more plausible to me. But truly for now we can only speculate.
So actually it is not possible for currently recorded cave art to depict P. fossilis. We know this because Chauvet's art (once thought to be the world's oldest cave art) is no more than 33 kya old. This is well, well after the disappearance of P. fossilis and the split and rise of P. atrox in the west. If I give my personal bias/opinion, I agree that I imagine all the ancient lions have patternless tan fur. They were all grassland dwelling cats after all, like our modern lion. We seem to only see intricate patterns in forest species.
Next, I think Chimento and Argolin (2017) were somewhat implying we keep missing P. atrox because scientists have long since been finding any large pantherine and sticking the P. onca label on it. Moreover, species do pop up in odd places despite the lack of a fossil trail. Case in point, Uruguay's newfound S. fatalis.:
*This image is copyright of its original author
S. fatalis somehow got that far down into South America without a fossil trace in the northern parts of the continent. Strange things happen in paleontology. Off memory (so maybe I'm misremembering), but generally S. populator finds consist of a small number of bones or perhaps specimens instead of mass burials like in La Brea. This points toward unfavorable fossilization conditions (unsurprising because of the warm weather and tropical conditions) and if P. atrox was scarcer than S. populator, its fossil preservation would be even rarer.
Next, maybe S. populator and P. atrox had some geographic isolation. Here is probably the most useful Pleistocene vegetation map in existence:
*This image is copyright of its original author
*This image is copyright of its original author
Interestingly enough, the location of this "P. o. mesembrina" is around the ice sheets and temperate steppe grasslands, prime ancient lion habitat. Conversely, Smilodon finds are in warmer, dryer areas. If P. atrox established its range in the west, it would explain why fossils haven't been found in northern areas, scientists haven't really looked or found noteworthy Pleistocene assemblages. Just searching databases shows there is very little literature on Late Pleistocene assemblages in those western regions.
On the fur, Chimento and Argolin (2017) note that "Roth (1904) described in detail a piece of skin adhered to the face and to the forelimb, as well as an isolated patch of leather. The skin of the face indicates a reddish brown tone (rufous), a color that constituted the background of available skin patches from the limbs and body." Now I wish the authors could have been clearer and more explicit but it seems that the skull described is the "face" Roth is referring to. That gives some more significant connotation to the fur.
Thank you for the great discussion, always a pleasure!
(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.:
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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:
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If P.atrox is a true descendant of P.speleae 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.
Reasonable points. Before we discuss further, let's make sure everyone has seen the cave painting:
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To start, the reference to artwork is weak, agreed. For one, a 1.5 m cat is small for a giant lion. Jaguars can however attain these body lengths. The authors use of this point to support the presence of P. atrox is weak. However, why does the presence of a jaguar painting on a rock have to exclude the presence of another cat? We have at the least the puma and Smilodon. If we take the art literally, the puma and Smilodon never happened.
Next, a bit of conjecture and theory. We know P. spelaea and P. atrox may have overlapped ranges, indicating they did not interbreed. We also know P. atrox is primitive in form like P. fossilis (Sotnikova and Foronova 2014). Perhaps the rosettes on lion cubs represent a primitive form, and thus P. atrox had rosettes. This could explain the reproductive isolation between P. spelaea and P. atrox despite sympatry. Nonetheless, this is conjecture. To be frank, that cave art doesn't show rosettes either, just dots. Probably simplified rosettes of course, but one can hope for a South American Miracinonyx.
Back to concrete data. If we stick with the reddish-brown un-patterned fur of the cave lions as the skin of P. atrox, we have evidence for that too:
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We know the jaguar doesn't have fur like that. The puma may. However, it seems Chimento and Argolin (2017) insinuate that the fur was found in association with the large remains of "F. o. mesembrina". The skull seems to be over 300 mm and of course, not puma-like, removing the puma as the owner of the fur. That leaves Smilodon as the other candidate but for the same reasons this doesn't check out.
On the point of the fossil evidence, a lack of a fossil record certainly shouldn't exclude the presence of a species, especially in warmer regions. The majority of extant species aren't recorded on fossil record for much of their range. Moreover, P. atrox was already found as far south as the Chiapas. What would stop it from continuing onward toward South America? The distance from La Brea to Chiapas isn't much difference from the distance of Chiapas to Cueva del Milodón.
The main critique of Chimento and Argolin (2017) was per Barnett's own work, he found no DNA of fossil lions. However, Barnett didn't sample "F. o. mesembrina" (no fault on him, the specimen is missing). With the small samples sizes that plague paleontology, it's a hefty jump to conclude the lack of evidence in one dataset overrides the evidence in another.
