Bears of the Pleistocene

[brotherbear]

http://www.sciencedirect.com/science/art...8213007921

Behavioural ecology of Late Pleistocene bears (Ursus spelaeus, Ursus ingressus): Insight from stable isotopes (C, N, O) and tooth microwear.

Abstract
Several types of bears lived in Europe during the Late Pleistocene. Some of them, such as cave bears (Ursus s. spelaeus and Ursus ingressus), did not survive after about 25,000 years ago, while others are still extant, such as brown bear (Ursus arctos). Our article aims at a better understanding of the palaeoecology of these large “carnivores” and focuses on two regions, the Ach valley in the Swabian Jura (SW-Germany) with Geißenklösterle and Hohle Fels, and the Totes Gebirge (Austria) with Ramesch and Gamssulzen caves. Both regions revealed two genetically distinct cave bear lineages, and previous studies suggest behavioural differences for the respective bears in these two regions.

In the Ach valley, irrespective of the cave site, U. s. spelaeus was replaced by U. ingressus around 28 ka uncal BP with limited chronological overlap without recognizable dietary changes as documented by the isotopic composition (13C, 15N) of the bones. Furthermore, the present study shows that the dental microwear pattern was similar for all bears in both caves, however with a larger variability in Geißenklösterle than in Hohle Fels.

In contrast, the two Austrian caves, Gamssulzen (U. ingressus) and Ramesch (Ursus s. eremus), show considerable differences in both palaeodietary indicators, i.e., stable isotopes, and dental microwear, over at least 15,000 years. The oxygen and carbon analysis of the tooth enamel combined with the dental microwear of the same molars provide an extremely diversified picture of the feeding behaviour of these fossil bears. The already known differences between these two study areas are confirmed and refined using the new approaches. Moreover, the differences between the two cave bear lineages in the Totes Gebirge became even larger. Some niche partitioning between both types of cave bears was supported by the present study but it does not seem to be triggered by climate. This multi-disciplinary approach gives new insights into the palaeobiology of extinct bears. Reply

[GrizzlyClaws]

(10-02-2018, 04:43 AM)brotherbear Wrote: Post by brobear on 5 minutes ago
http://www.nationalgeographic.com/scienc...xtinction/  


Extinct Cave Bear DNA Found in Living Bears
The discovery is the first of its kind outside the human lineage.


After roaming Europe and Asia for more than a hundred thousand years, cave bears died out some 24,000 years ago, after a millennia-long death spiral possibly spurred by hunting, natural climate change, and competition with humans for habitat.

No cave bear has awoken from this final hibernation, but the animals' DNA lives on: A new study confirms that about 0.9 to 2.4 percent of living brown bears' DNA traces back to the extinct species.

The finding, published in Nature Ecology and Evolution on Monday, marks just the second time that researchers have found an extinct ice-age creature's genes within in a living relative. Humans are the first known example: Between 1.5 and four percent of the non-African human genome comes from Neanderthals, the product of interbreeding between our species and our ancient kin.


“By any standard definition, [cave bears] are extinct, but it doesn’t mean that their gene pool is erased, because they continue to live on in the genomes of these living animals,” says Axel Barlow, a postdoctoral researcher at the University of Potsdam and one of the study's lead authors.  


The study also reinforces that some species regularly interbreed. The DNA of yak and Tibetan cattle, for instance, show signs of interbreeding, as do pig species whose common ancestors lived millions of years ago. In a handful of cases, brown bears and polar bears have bred. And just last week, researchers unveiled the daughter of a Neanderthal woman and a Denisovan man—an example of what may have been widespread hybridization among ancient hominins.  


“The old-fashioned idea of a species [is that] it's reproductively isolated from other species,” says Rasmus Nielsen, a geneticist at the University of California, Berkeley, who wasn't involved with the study. “This paper is a part of a series of papers that have been saying that worldview really is wrong.”

Bearly Breeding?
To determine why cave bears died out, Barlow and his research team sought to study how the animals' populations grew and shrank, which they could infer from cave bear DNA extracted from the ear bones of four animals that lived more than 35,000 years ago.

First, the researchers compared the overall genomes of cave bears with polar bears and brown bears. Sure enough, the two living species were more related to each other than to cave bears. But the picture got more complex once researchers started counting up the bears' variants of individual genes.  

