Ursavus

[brobear]

phys.org/news/2014-08-nearest-ancestor-gansu-china.html Nearest ancestor of living bears discovered from Gansu, ChinaAugust 5, 2014In the last ten years or so, a number of skulls of Indarctos, Agriotherium and Ursavus have been collected from the Late Miocene deposits in the Linxia Basin. Since so far no complete Ursavus skull has ever been found and reported, and a number of questions pertaining to the origin, phylogeny and classification of the Ursinae are quite dependent on a better understanding of ancestral ursid members, especially the genus Ursavus, a well preserved skull of Ursavus was chosen as the subject of the first of a series of papers dealing with these ursid skulls by Professor Qiu Zhanxiang and his colleagues from Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences. The latest issue of Vertebrata PalAsiatica (Volume 52, Issue 3) published their research in the cover article.The Ursavus skull was collected in Huaigou village of Guanghe County, Linxia Hui Autonomous Prefecture, Gansu Province in July, 2006. Ancestral ursine fossils, especially those of Ursavus, are frequently found in Holarctic Miocene deposits, but mainly represented by teeth and fragmentary mandibles. The best specimen so far known is an anterior half of skull from the Island of Euboea (Greece), described in detail by Thenius in 1947. Another better preserved specimen is a skeleton from Shanwang, China, first described as Ursavus orientalis, but later reassigned to the genus Ballusia, of which only brief description of some teeth was reported by Qiu et al. in 1985. The present skull from Huaigou is thus the first and only complete skull with its associated mandible ever known of these early ursine bears.From the same locality where this skull was found, rich fossils of typical North China Hipparion fauna were found. A preliminary list of the mammalian fossils includes: Promephitis, Metailurus, Machairodus, Ictitherium, Hyaenictitherium, Hipparion, Chilotherium, Sinotherium, Palaeotragus, and Prosinotragus. Of them Promephitis and Sinotherium have already been studied (Wang and Qiu, 2004; Deng et al., 2013). An age determination based on the evolutionary level of the Promephitis species was given as around 9−7 Ma, while on the other hand, 7 Ma was given by Deng et al., based on the presence of Sinotherium lagrelii. It is better to be considered as around 8 Ma for this locality.The genus Ursavus had occupied a central position in study of the early ancestral forms of the living bears prior to the 1940's. Almost every student studying ursid carnivores had considered Ursavus the unique ancestor of living bears since the end of the 19th century. The genus Ursavus was established by Schlosser in 1899, based mainly on the material of U. brevirhinus (two incomplete hemimandibles, one maxillary with upper dentition, and some isolated teeth) from three localities (Steieregg and Voitsberg, Austria; and Kieferstadtel in Oppeln, now Poland).From the context of Schlosser's description the following can be viewed as more diagnostic for his new genus, in comparison with the living bears: size is small, about wolf-sized. Canines are more laterally compressed, with clear anterior and posterior keels. Premolars are always four in number, separated by short diastemata. Except P4, all premolars are simple, without secondary cusplets. The second and third premolars are double-rooted. P4 metastyle is blade-shaped, its protocone considerably far posteriorly shifted, with strong inner cingulum. The crown surfaces of molars are strongly wrinkled. Upper molars are rectangular, slightly longer than wide, each with two outer and two inner cusps, massive inner basal bulge and well developed external cingulum. M2 has short talon. The m1 trigonid is much higher than its talonid, which is large, with strong, but low hypoconid and small entoconid. The m2 protoconid is low, but metaconid considerably strong, without paraconid. The m3 is knob-formed.Later, with increasing finds of new materials from Early and Middle Miocene deposits, majority of which were, unfortunately, isolated teeth, Ursavus had gradually become a large heterogeneous genus. Up to now, 11 forms of this genus have been established. Opinions differed widely among paleontologists as to the reliability of referral of some of these species to the genus Ursavus. At least two species, U. depereti and U. elmensis, were formally excluded from the genus Ursavus. While establishing a new genus, Agriarctos, based on some isolated lower cheek teeth from the latest Miocene deposits in Hungary, Kretzoi (1942) transferred the type specimen of Ursavus depereti to his new genus Agriarctos, and tended to associate it with his smaller species, Agriarctos vighi. Based mainly on the diagnostic characters of the m1, i.e., the tooth being short and wide, with strong, anteriorly shifted metaconid, thus forming a rather closed trigonid, Agriarctos was considered by Kretzoi an intermediate form between Ursavus and the Agriotherium-Indarctos lineage. Qiu and Qi in 1989 established a new genus and species, Ailurarctos lufengensis, belonging to the giant panda lineage, based on a few isolated teeth from the famous Lufengpithecus site in Yunnan, China, which were originally referred to Ursavus.Ginsburg and Morales (1998) also established a new genus, Ballusia, based on Ursavus elmensis. Diagnostic features of this new genus can be summarized as: size generally smaller than Ursavus; the lingual crest (formed by protocone and metaconule) of upper molars widely separated from the buccal cusps (paracone and metacone); lingual cingulum wider and more curved; M2 clearly elliptical, with short but wider talon; the m1 resembling those of Hemicyon and Plithocyon in having higher trigonid. They suggested that U. orientalis might be close to the root of this lineage so that Qiu and Qiu (2013) temporarily transferred it to the genus Ballusia.Just recently, Abella et al. (2012) created a new genus, Kretzoiarctos, based on a combination of a partially preserved right hemimandible with a left P4 and an M1 from Spain, first identified as a new species of Agriarctos. Based on cladistic analysis, Abella and colleagues concluded that Kretzoiarctos beatrix was the oldest recorded member of the giant panda lineage. Their Ailuropodinae include two subclades: the Indarctos one and the ailuropod one, with Ailuropoda being the first split from the remaining members of the latter subclade. Qiu and colleagues' cladogram shows that Kretzoiarctos is a sister taxon to the other two genera (Agriarctos and Ailuractos). Since Ailuractos is certainly the earliest know ancestral taxon leading to Ailuropoda as clearly evidenced by the tooth morphology, Kretzoiarctos may not be directly ancestral to Ailuropoda. In fact, K. beatrix does not possess the key characters leading to Ailuropoda: the enlargement of the premolars, especially the anterior and posterior accessory cusps and the short and V-shaped m1 trigonid. On the other hand, these characters, together with the presence of small parastyle and doubled protocone of P4, can be found in Indarctos species. Thus, it is highly possible that Kretzoiarctos is the ancestral taxon of Indarctos clade, rather than that of Ailuropoda.

