A lot is known about the ancient lions and tigers, but jaguars have a very intriguing fossil record as well. In here we are to post information and new discoveries regarding ancient jaguar species and subspecies.

---

Skull:






"Body Mass estimation. The size of the m1 in the felid is the classic best gauge of body mass (Legendre and Roth, 1988, VanValkenburgh, 1990). We calculated the body mass (BM) of F. o. mesembrina using the m1 measurements, following the proposal of VanValkenburgh (1990) with the formula:




We determinated a body mass of 231.21 kg for “Panthera onca mesembrina”. This value is well within of the range of the males of Panthera atrox (Wheeler and Jefferson, 2009), whereas the values are much smaller in Panthera onca (Christiansen and Harris, 2005, Prevosti and Vizcaíno, 2006). Further, this body mass is within the range of largest felids, such as Smilodon fatalis and S. populator (Christiansen and Harris, 2005).

Recently, Prevosti and Martin (2014) made a mass calculation of “P. onca mesembrina” based on some unpublished fossil remains. They obtained values between 190 kg to 243 kg, based on the length of m1 of different individuals (see Prevosti and Martin, 2014: Supplementary data 1). It is worth mentioning that the living P. onca shows values near 100 kg (102 kg sensu Sunquist and Sunquist, 2002), and exceptionally upper values of 158 kg (Seymour, 1989). Further, the large extinct North American jaguar P. onca augusta, was 15 to 20% larger than living jaguar, being less than 190 kg (Seymour, 1989).

In this way, the mass calculation for “P. o. mesembrina” obtained by Prevosti and Martin (2014) and present paper points that the Patagonian Panthera was a felid that duplicates the size of living or extinct jaguars.

Additionally, based on body mass determination, it is possible to calculate the focused prey size of “P. o. mesembrina” on the basis of the following formula (Hemmer, 2004):



"
Source: https://www.sciencedirect.com/science/ar...8317301094

*This image is copyright of its original author

Reconstruction by Roman Uchytel

Surprised there wasn't already a thread on these cool pleistocene cats. Not quite cheetahs and not quite pumas, these cats had a lean morphology quite (but not exactly) like the cheetahs of africa. It is thought they are the reason pronghorn antelopes are as fast as they are today. Here is some literature on this cat below. Opinions differ as to its evolution, taxonomy, ecology and relation to actual cheetahs as they were named after. Important to note that they were not just plains animals, also inhabiting rocky mountainous areas likely preying upon goats like modern day snow leopards. I also think this thread is useful as to compare and contrast the morphology of modern day cheetahs, snow leopards and pumas, a topic I've briefly seen discussed around the forum (one may question the inclusion of snow leopards, I mention them due to the mention of their similar morphology to cheetahs in "Big Cats and Their Fossil Relatives". Strip down the fur and they're not so different)

Adams, D. 1979. The Cheetah: Native American. Science. 205:1155-1158
Barnett, R., Barnes, I., Phillips, M., 

Martin, L., Harington, C., Leonard, J., Cooper, A. 2005. Evolution of the extinct sabretooths and the American cheetah-like cat. Current Biology. 15, 15:  R589-90

Hodnett, J., Mead, J., White, R., Carpenter, M.  2010. Miracinonyx trumani (Carnivora: Felidae) from the Rancholabrean of Grand Canyon, Arizona and its implications for he ecology of the “American cheetah”,  in Program and Abstracts, Journal of Vertebrate Paleontology, 30:sup2, 1A-198A

Kennedy, N., Bhatt, R. 2012. A geometric and kinematic backbone model of the cheetah, Acinonyx jubatus, and its application to understanding the spinal kinematics of Miracinonyx trumani, in Programs and Abstracts, Journal of Vertebrate Paleontology

Martin, L., Gilbert, B., Adams, D. 1977. A cheetah-like cat in the North American Pleistocene. Science. 195: 981-982

Van Valkenburgh, B., Grady, F., Kurten, B. 1990. The Plio-Pleistocene cheetah-like cat Miracinonyx inexpectatus of North AmericaThe Plio-Pleistocene cheetah-like cat Miracinonyx inexpectatus of North AmericaThe Plio-Pleistocene cheetah-like cat Miracinonyx inexpectatus of North America. Journal of Vertebrate Paleontology. 10,4 : 434-454

Walker, D. 2000. Pleistocene and Holocene records of Antilocapra americana: A review of the FAUNMAP dataPleistocene and Holocene records of Antilocapra americana: A review of the FAUNMAP dataPleistocene and Holocene records of Antilocapra americana: A review of the FAUNMAP data. Plains Anthropologist. 45, 174, 32: 13-28

I'll be reading these in the coming months and posting parts I find interesting, feel free to do the same and more!

