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Pleistocene Big Cats
The Cave Lion (Panthera spelaea and Panthera fossilis)
The Cave Lion (Panthera spelaea and Panthera fossilis)
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The Cave Lion (Panthera spelaea and Panthera fossilis)
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The supposedly younger Panthera fossilis didn't outlast its predecessor Panthera spelaea.
Or maybe Panthera fossilis didn't directly derive from Panthera spelaea, but from a later group of migrant? The newcomer Panthera fossilis used to dominate over Panthera spelaea with its superior body size. After the extinction of Panthera fossilis, Panthera spelaea finally ascending into a higher position in the food chain and thrived into a greater body size like Panthera fossilis.  Panthera shawi
In this post, I'll go over the scant record of Panthera shawi, an old fossil "lion."The species was first recorded in 1948 in the manuscript Some South African pliocene and pleistocene mammals. Broom recorded a large canine from Bolt's farm near Sterkfontein, South Africa, which is dated to about 2.9 mya-4.5 mya.  *This image is copyright of its original author In 1956, Ewar found some more specimens presumed to be of the same species in Kromdraai (around 2 mya old) and Swartkrans (also 2 mya old). Both these sites are also in South Africa. Ewar believed that the Swartkrans specimen was too small to be P. shawi, but that theory I do not agree with due to variation between genders and individuals.  *This image is copyright of its original author  *This image is copyright of its original author In the 1980s, Turner (1986 and 1987) logged 3 more specimens as plain lions from Sterkfontein Member 4 (2.6-2.0 mya old). In all likelihood, these were P. shawi and not P. leo.  *This image is copyright of its original author  *This image is copyright of its original author P. shawi was very large. Starting with the strongest predictor of size, the distal humerus that measures 111.9 mm in length exceeds the corresponding measurement of the largest P. atrox humerus that measured 409 mm and and just exceeds the width of a very robust 396 mm P. atrox humerus as well. Moving on to the dentition, the Broom canine's width is similar to the canines found in 400 mm-420 mm P. atrox skulls. The Ewar Kromdraai ca. 40 mm sup. P4 (Ewar mentioned that the full tooth could have been a smidge larger than 40 mm) is quite large, but the skull could've ranged from only 410 mm in length to 470 mm in length based on a collection of P. atrox and P. spelaea data (this refers back to the weakness of dentition when estimating body size). The other Ewar Kromdraai sup. P3 and inf. P3 would give the same skull size ranges. The 30 mm M1 could have been of a specimen with a skull around 390-440 mm. The Ewar Startkrans dentition are from skulls well below 400 mm in all likelihood. The Turner teeth are of specimens even smaller. The above analysis indeed shows a big cat, likely on average the size of a very large lion or tiger, indicating the maximum would have been quite, quite large.
I think Panthera shawi is indeed the source of those late lion species such as Panthera spelaea/Panthera fossilis/Panthera atrox/Panthera leo.
Now I hypothesize that Panthera spelaea is likely the first offshoot that split off from Panthera shawi in about 2 million years ago, then followed by Panthera fossilis in about 1 million years ago. Although Panthera fossilis went full extinction in the late Pleistocene, but it is believed that the remaining Panthera fossilis population had evolved into Panthera atrox. Finally, the leftover population of Panthera shawi in Africa had eventually evolved into Panthera leo, and it didn't migrate out of Africa until 100,000 years ago.
PS, after solving the genetic puzzle between Panthera spelaea and Panthera fossilis, it is very likely that Panthera fossilis will turn out to be the younger species.
Now I am just wondering if Panthera fossilis was an offspring of Panthera spelaea or just descended from the second wave of lion migration that was not directly related to Panthera spelaea?
It's interesting to note that P. shawi is from South Africa, thousands of miles away from where the cave lion stem group would have migrated from. While a continuous population of lion-stem group in Africa is likely, P. shawi must have still become somewhat distinct from the cave lion stem due to allopatric, spatially-produced speciation.