Ginsburg and Morales (1998) came to the conclusion that the earliest member of the Ursinae is Ballusia, which gave rise to the Ursavus-Ursus lineage, while Agriarctos gave rise successively to Agriotherium and Indarctos, and finally Ailurarctos and Ailuropoda formed the pair of sister taxa. As thus defined, the primitive members of the Ursidae include: Ballusia (3 species), Ursavus (8 species), Agriarctos (3 species), Ailurarctos lufengensis and Kretzoiarctos beatrix, altogether 5 genera and 16 species.

So far no complete skull in association with its mandible has ever been described for any of the genera Ballusia, Ursavus, Kretzoiarctos, Agriarctos and Ailurarctos. The best material so far known is an anterior half of skull published in 1947 and two fragmentary hemimandibles described in 1887. This blank is now filled by the Huaigou specimen. Being one of the latest occurred (~8 Ma) and highly advanced member of the early ancestral ursids, the Huaigou skull may be quite different from the majority of the species in Early-Middle Miocene and early Late Miocene in possessing more advanced characters leading to the living bears.It seems safe to say that the Huaigou specimen cannot be ascribed to any of known ancestral forms of the living bears, so this specimen warrants a separate species status, here named as Ursavus tedfordi. The species name is to cherish the memory of Richard Hall Tedford, the great North American Neogene biostratigrapher and paleomammalogist, who recently passed away on July 16, 2011. U. tedfordi is a large-sized Ursavus species, roughly intermediate between Cephalogale minor and Selenarctos thibetanus in size, proportion and morphology. Its diagnostic characters include: the muzzle is short and broad compared with the back part of the skull; the sagittal crest is enormously high posteriorly, overhanging far beyond the nuchal surface; the cranial part is narrow compared with the facial part; the tympanic bulla is triangular in form, with a short tubular external auditory meatus; the mandible is robust; premolars are strongly reduced in size and button-shaped; enamel wrinkles are hardly developed on cheek teeth.