Since there are a lot of species outside of felids and canids, which have interesting and sometimes really impressive conflicts/confrontations, this thread can be used to highlight those from other postings.

I start this one with two alligators. Very interesting to hear sounds even though a short clip. Btw... also when talking about bite forces, we don´t see head crushing here. I point this out because so often people talk about "superior bite forces", here once again it can be seen, that some theoretical or even proven bite force, when biting something with a really good bite and not too thick object isn´t quite the same as situation is when bite isn´t perfect. I really don´t think, that crocodiles can bite so hard, when object is mostly there, where animals usually have canines, with crocodiles it could be said, that when in frontal part of jaws. 

Starting a thread for landforms which I'm sure always or regularly catch your attention if you are nearby, with a post about the highest of them all on Earth: Mount Everest

With air pollution levels down during the pandemic, Kathmandu photographer Abhushan Gautam captured a sight that has been shrouded in the city's smog for nearly 50 years — a clear view of Mount Everest: https://www.cbc.ca/radio/asithappens/as-...-1.5580607, https://thehill.com/changing-america/sus...-120-miles

   
   
   

Istock: 
   

Post anything about Kevin Richardson and his lions.

*This image is copyright of its original author

Here is a video of him with Gandalf, Cussasa and Sibindie

So, as the sons of Birmingham males coming to an age of adulthood, i think its time that they have a thread for themselves for posting about them. 

Theres currently 3 males that are reaching adulthood, Nkuhuma, Torchwood and Styx young males:

Nkuhuma young male:




He is few months short of 4 yrs old, he is the oldest of the 3, other 2 are few months younger. 

Torchwood young male:




Styx young male:




All 3 males are alone, without coalition partners atm, while Styx and Torchwood males are still with their natal prides (no dominant males to oust them), Nkuhuma male wasn't that lucky, he is living tough nomadic life for almost a year now (ousted by N. Avocas). It will be interesting to see what the future holds for this 3 males.

Besides them, theres multiple subadult male sons (correct number still unknown, but a lot of them) in Kambula pride, and their future seems bright with protection from theirs strong fathers and mothers:

Giganotosaurus roseae was a giant carcharodontosaurid theropod from the early Late Cretaceous (late Cenomanian to early Turonian stage) of what is now Argentina. 
Just like some of its more famous relatives, G. roseae was one of the largest known theropods, with known specimens indicating an animal substantially heavier than Tyrannosaurus rex and very similar in size to the closely related Giganotosaurus carolinii. This species is commonly considered to be its own genus (Mapusaurus), but because this generic separation is based almost entirely on elements that the G. carolinii holotype does not preserve (making a proper judgement on almost all proposed differentiation between the 2 impossible), with the only differences noted in overlapping material being a less pneumatic quadrate and differently rugose nasals in G. roseae, Mapusaurus being a valid genus remains highly improbable unless a specimen of G. carolinii is discovered proving G. roseae to be generically distinct.
Coria and Currie (2006) note the majority of possible adult specimens known are comparable in size to the G. carolinii holotype MUCPv-Ch1 (suggesting these G. roseae individuals were around 12.4 meters in length and 8320 kg), although not with the same exact proportions, having taller and wider neural spines, a more elongate fibula (101 centimetres compared to 98.5 centimetres) but more slender (81-89% the width as in MUCPv-Ch1) and with a differently proportioned skull that was deeper relative to its length. 
Considering this, a fragmentary maxilla is coherent with the size of the MUCPv-Ch1-sized individual (MCF-PVPH-108.169). A neural arch from an axis (MCF-PVPH-108.83) and a scapular blade fragment are also the same exact size as the same elements in MUCPv-Ch1.
Moreover (contrary to popular belief), these aren't the largest remains from the bonebed - a pubic shaft (MCF-PVPH-108.145) 10% larger than that of MUCPv-Ch1 suggests a maximum size of 13.6-13.7 meters long and 11100 kg. Some tibiae (MCF-PVPH-108.68-73) also suggest very large sizes of roughly 12.7-13.2 meters long and 8950-9880 kg.
The remains of G. roseae were discovered in a bone bed containing at least seven individuals of various growth stages. Since the bonebed's discovery and first report in 1997, researchers have speculated that this may represent gigantic theropods practicing pack-life (similar to modern carnivores like wolves and lions) and may provide clues about the behavior of this species. 
Paleontologist Rodolfo Coria, contrary to his published article, repeated in a press-conference the aforementioned earlier suggestions that this congregation of fossil bones may indicate that G. roseae hunted in groups and worked together to take down large prey, like the gigantic sauropod Argentinosaurus. If so, this would be the first substantive evidence of gregarious behavior by large theropods other than tyrannosaurids and Allosaurus, although whether they might have hunted in organized packs (as wolves do) or simply attacked in a mob, is unknown.