Since animal genomes are so large, there's ample room for random variation in certain genes. By chance alone, the same genes in distantly related animals can look similar, and the same genes of closely related animals can look different. In the absence of interbreeding, these quirks pile up in about equal amounts, much like flipping a coin—which isn't what researchers saw among the bears.


“If we get an overabundance of genome positions where cave bears and brown bears are showing more similarity to each other than to polar bears, then something else must have happened,” says Barlow. “And that something is hybridization between the two species.”


Not only did researchers see signs of interbreeding, but they also confirmed that hybrid bears could breed with either species. When Barlow and his colleague James Cahill combed through the species' genomes chunk by chunk, they found that brown bears and cave bears each had snippets of the other's DNA.  



“In my view, the concept of brown bears and cave bears interbreeding is not surprising, and it actually makes sense. Overall, they are very similar in appearance, and did overlap in time and space,” East Tennessee State University paleontologist Blaine Schubert says in an email. “However, this possibility was only speculation until the current study.”

The cave bears' genetic afterlife resembles Neanderthals' still-present influence on the human genome. But researchers emphasize that there are some major differences, as well.  
 


For one, modern humans and Neanderthals are closer relatives than brown bears and cave bears. It's also much easier to study humans and their closest extinct relatives, given the massive amount of sequenced human DNA. Limited data makes it hard to test whether brown bears make use of cave bears' gene variants. In humans, DNA from our archaic cousins affects our immunity, hair structure, and our ability to live in high altitudes, among other traits.

But even with limited data, Barlow marvels at what cave bears can still teach scientists, tens of thousands of years after their demise: “I think it’s really nice, because it forces us to think on a philosophical level what we mean by species extinction.”

Maybe the mutation of the Polar bear was triggered by the admixture from the Cave bear? Reply

[brotherbear]

http://www.researchgate.net/publication/...ic_Siberia


For a long time, “spelaeoid” (cave-bear-like) bears, Ursus (Spelearctos) spp., were believed to be almost purely European animals. Their geographic range has recently been extended to the east, in southern Siberia, Transbaikalia, Kirghizia, Mongolia and Korea. Two unexpected new findings, presented here in detail, significantly change existing views on the distribution of cave bears; both were found in North-Eastern Siberia, far beyond the Arctic Circle, more than 1500 km to the north-east of the previously accepted range. One of the fossils is a mandible, found near the town of Cherskiy at 68.73°N, 161.38°E. The analysis of local geology and accompanying mammal fossils suggests that it comes from the Olyorian Fauna (Early to early Middle Pleistocene). Morphologically, the Cherskiy mandible is closest to Ursus savini, a small middle Pleistocene cave bear from the British Cromer Forest-bed Formation, but differs in having a slightly more advanced dentition, and thus it is described as a new subspecies Ursus savini nordostensis. Another newly recognized fossil of the “spelaeoid” bear is an astragalus found at the Oskhordokh site at 67.54°N, 135.67°E, on a large gravel bar on the right bank of the Adycha River. This specimen is attributed to Ursus cf. deningeri. The paper also presents an interesting example of the interaction between classical and “molecular” palaeontology. The new finds significantly change existing ideas on the ecology and evolution of cave bears, some of the most remarkable members of the extinct Pleistocene megafauna

The first record of “spelaeoid” bears in Arctic Siberia | Request PDF. Available from: http://www.researchgate.net/publication/...ic_Siberia [accessed Oct 03 2018]. Reply

[brotherbear]

https://www.sciencedirect.com/science/ar...9517300384 
 
On the association of giant short-faced bear (Arctodus simus) and brown bear (Ursus arctos) in late Pleistocene North America. 
  Reply

[brotherbear]

When I look at pictures of giant panda bears or Andean bears on nature documentaries in the wild, I never see them in water. This leads me to believe that the short-faced bear group were not fishers. Aquatic life were probably not on their menu.
Another way of separating the two bear groups is "cat-skulled bears" ( short-faced bears ) and "dog-skulled bears" ( of the genus Ursus ). Both the panda bear and the Andean bear have extra-strong jaws... as did every cat-skulled bear I have researched.