Taken as a whole, there is no doubt that Ursavus tedfordi is the latest and the most advanced among known ancestral forms of the living ursine bears. However, in view of the precocious appearance of some features not seen in the living ursine bears, U. tedfordi might well be an aberrant form, being one of the latest sister taxa of the clade consisting of the living ursine bears.

Read more at: phys.org/news/2014-08-nearest-ancestor-gansu-china.html#jCp

[brobear]

It seems that the naming of this species is based on a few teeth found at Hambach mine horizon 6C (Miocene of Germany). Named by Stehlin 1917. Picture by Margaret Lambert.

Lived from ~16.9—13.7 Ma.
Source: en.wikipedia.org/wiki/Ursavus

Age range: MN 5 or 15.970 to 13.650 Ma
Source: paleodb.org

"The first true bear is obviously impossible to identify, due to the incomplete fossil record and a somewhat ambiguous definition as to what a bear is. Renowned paleontologist Bjorn Kurtén pointed to Ursavus elmensis (although known only from its teeth and jaws) as a likely candidate, thus attracting the name “dawn bear”."
Source: www.lynxeds.com/hmw/family-text/hmw-1-family-text-hyaenidae-hyenas

"Ursavus elmensis, also known as the dawn bear, was the last species to evolve in the Ursavus genus. It lived during the early Miocene epoch (over 20 million years ago) in what was at that time a subtropical Europe. About 10 million years ago, Ursavus elmensis is believed to have given rise to Protursus simpsoni from which the Ursus line evolved. Although Ursavus elmensis is the first recognizable species of "true bear" known to have existed, it is believed to have been outlived by Ursavus depereti which is believed to have produced Indarctos and Agriotherium.

Ursavus elmensis was only the size of a fox terrier and retained many dog-like characteristics. It is believed to have done most of its hunting in trees like its ancestors, feeding on mainly vegetation and insects. By the Pleistocene epoch (1.8 million to 10,000 years ago), its decendents had evolved into some of the largest carnivorous mammals ever known. All modern bears are believed to have branched from Ursavus. The Ursavus line became extinct 8 to 7 million years ago when climate of the northern hemisphere became much drier, turning subtropical forests more into deserts."
Source: bearsoftheworld.net/ursavus_elmensis.asp

[King Kodiak]

Great info brobear, nice.

Ursavus Tedfordi recreation (a different species)




prehistoric-fauna.com/Ursavus

[OldGreenGrolar]

This type of bear has a long tail.

[King Kodiak]

Nov 13, 2019 7:04:07 GMT -5 OldGreenGrolar said:

This type of bear has a long tail.

Yeah, good observation.

[brobear]

Ursavus elmensis - the first bear. The one who started it all. The granddaddy of bears.    
 

Reply #1 - nice find King.

[brobear]

Ursavus is an extinct genus of bear that existed in North America, Europe, and Asia during the Miocene, about 23–5.3 million years ago (Mya), existing for roughly 17.7 million years. The genus apparently dispersed from Asia into North America about 20 Mya, becoming the earliest member of the subfamily Ursinae in the New World.[4] Qiu points out that if a questionable 29 million-year-old specimen of Ursavus reported in North America is validated, Ursavus may have evolved in North America and dispersed westward into Asia. The higher number of fossils in Europe grading toward eastern Asia make the westward dispersal unlikely.

U. elmensis, also known as the "dawn bear" is generally taken to be the earliest undisputed bear species

In life, the various species would have been between cat-sized for the smaller species and wolf-sized for the larger members of the genus and were mainly omnivores or hypocarnivores.

Most other species are known from teeth and skull fragments. A complete skull has been found in the Gansu region of China of a new species from the late Miocene, dubbed U. tedfordi. It was about the size of a wolf and – except for the giant panda and the spectacled bear – is believed to be the nearest to the common ancestor of modern bears.

Currently, the only member known from a complete skeleton is U. orientalis, found in the Shanwang diatomite of Early Miocene China. However, Qiu et.al. (2014) have suggested reassignment of U. orientalis to the genus Ballusia, in which case it would no longer be considered part of Ursavus.

