Posts Tagged ‘Panthera leo’

2 New Studies of Pleistocene Lions

January 6, 2019

There were 3 species of lions living on earth during the late Pleistocene.  The African lion (Panthera leo) is the only species still extant.  The cave lion (P. spelaea) ranged across Eurasia from Britain to Beringia which included Alaska and Yukon above the Canadian Ice Sheet.  The giant American lion (P. atrox) lived in North America south of the Ice Sheet from California to Florida.  Some taxonomists formerly thought the 3 lions were the same species, but recent analysis of anatomy and genetics determined they were 3 distinct species.

2 new studies of Pleistocene lions were published last year.  The first study described an unusually large lion skull found in Natodermi, Kenya.  This specimen is estimated to be 196,000 years old. On average cave lions and giant American lions were larger than African lions.  P. atrox was the largest species of lion, averaging 25% larger than African lions, and 1 specimen is estimated to have weighed over 1000 pounds.  (See https://markgelbart.wordpress.com/2017/01/31/panthera-atrox-the-1007-pound-giant-lion/ )   However, the specimen described in this new paper (catalogued as #KNM-ND59673) belonged to an individual that may have been larger than any cave lion specimen ever described and even larger than all but 2 known American lion specimens.  The size comparison estimates in this paper were based on dental dimensions.  The authors of this paper believe this individual was part of an extinct population that grew to a larger size because they hunted an extinct species of large buffalo (Syncerus antiquus).  They think it was a subspecies of African lion related to the ancestors of the 2 regional haplotypes of lion that still occur today.  Genetic evidence suggests northern lions diverged from an ancestral population of lions 147,000 years ago, while southern lions diverged 189,000 years ago.  This specimen was found on the border between the 2 modern haplotypes.  Although they don’t think it was a distinct species, they can’t completely rule it out–there just isn’t enough evidence.  It seems likely some Pleistocene African lions were just as large as the other 2 species.  Lions originally evolved in Africa but fossil evidence from that continent is more rare than in Eurasia and North America.

 

196,000 year old African lion skull.

Image result for syncerus antiquus

Pleistocene lions may have grown larger in Africa to help them bring down this large extinct species of buffalo.

The 2nd study described 4 specimens of cave lion found in Medvedia Cave located in the Zapadne Tatry Mountains.  These mountains border northern Slovakia and southern Poland. Referring to this species as the “cave” lion is misleading.  Most individuals never went inside a cave during their entire life.  A cave environment is just 1 of the rare places where their remains could be preserved.  Medvedia Cave is the highest altitude that a lion fossil has ever been found.  The authors of this paper think lions searched through caves for hibernating bears, and groggy bears may have been an important part of high altitude lions’ diets because other substantial prey was scarce here.  Some scientists think cave lions were solitary hunters or perhaps hunted in pairs, unlike social African lions that live in large prides.  I disagree with this notion.  Adult male lions grow too large and bulky to hunt prey effectively, and they depend upon females to bring them food.

Lions were more widespread during the Pleistocene because human populations were sparse.  Humans have outcompeted lions since then.  If not for the rise of humans, lions would still be just as widespread as they used to be.

Reference:

Manth, F. ; et. al.

“Gigantic Lion, Panthera leo, from the Pleistocene of Natodermi, eastern Africa”

Journal of Paleontology 92 (2) Novemeber 2018

Sabol, Martin; Juraj Gullar and Jan Harrat

“Montane Record of the Late Pleistocene Panthera spelaea (Goldfuss 1810) from Zapadne Tatry Mountains (northern Slovakia)”

Journal of Vertebrate Paleontology  38 (3) 2018

See also: https://markgelbart.wordpress.com/2016/01/07/uf9076-a-complete-skull-and-jaws-of-a-giant-lion-panthera-atrox-found-in-the-ichetucknee-river-florida/

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A New Study of Pleistocene Lion (Panthera spelaea) Genetics Confirms it was a Distinct Species

August 29, 2016

A couple of my readers brought 2 new studies of lion genetics to my attention.  One of the studies confirms the notion that the extinct Eurasian lion (Panthera spelaea) was a distinct species from the present day African lion (Panthera leo).  (See: https://markgelbart.wordpress.com/2012/05/02/three-pleistocene-lions-were-they-distinct-species-or-the-same-animal/ ) The scientists who co-authored this study analyzed the DNA from 2 ~30,000 year old specimens of “cave” lions and used it to compare with the DNA of other felid species.  They extracted the DNA from a lion arm bone found in Yukon, Canada and some lion hair preserved in Siberian permafrost.  The study suggests Panthera spelaea and P. leo were sister species that diverged ~1.89 million years ago.  This divergence precedes the oldest known lion fossil by over 1 million years.  Panthera fossilis, an extinct archaic species of lion, was thought to be ancestral to both P. spelaea and P. leo.  However, this species lived 700,000 years ago, and the divergence likely occurred before P. fossilis evolved.  Fossils of a cat in the panthera genus that date to 3.5 million years ago have been found in Africa, but not enough skeletal evidence exists to narrow it down to species level.  P. spelaea certainly evolved a greater physiological adaptation to colder climates at the beginning of the Pleistocene as periodic Ice Ages became more severe in Eurasia.  This physiological difference may explain the speciation event that separated P. spelaea from P. leo.

Although this study didn’t examine Panthera atrox, the species of lion that occurred across North America south of the Cordilleran Glacier, the results do make it seem more likely that it too was a different species.

Specimens used in the below referenced study–a lion arm bone found in the Yukon and a hair sample found in Siberian permafrost.

The other study looked at the genetics of present day lions living in Africa and India.  This study determined there are 6 distinct regional breeding populations of lions–the west, central, northwest, northeast and south Asian, east/southern, and southwest.  These breeding populations have been repeatedly isolated from each other because of altered landscapes influenced by cyclical Pleistocene climate changes.  Lions prefer open savannah habitats but avoid thick tropical jungles and large deserts.  A belt of monsoons currently brings heavy rain to west central Africa, but this monsoon belt shifts every ~21,000 years, changing the zones of tropical forests and deserts.  Populations of lions become isolated from each other when their favored savannah habitat fragments and is separated by forest and desert.  Other species of savannah habitat show similar intraspecific genetic isolation including giraffe, water buffalo, bushbuck, waterbuck, hartebeest, warthog, cheetah, and spotted hyena.

The common ancestor of all present day clades of African lion diverged ~245,000 years ago.  The genetic evidence suggests all clades of lions were relegated to small refugia during the Last Glacial Maximum when much of Africa hosted landscapes unsuitable for the big cats.  Humans have recently translocated lions from different regions into other regions in an attempt to rebuild populations.  This interference results in the crossbreeding of different clades with each other.  Zoo lions are also crossbred clades for the most part.

References:

Barnett, Ross; et. al.

“Mitogenetics of the Extinct Cave Lion, Panthera spelaea, Resolve its Position Within the Panthera Cats”

Open Quaternary June 2016

Bertoli, L.S.; et. al.

“Philogeographic Pattern in Africa and High Resolution Delineation of Genetic Codes in the Lion (Panthera leo)

Scientific Reports May 2015