Back to the P. spelaea-P. fossilis issue. One option is that we stick to what the Barnett et al. (2016) proposed and stick P. fossilis into the P. spelaea branch directly as follows:  *This image is copyright of its original author The support for this approach would be that that there is a clear chronological distinction between the two cave lion forms in fossil record, thus leaving the option that P. s. fossilis (as described by this theory) was the earlier P. spelaea signified by the light blue branch which in time morphed into P. spelaea spelaea (signified by the indigo branch) as proposed by Marciszak et al. (2014). The assumption this theory makes is that we have not missed any P. spelaea spelaea specimens that predate or are contemporary to P. fossilis. It also assumes that P. fossilis is genetically not much different than P. spelaea and can safely be placed as a species on the P. spelaea evolutionary branch. The second assumption is what meets adversity. There is clear morphological distinction between the skulls of P. fossilis and P. spelaea. One would assume that morphological differences warrant genetic differences, thus affecting the above phylogenetic tree. Sotnikova and Foronova (2014), Sotnikova and Nikoskyi (2006), and Hanko and Korsos (2007) believe the morphological differences are hefty enough to warrant speciation, while Marciszak et al. (2014) takes these difference as subspecific. If P. atrox, which is similar to P. fossilis according to Sotnikova and Foronova (2014) is by consensus considered a distinct species from P. spelaea, than it would make most sense to treat P. fossilis the same. I modified the phylogenetic tree to observe different options. Disclaimer, this is all very crude and some movements may not be yet supported by the genetic data. If we go with P. fossilis as distinct, we could modify the phylogeny in this way:  *This image is copyright of its original author This would indicate three branching from the stem group. We could stick P. fossilis as an earlier branch as follows:  *This image is copyright of its original author Neither model is supported by fossil record, but that could just attributed to a lack of data. Nonetheless, as it stands, neither model can validated until we find older P. fossilis specimens or DNA test the specimens we do have. Another phylogenetic modification could be using the Sabol (2011) hypothesis.  *This image is copyright of its original author For such a model, the confidence intervals have to respected the emergence dates shifted within the confidence interval range. As the new emergence date of P. spelaea would still be within the 95% CI, this would not be a completely invalid model. This model would also incorporate Hanko and Corsos' (2007) that P. fossilis was closer to P. leo than P. spelaea is to P. leo. Based on the chronological fossil record and the aforementioned studies that do give convincing reason that P. fossilis and P. spelaea are not exactly a chronological product of the same lineage, this last model may be the most accurate.
Based on the genetic evidence, Panthera spelaea was older than Panthera fossilis, but based on the current available fossils, it was younger. Unless we could find the older fossil record of Panthera spelaea.
@tigerluver, if you are leaning more toward the proposed model by Hanko and Corsos' (2007), then do you think it is ok to place the fossilis branch closer toward the leo branch? How about fossilis and leo in the same branch with fossilis split from leo approximately 1 mya? As for spelaea, we already know it split from leo approximately 2 mya, and now we are just waiting for the discovery of its older fossil evidence.
That's a good idea as well and still fits Hanko and Korsos' (2007) theories that P. fossilis is both distinct and also more closely related to the lion.
 *This image is copyright of its original author Also, Barnett et al. (2016) aren't saying P. spelaea are older than P. fossilis, they are saying that P. fossilis is P. spelaea and should happen somewhere on that branch as in the first figure in post #20.
The fossil record of Panthera fossilis was much older, thus it is also much harder to extract its DNA sample.
So here is the remaining puzzles need to be solved: 1. Panthera spelaea and Panthera fossilis, which one is older? 2. If Panthera spelaea was not as old as it suggests, then we still need to find the missing link up to 2 million years ago where its ancestral form that split off from Panthera leo. As for the model of Hanko and Korsos' (2007), you can also add the atrox branch within the fossilis branch, and split from the main fossilis branch approximately 400 kya. I assume that Panthera atrox might be evolved from the Asian branch of Panthera fossilis.
The P. atrox point is probably right according to Sotnikova and Foronova (2014) paper.
For the questions, I think we need to remember that the two P. spelaea specimens/subspecies tested by Barnett et al. (2016) have their most recent common ancestor split only 500 kya. It is the cave lion "stem" group that split 1.89 mya, which is not genetically identical to the most recent form of P. spelaea as the phylogenetic tree shows. This keeps open the possbility of the following evolution: Cave lion stem group (1.89 mya) -> P. (spelaea?) fossilis (1 mya) -> P. spelaea spelaea 500 kya So there must be a stem group somewhere out there in the connection between Africa and Eurasia that dates to about 2 mya.
So this means that spelaea/fossilis/atrox still share a common ancestor within the Cave lion stem group.
It was their common ancestor that split off from the main branch of Panthera shawi in Africa, not Panthera spelaea itself.
Fossilized Panthera spelaea.
 *This image is copyright of its original author  *This image is copyright of its original author Fossilized Panthera leo.  *This image is copyright of its original author  *This image is copyright of its original author
A new "American lion" skeleton discovered in Alaska that dated back to the late Pleistocene, but I guess this should be de facto a Beringian Cave lion.
http://www.dinolandplus.com/animal-index/view/category/lions
I think this could be the result of the arisen human-lion conflict, and the dead body of the lion could be considered as exploitable when everything was in shortage.