†Ursavus brevirhinus (Hofmann, 1887)
†Ursavus primaevus (Gaillard, 1899)
†Ursavus intermedius (Koenigswald, 1925)
†Ursavus pawniensis (Frick, 1926)
†Ursavus ehrenbergi (Brunner, 1942)
†Ursavus sylvestris (Qiu & Qi, 1990)
†Ursavus isorei (Ginsburg & Morales, 1998)
†Ursavus tedfordi (Zhanxiang et al., 2014)

[brobear]

Ursavus, genus of ursid carnivoran mammal from Miocene Asia, Europe and North America.

It was about 1.3 m. long and 55 cm high.

It's thought to have evolved from the bear-dogs.

[brobear]

Ursavus - prehistoric-fauna.com/Ursavus 
 
Ursavus (Ursavus Schlosser 1899)

Order: Carnivora

Suborder: Caniformia

Superfamily: Arctoidea

Family: Ursidae

Size: 1.3 m in length, 55 cm in height, 60 kg of weight

Time period: the Miocene of North America, Europe, and Asia (~23—5.3 Ma)

Type species: Ursavus brevirhinus

Ursavus is an extinct genus of ursid carnivoran mammals that existed in North America, Europe, and Asia during the Miocene, living from ~23—5.3 Ma, existing for approximately 17.7 million years. It evolved from the bear-dog. The genus apparently dispersed from Asia into North America about 20 Ma, becoming the earliest member of the subfamily Ursinae in the New World. Qiu points out that if a questionable 29 million-year-old specimen of Ursavus reported in North America is validated, Ursavus may have evolved in North America and dispersed westward into Asia. The higher number of fossils in Europe grading toward eastern Asia make the westward dispersal unlikely.

Ursavus was named by Schlosser (1899). It was assigned to Ursidae by Schlosser (1899) and R. L. Carroll (1988); and to Ursavini by R.M. Hunt (1998) and Jin et al. (2007). In life, the various species would have been between cat-sized for the smaller species, and wolf-sized for the larger members of the genus and were mainly ground-dwelling omnivores or hypocarnivores.
U. elmensis, also known as the "dawn bear" is generally taken to be the earliest undisputed bear species.
Currently, only U. orientalis, from the Shanwang diatomite of Early Miocene China, is known from a complete skeleton.However, U. orientalis may have been reassigned to the genus Ballusia and is thus no longer considered part of Ursavus.

Most other species are known from teeth and skull fragments. A complete skull has been found in the Gansu region of China of a new species dubbed U. tedfordi. From the late Miocene, it was about the size of a wolf and is believed to be nearest ancestor of most modern bear species apart from the Giant Panda and Spectacled Bear.

[brobear]

phys.org/news/2014-08-nearest-ancestor-gansu-china.html

Nearest ancestor of living bears discovered from Gansu, China.

In the last ten years or so, a number of skulls of Indarctos, Agriotherium and Ursavus have been collected from the Late Miocene deposits in the Linxia Basin. Since so far no complete Ursavus skull has ever been found and reported, and a number of questions pertaining to the origin, phylogeny and classification of the Ursinae are quite dependent on a better understanding of ancestral ursid members, especially the genus Ursavus, a well preserved skull of Ursavus was chosen as the subject of the first of a series of papers dealing with these ursid skulls by Professor Qiu Zhanxiang and his colleagues from Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences. The latest issue of Vertebrata PalAsiatica (Volume 52, Issue 3) published their research in the cover article.

The Ursavus skull was collected in Huaigou village of Guanghe County, Linxia Hui Autonomous Prefecture, Gansu Province in July, 2006. Ancestral ursine fossils, especially those of Ursavus, are frequently found in Holarctic Miocene deposits, but mainly represented by teeth and fragmentary mandibles. The best specimen so far known is an anterior half of skull from the Island of Euboea (Greece), described in detail by Thenius in 1947. Another better preserved specimen is a skeleton from Shanwang, China, first described as Ursavus orientalis, but later reassigned to the genus Ballusia, of which only brief description of some teeth was reported by Qiu et al. in 1985. The present skull from Huaigou is thus the first and only complete skull with its associated mandible ever known of these early ursine bears.