Some information I read concerning the Andean bear's diet makes mention of the bear eating honey, some sites do not. I have read nothing of panda bear's eating honey. Could it be that those sites which mentions that Andean bears eat honey are merely making a generic statement based on the fact that they are bears? I have found no video's of either of these two cat-skulled bears eating honey. Reply

[epaiva]

Tremarctos floridanus
by Daniel Reed

*This image is copyright of its original author

Reply

[epaiva]

Where did the Bears really come from?
Sourse http://www.bearsinmind.org

*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

*This image is copyright of its original author

Reply

[brotherbear]

Home to the Pleistocene grizzly. Pleistocene American Fauna WIPby Dantheman9758
 

*This image is copyright of its original author

Reply

[Smilodon-Rex]

*This image is copyright of its original author

Missouri's monster————Short faced bear

*This image is copyright of its original author

Grizzly bear facing the Short faced bear

*This image is copyright of its original author

Smilodons and Short faced bear Reply

[Smilodon-Rex]

*This image is copyright of its original author

*This image is copyright of its original author

Panthera atrox skull(white）and Kodiak brown bear skull(grey) in comparison Reply

[epaiva]

Britain's Ice Age Mega Bears
Group World of Prehistoric Creatures

*This image is copyright of its original author

Reply

[brotherbear]

prehistoric-fauna.com/Ursus-priscus

Ursus priscus (Ursus priscus (GOLDFUSS, 1818))

Ursus arctos priscus

Pleistocene brown bear

Order: Carnivora

Family: Ursidae

Dimensions: length - 2,9 m, height - 140-160 сm, weight - 300-1000 kg

Temporal range:the Late Pleistocene - Holocene of Europe

From the beginning of the first scientific explorations of caves, the Zoolithenhöhle in Franconia, Germany, was famous for its rich fossil content. In addition to the numerous remains of cave bears and other animals, a skull of a clearly distinct kind of bear was found, originally called Ursus priscus GOLDFUSS, 1818. Three years later, the term Ursus fossilis was introduced along with a published description of the skull, which led to confusion about the adequate designation of the new species. U. priscus was regarded as a contemporary of the cave bear, i.e. Late Pleistocene in age, but the geological age of the find is still unclear even today, and from the overall state of preservation it could be even of Holocene age. The specimen probably represents a female individual. A revised study of the skull demonstrates that it is identical to modern U. arctos.On the basis of this evidence, U. priscus, U. fossilis and its synonyms are invalid terms. The nature of Late Pleistocene brown bears is still not well known.

1000 kilograms is equal to
2,204.62 pounds (avoirdupois) Reply

[epaiva]

(10-22-2018, 01:15 AM)brotherbear Wrote: prehistoric-fauna.com/Ursus-priscus

Ursus priscus (Ursus priscus (GOLDFUSS, 1818))

Ursus arctos priscus

Pleistocene brown bear

Order: Carnivora

Family: Ursidae

Dimensions: length - 2,9 m, height - 140-160 сm, weight - 300-1000 kg

Temporal range:the Late Pleistocene - Holocene of Europe

From the beginning of the first scientific explorations of caves, the Zoolithenhöhle in Franconia, Germany, was famous for its rich fossil content. In addition to the numerous remains of cave bears and other animals, a skull of a clearly distinct kind of bear was found, originally called Ursus priscus GOLDFUSS, 1818. Three years later, the term Ursus fossilis was introduced along with a published description of the skull, which led to confusion about the adequate designation of the new species. U. priscus was regarded as a contemporary of the cave bear, i.e. Late Pleistocene in age, but the geological age of the find is still unclear even today, and from the overall state of preservation it could be even of Holocene age. The specimen probably represents a female individual. A revised study of the skull demonstrates that it is identical to modern U. arctos.On the basis of this evidence, U. priscus, U. fossilis and its synonyms are invalid terms. The nature of Late Pleistocene brown bears is still not well known.
 
1000 kilograms is equal to
2,204.62 pounds (avoirdupois)

It was a huge Brown Bear larger than Kodiak Brown Bears Reply

[brotherbear]

Epaiva says: It was a huge Brown Bear larger than Kodiak Brown Bears. 
 
This brings to mind the now extinct California grizzly. I read the book, "California Grizzly" by Storer. It appears that this grizzly might have been a Kodiak-sized brown bear. Would you agree?  Pictured ( in art ) California grizzly meets short-faced bear. 
 

*This image is copyright of its original author

Reply

[Smilodon-Rex]

*This image is copyright of its original author

When Smilodon fatalis and Arctodus both standing up

*This image is copyright of its original author

Reply