Extinct lion cubs found in Siberia are up to 55,000 years old - latest test results reveal
By The Siberian Times reporter03 November 2016 Tantalising studies now underway to establish if one of two carcases preserved by permafrost has traces of world's oldest mother's milk. New research indicates they are at least twice as old, living between 25,000 and 55,000 years ago, with one of them 'perfectly' preserved. Picture: Vera Salnitskaya  *This image is copyright of its original author The lion cubs found in summer 2015 were previously believed to be at least 12,000 years old. But new research indicates they are at least twice as old, living between 25,000 and 55,000 years ago, with one of them 'perfectly' preserved. These cave lion siblings - which became extinct around 10,000 BC - were between one and two weeks old when they were killed in a likely prehistoric ceiling collapse in their den. Intriguingly, the tails of the ancient cubs were short compared with modern lions - 23% of their body length compared with 60%. Scientists have now established the cubs - named Uyan and Dina- were found in Edoma permafrost deposits formed during the Karginskii interstadial, a warmer period late in the Ice Age from 25,000 to 55,000 years ago. The scientists want to extract all possible knowledge but at the same time cause 'minimum damage to the ancient cave lion'. Pictures: Vera Salnitskaya  *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 Dr Albert Protopopov, one of the main researchers, said: 'That means that the cubs were not younger than 25,000 years old. Previously the youngest date for the cubs was 12,000, the time when the cave lions become extinct.' The 'exact data' on their age will be calculated later. 'The analysis is not finished yet,' he said. 'As for their age when they died - we think that they were 1 to 2 weeks old. 'We made a CT scan and saw that their teeth had not appeared yet. Based on a comparison with African lions, we concluded that they were younger than one month, most likely between 1 and 2 weeks old.' Dr Protopopov, head of the Department of Mammoth Fauna, Academy of Sciences of the Sakha Republic (Yakutia), said: 'The CT scan also helped us to check the state of the inner organs of cubs. Dr Albert Protopopov, one of the main researchers, said: 'That means that the cubs were not younger than 25,000 years old.' Picture: Vera Salnitskaya  *This image is copyright of its original author 'One of cubs, Uyan, is more preserved and the CT showed us that there is something in its stomach. Now we are discussing between us: what is it - mother's milk or some other substance.' The 'opaque white fluid' might be milk but could also be gastric fluid. The scientists want to extract all possible knowledge but at the same time cause 'minimum damage to the ancient cave lion. 'With the milk, it is very interesting, but we need to think twice before doing something,' he said. 'The finds are really unique and any reckless action by us can damage them. We think that that perhaps we can use some unobtrusive method to research the cub's stomach.' DNA analysis confirms the cubs are cave lions but they hope for better quality analysis when samples are taken from internal organs. 'We also plan to conduct radioisotope analysis to learn about their environment, what did they eat and what is more important - what did their mother eat and from where she came,' he said. 'We plan to make another more powerful CT scan to get more detailed information about their intestines.' South Korean cloning guru Hwang Woo-suk took is believed to have taken samples from one of the cubs. Pictures: Galina Mozolevskaya/YSIA  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author The cubs were dug last year from their icy grave 'complete with all their body parts: fur, ears, soft tissue and even whiskers', said Dr Protopopov. South Korean cloning guru Hwang Woo-suk took is believed to have taken samples from one of the cubs, found close to the Uyandina River. He is also hoping to clone the extinct woolly mammoth. Cave lions - Panthera spelaea (Goldfuss) - lived during Middle and Late Pleistocene times on the Eurasian continent, from the British Isles to Chukotka in the extreme east of Russia, and they also roamed Alaska and northwestern Canada. Research on the two cubs could help to explain why the species died out, since the animal had few predators, was smaller than herbivores, and was not prone to getting bogged down in swamps, as did woolly mammoths and rhinos. One theory is that they were hunted for their skins by ancient man. The cubs were found in Abyisky district, on the bank of the Uyandina River, in 57 kilometres from Belaya Gora village. Pictures: The Siberian Times, Vera Salnitskaya  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author The latest results of research on the cubs were presented at the recent annual meeting of the Society of Vertebrate Paleontology in Salt Lake City. Research was conducted by scientists from Russia and the US, namely the Yakutian Academy of Sciences, Yakutsk; the Diamond and Precious Metals Geology Institute, Russian Academy of Sciences, Yakutsk; the Institute of Human Morphology, Russian Academy of Medical Sciences, Moscow; the Borissiak Paleontological Institute, Russian Academy of the Sciences, Moscow; the Mammoth Site of Hot Springs, Hot Springs, South Dakota; and the University of California Santa Cruz, Santa Cruz, California. |
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