From the same locality where this skull was found, rich fossils of typical North China Hipparion fauna were found. A preliminary list of the mammalian fossils includes: Promephitis, Metailurus, Machairodus, Ictitherium, Hyaenictitherium, Hipparion, Chilotherium, Sinotherium, Palaeotragus, and Prosinotragus. Of them Promephitis and Sinotherium have already been studied (Wang and Qiu, 2004; Deng et al., 2013). An age determination based on the evolutionary level of the Promephitis species was given as around 9−7 Ma, while on the other hand, 7 Ma was given by Deng et al., based on the presence of Sinotherium lagrelii. It is better to be considered as around 8 Ma for this locality.

The genus Ursavus had occupied a central position in study of the early ancestral forms of the living bears prior to the 1940's. Almost every student studying ursid carnivores had considered Ursavus the unique ancestor of living bears since the end of the 19th century. The genus Ursavus was established by Schlosser in 1899, based mainly on the material of U. brevirhinus (two incomplete hemimandibles, one maxillary with upper dentition, and some isolated teeth) from three localities (Steieregg and Voitsberg, Austria; and Kieferstadtel in Oppeln, now Poland).

From the context of Schlosser's description the following can be viewed as more diagnostic for his new genus, in comparison with the living bears: size is small, about wolf-sized. Canines are more laterally compressed, with clear anterior and posterior keels. Premolars are always four in number, separated by short diastemata. Except P4, all premolars are simple, without secondary cusplets. The second and third premolars are double-rooted. P4 metastyle is blade-shaped, its protocone considerably far posteriorly shifted, with strong inner cingulum. The crown surfaces of molars are strongly wrinkled. Upper molars are rectangular, slightly longer than wide, each with two outer and two inner cusps, massive inner basal bulge and well developed external cingulum. M2 has short talon. The m1 trigonid is much higher than its talonid, which is large, with strong, but low hypoconid and small entoconid. The m2 protoconid is low, but metaconid considerably strong, without paraconid. The m3 is knob-formed.
                                                                                              

[brobear]

Nearest ancestor of living bears discovered from Gansu, China... continued:

Later, with increasing finds of new materials from Early and Middle Miocene deposits, majority of which were, unfortunately, isolated teeth, Ursavus had gradually become a large heterogeneous genus. Up to now, 11 forms of this genus have been established. Opinions differed widely among paleontologists as to the reliability of referral of some of these species to the genus Ursavus. At least two species, U. depereti and U. elmensis, were formally excluded from the genus Ursavus. While establishing a new genus, Agriarctos, based on some isolated lower cheek teeth from the latest Miocene deposits in Hungary, Kretzoi (1942) transferred the type specimen of Ursavus depereti to his new genus Agriarctos, and tended to associate it with his smaller species, Agriarctos vighi. Based mainly on the diagnostic characters of the m1, i.e., the tooth being short and wide, with strong, anteriorly shifted metaconid, thus forming a rather closed trigonid, Agriarctos was considered by Kretzoi an intermediate form between Ursavus and the Agriotherium-Indarctos lineage. Qiu and Qi in 1989 established a new genus and species, Ailurarctos lufengensis, belonging to the giant panda lineage, based on a few isolated teeth from the famous Lufengpithecus site in Yunnan, China, which were originally referred to Ursavus.

Ginsburg and Morales (1998) also established a new genus, Ballusia, based on Ursavus elmensis. Diagnostic features of this new genus can be summarized as: size generally smaller than Ursavus; the lingual crest (formed by protocone and metaconule) of upper molars widely separated from the buccal cusps (paracone and metacone); lingual cingulum wider and more curved; M2 clearly elliptical, with short but wider talon; the m1 resembling those of Hemicyon and Plithocyon in having higher trigonid. They suggested that U. orientalis might be close to the root of this lineage so that Qiu and Qiu (2013) temporarily transferred it to the genus Ballusia.
                                    