I have seen good viral videos on social media platform like facebook, twitter, instagram etc..

Post, those videos in this thread linking to original source, giving proper credit.

I will start with this awesome videos, were a fox tried to steal the food of an eagle but ends up bitter.

Click to play

Carcharodontosaurus is a genus of carnivorous carcharodontosaurid dinosaur that existed during the Cenomanian stage of the mid-Cretaceous period. It is currently known to have been among the largest theropods found, with known specimens significantly larger than Tyrannosaurus rex and on par with or approaching the estimated body mass for Giganotosaurus and Spinosaurus. 
The genus Carcharodontosaurus is named after the shark genus Carcharodon. itself composed of the Greek karchar[os] ( meaning "jagged" or "sharp") and odōn ("teeth"), and the suffix -saurus ("lizard"). Carcharodontosaurus includes some of the longest and heaviest known carnivorous dinosaurs, with various scientists proposing length estimates for the species. Based on relatives such as Giganotosaurus, the neotype of Carcharodontosaurus (SGM-DIN 1) would have been roughly 13-13.7 meters long and 9000-9800 kg. But this specimen was only a subadult, so adults would have been even larger.
Carcharodontosaurus were carnivores, with enormous jaws and sharp, serrated teeth (just like those of sharks, hence the same) up to 20 cm long. A skull length of over 1.6 meters has been restored for C. saharicus. In 2001, Hans C. E. Larsson published a description of the inner ear and endocranium of Carcharodontosaurus saharicus. Starting from the portion of the brain closest to the tip of the animal's snout is the forebrain, which is followed by the midbrain. The midbrain is angled downwards at a 45-degree angle and towards the rear of the animal. This is followed by the hindbrain, which is roughly parallel to the forebrain and forms a roughly 40-degree angle with the midbrain. 
Overall, the brain of C. saharicus would have been similar to that of a related dinosaur, Allosaurus fragilis. Larsson found that the ratio of the cerebrum to the volume of the brain overall in Carcharodontosaurus was typical for a reptile. Carcharodontosaurus also had a large optic nerve.

Giganotosaurus is a species of allosauroid theropod dinosaur that lived in what is now Argentina during the early Cenomanian age of the Cretaceous period, approximately 98 to 97 million years ago. The holotype specimen was discovered in the Candeleros Formation of Patagonia in 1993, and is almost 70% complete. The animal was named Giganotosaurus carolinii in 1995; the genus name translates as "giant southern lizard" and the specific name honours the discoverer, Rubén D. Carolini. A dentary bone, a tooth and some tracks, discovered before the holotype, were later assigned to this animal. The genus attracted much interest and became part of a scientific debate about the maximum sizes of theropod dinosaurs.
Giganotosaurus was one of the largest known terrestrial carnivores ever. The most complete specimen and also the holotype, MUCPv-Ch1, is thought to be 12.4 meters in length and weigh more than 8320 kg. The referred dentary MUCPv-95 that appears to have been an animal 10% larger has been used to extrapolate a length of 13.6-13.7 meters and a weight of more than 11100 kg, the average size of the 2 specimens being about 13.1 meters in length and more than 9700 kg in weight. Some researchers have found the animal to be larger than Tyrannosaurus. 
The skull was very deep, with rugose (rough and wrinkled) nasal bones and a ridge-like crest on the lacrimal bone in front of the eye. The front of the lower jaw was flattened, and had a downwards projecting process (or "chin") at the tip. The teeth were compressed sideways and had serrations. The neck was strong and the neural spines tall.
Part of the family of theropods known as the Carcharodontosauridae, Giganotosaurus is one of the most completely known members of the group, which includes other very large theropods, such as the closely related Carcharodontosaurus and sister species Giganotosaurus roseae. Giganotosaurus is thought to have been homeothermic (a type of "warm-bloodedness"), with a metabolic rate between that of a mammal and a reptile, which would have enabled fast growth. It may have been relatively fast moving, with a calculated maximal running speed of 14 metres per second (50.4 km/h). It would have been capable of closing its jaws quickly, capturing and bringing down prey by delivering powerful bites. The "chin" may have helped in resisting stress when a bite was delivered against prey. Giganotosaurus is thought to have been the top predator of its ecosystem, and it may have fed on herbivorous dinosaurs such as sauropods or ornithopods.