Really good points, especially pointing out the possible retention of the rosettes by P.atrox into adulthood as a form of primitive trait. However, I'm still skeptical of it due to the environment it lived in, even if we take P.fossilis as the basal species for P.atrox, the cave painting in Europe of cave lions could very easily belong to fossilis as well not necessarily only spelaea, and in that sense, those felids were not described with spots or rosettes, hence why I don't see how P.atrox could have later developed the rosettes when it lived in a open and snowy habitat where a white-tawny coat similar to those found of P.spelea would've made more sense.
As for their expansion into South America, I think if they indeed were able to go beyond Mexico in their expansion, we should in theory have no issues finding remains on different sites across Central America, especially since these lions were so big and potentially could've lived in groups. We do have fossil evidence of Smilodon across all of South America and Central America, so what would make atrox so elusive to find in terms of remains?
The fur is definitely more tricky, the researches did link it to the remains of the fossils of the felid found at the cave but what if such remains are related to a prey item that had been dragged for consumption in such cave, or was another unrelated animal together? While I don't have too much of an established opinion on the fur, I don't find it to be strong evidence for the existence of atrox in the Patagonia.
It personally seems more plausible to me that the remains in the cave for the skull and skeletons are in fact those of P.o.mesembrina and the fur got mixed into it from a different animal that could have or not had contact with said mesembrina specimen. In fact, the possibility of that fur belonging to a Mylodon or even Smilodon seems more plausible to me. But truly for now we can only speculate.
So actually it is not possible for currently recorded cave art to depict P. fossilis. We know this because Chauvet's art (once thought to be the world's oldest cave art) is no more than 33 kya old. This is well, well after the disappearance of P. fossilis and the split and rise of P. atrox in the west. If I give my personal bias/opinion, I agree that I imagine all the ancient lions have patternless tan fur. They were all grassland dwelling cats after all, like our modern lion. We seem to only see intricate patterns in forest species.
Next, I think Chimento and Argolin (2017) were somewhat implying we keep missing P. atrox because scientists have long since been finding any large pantherine and sticking the P. onca label on it. Moreover, species do pop up in odd places despite the lack of a fossil trail. Case in point, Uruguay's newfound S. fatalis.:
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S. fatalis somehow got that far down into South America without a fossil trace in the northern parts of the continent. Strange things happen in paleontology. Off memory (so maybe I'm misremembering), but generally S. populator finds consist of a small number of bones or perhaps specimens instead of mass burials like in La Brea. This points toward unfavorable fossilization conditions (unsurprising because of the warm weather and tropical conditions) and if P. atrox was scarcer than S. populator, its fossil preservation would be even rarer.
Next, maybe S. populator and P. atrox had some geographic isolation. Here is probably the most useful Pleistocene vegetation map in existence:
*This image is copyright of its original author
*This image is copyright of its original author
Interestingly enough, the location of this "P. o. mesembrina" is around the ice sheets and temperate steppe grasslands, prime ancient lion habitat. Conversely, Smilodon finds are in warmer, dryer areas. If P. atrox established its range in the west, it would explain why fossils haven't been found in northern areas, scientists haven't really looked or found noteworthy Pleistocene assemblages. Just searching databases shows there is very little literature on Late Pleistocene assemblages in those western regions.
On the fur, Chimento and Argolin (2017) note that "Roth (1904) described in detail a piece of skin adhered to the face and to the forelimb, as well as an isolated patch of leather. The skin of the face indicates a reddish brown tone (rufous), a color that constituted the background of available skin patches from the limbs and body." Now I wish the authors could have been clearer and more explicit but it seems that the skull described is the "face" Roth is referring to. That gives some more significant connotation to the fur.
Thank you for the great discussion, always a pleasure!
This clears a lot of doubts regarding my previous post, so I'm more open about the idea of such remains belonging to P.atrox. Hopefully we will get more detailed scientific papers on the matter in the near future as this remains a rather controversial topic, but topics like these are what keep paleobiology so intriguing and fascinating.
I have a question. This chap Panthera gombaszoegensis, commonly known as the European Jaguar, was a proper Jaguar or something we call Jaguar like Cave lion and is incorrectly termed as lion?
@Rishi based on my knowledge, P. gombaszoegensis was the basal species that crossed the Beringia bridge into the America's and later diversified into the jaguar. Some refer to it as an primitive version of a jaguar and it presented characteristics that would put it in between a lion and jaguar morphologically speaking, which makes sense as lions and jaguars are each other's closest relatives.
Those specific models you posted are based on a conceptual art in which P. gombaszoegensis is depicted more closely aligned to the lion lineage than the jaguar's.
@Rishi there isn't an overall consensus on which one is closest to jaguar, the lion or leopard, but based on the morphology of P. gombaszoegensis it seems to me that there is more reason to suggest it's the lion as it shared characteristics with both P. onca and P. leo, hence why the artist you posted made the sketches of P. gombaszoegensis more similar to those of a lion.
P. gombaszoegensis would sit behind the jaguar and lion clade, maybe besides the leopard, but that is just a wild guess of mine.