[brobear]

Nearest ancestor of living bears discovered from Gansu, China... continued:

Just recently, Abella et al. (2012) created a new genus, Kretzoiarctos, based on a combination of a partially preserved right hemimandible with a left P4 and an M1 from Spain, first identified as a new species of Agriarctos. Based on cladistic analysis, Abella and colleagues concluded that Kretzoiarctos beatrix was the oldest recorded member of the giant panda lineage. Their Ailuropodinae include two subclades: the Indarctos one and the ailuropod one, with Ailuropoda being the first split from the remaining members of the latter subclade. Qiu and colleagues' cladogram shows that Kretzoiarctos is a sister taxon to the other two genera (Agriarctos and Ailuractos). Since Ailuractos is certainly the earliest know ancestral taxon leading to Ailuropoda as clearly evidenced by the tooth morphology, Kretzoiarctos may not be directly ancestral to Ailuropoda. In fact, K. beatrix does not possess the key characters leading to Ailuropoda: the enlargement of the premolars, especially the anterior and posterior accessory cusps and the short and V-shaped m1 trigonid. On the other hand, these characters, together with the presence of small parastyle and doubled protocone of P4, can be found in Indarctos species. Thus, it is highly possible that Kretzoiarctos is the ancestral taxon of Indarctos clade, rather than that of Ailuropoda.

Ginsburg and Morales (1998) came to the conclusion that the earliest member of the Ursinae is Ballusia, which gave rise to the Ursavus-Ursus lineage, while Agriarctos gave rise successively to Agriotherium and Indarctos, and finally Ailurarctos and Ailuropoda formed the pair of sister taxa. As thus defined, the primitive members of the Ursidae include: Ballusia (3 species), Ursavus (8 species), Agriarctos (3 species), Ailurarctos lufengensis and Kretzoiarctos beatrix, altogether 5 genera and 16 species.

So far no complete skull in association with its mandible has ever been described for any of the genera Ballusia, Ursavus, Kretzoiarctos, Agriarctos and Ailurarctos. The best material so far known is an anterior half of skull published in 1947 and two fragmentary hemimandibles described in 1887. This blank is now filled by the Huaigou specimen. Being one of the latest occurred (~8 Ma) and highly advanced member of the early ancestral ursids, the Huaigou skull may be quite different from the majority of the species in Early-Middle Miocene and early Late Miocene in possessing more advanced characters leading to the living bears.

It seems safe to say that the Huaigou specimen cannot be ascribed to any of known ancestral forms of the living bears, so this specimen warrants a separate species status, here named as Ursavus tedfordi. The species name is to cherish the memory of Richard Hall Tedford, the great North American Neogene biostratigrapher and paleomammalogist, who recently passed away on July 16, 2011. U. tedfordi is a large-sized Ursavus species, roughly intermediate between Cephalogale minor and Selenarctos thibetanus in size, proportion and morphology. Its diagnostic characters include: the muzzle is short and broad compared with the back part of the skull; the sagittal crest is enormously high posteriorly, overhanging far beyond the nuchal surface; the cranial part is narrow compared with the facial part; the tympanic bulla is triangular in form, with a short tubular external auditory meatus; the mandible is robust; premolars are strongly reduced in size and button-shaped; enamel wrinkles are hardly developed on cheek teeth.
                                                

[brobear]

Nearest ancestor of living bears discovered from Gansu, China... continued:

Taken as a whole, there is no doubt that Ursavus tedfordi is the latest and the most advanced among known ancestral forms of the living ursine bears. However, in view of the precocious appearance of some features not seen in the living ursine bears, U. tedfordi might well be an aberrant form, being one of the latest sister taxa of the clade consisting of the living ursine bears.
                                                                           

[brobear]

Reply #9 through #12: The lineage and connections of these early bears can be quite confusing; even to the experts.

[brobear]

What’s the Oldest Bear Fossil Ever Found?

a-z-animals.com/blog/whats-the-oldest-bear-fossil-ever-found/

Bears are mostly large, strong mammals that live in many places throughout the world. Have you ever wondered where they come from originally or what their oldest ancestors are? Today, we’re going to examine the oldest bear fossil ever found. We’ll track the evolution of bears from far in the past into the present and show you the oldest true bears that ever lived.

The first ancestors of modern bears appeared about at some point during the Eocene, between 55.8 and 33.9 million years ago. This epoch is when the earliest fossil evidence of modern mammals belonging to the clade Carnivoraformes appeared. These mammals were small and light, most of them weighing less than 50 pounds. The most interesting thing about them is that they were carnivores.

Two options have emerged as the earliest relatives of bears. They are Dormaalocyon latouri and Parictis. One of the earliest bear ancestors was Dormaalocyon latouri since it was also one of the earliest carnivores ever found. This creature appeared about 56 to 55 million years ago in Europe. This species was only discovered in 2014, and scientists estimate that it weighed about 2 pounds.

Dormaalocyon latouri
This bear is so ancient that it is probably related to a host of modern carnivores rather than just being a bear ancestor.

[brobear]

So, if we turn our focus away from the earliest carnivores and focus on something a little closer to bears. Parictis was an arctoid that looked something like a raccoon rather than the larger creatures one might expect of bears. This genus of arctoids lived in North America around 38 million years ago. While this creature and the clade that it belonged to, Amphicynodontidae, could have been a type of early bear, it may be more of a forebear of pinnipeds than the Ursus genus. That would make it an ancestor of modern seals.

As you can see, the ancestors of modern bears go back almost to the beginning of the Cenozoic. If we consider these creatures bears, which may be irresponsible, then the Dormaalocyon latouri would have the oldest bear fossils ever found. Instead, we’re going to look farther ahead in time.

[brobear]

The first true bears came from Ursavus, a genus that arose about 23 million years ago and lasted until about 5.3 million years ago. A particular species, Ursavus elmensis, also called the dawn bear, was the first member of this genus to appear. This species is often recognized as the first true bear, and it was roughly the size of a fox terrier.

This bear first appeared in Europe, but it and other members of the genus soon spread into Asia and eventually North America. Now that we have identified the first true bears, we can start to look at the age of the oldest bear fossil ever found.

A particular species, Ursavus elmensis, also called the dawn bear, was the first member of this genus to appear.

[brobear]

The oldest bear fossil ever found were up to 23.03 years old. Specifically, the fossils’ age range could have been anywhere between 23.03 and 5.33 million years old.

The fossils belonged to the species Ursavus elmensis, the first species of true bears. Pierre Mein, a French paleontologist, found the fossils in 1958. He discovered the fossils in the Bourgogne-Franche-Comté of France.

Other old Ursavus elmensis fossils have been discovered in other places in Europe as well. One collection found in Germany is roughly 15.97 million years old.

So, if we count Ursavus elmensis as the oldest bear, then these are the oldest bear fossils ever found. At least, those are the oldest ones recorded so far. Some controversy surrounding Ursavus species has arisen. Research concerning the origin of Ursavus has repeated references to a 29-million-year-old specimen.

Apparently, a member of Ursavus may have been in North America before the Ursavus elmensis and its descendants traveled there from Europe and Asia. However, no further information has been presented about this supposed specimen, so we’re simply going to put the exploration of that creature on hold for now.

Apparently, a member of Ursavus may have been in North America before the Ursavus elmensis and its descendants traveled there from Europe and Asia.

[brobear]

The oldest modern bear fossil is about 7 to 8 million years old, and it belongs to an ancestor of the giant panda bear! That’s right, the oldest fossils of an extant bear species are from the creature that directly preceded the giant panda.

The fossils of Ailurarctos, the creature from which the giant panda would descend, had many of the same mouth characteristics of the modern species. These traits allow the panda to eat bamboo.

However, it’s not sufficient to say that pandas are simply the oldest bear species alive today. It’s just that scientists have collected older evidence of their existence and persistent traits for this species than others. Furthermore, paleontologists have recovered fossil specimens that make it easier to trace the lineage of these bears than others, possibly due to their unique qualities.

The oldest bear fossils ever found taught scientists a great deal. They learned that bears arose from Europe or Asia and then radiated outward into the world. Moreover, scientists have found that some of the creatures that would later become bears were also some of the earliest carnivores to ever exist.

However, many questions still remain about the exact evolution and timeline of bears.

The species as we know them today are very different from anything that existed in the past. Bear relatives underwent a serious increase in size throughout their history. Remember, 23 million years ago, bear ancestors were the size of a small dog.

Meanwhile, some of the largest bear species to exist lived 12,000 years ago or less. They could have weighed as much as 2,600 or over 3,000 pounds!

Filling in the gaps between the earliest species and the extant species will help humans get a better understanding of how, when, and where bears developed. However, such an effort will be difficult at best and may be impossible.

The oldest bear fossils ever found taught scientists a great deal. They learned that bears arose from Europe or Asia and then radiated outward into the world.