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{{Short description|Extinct genus of carnivores}}
{{Short description|Extinct genus of bears}}
{{Automatic taxobox
{{Automatic taxobox
| fossil_range = {{Fossil range|13.6|2.5}}
| fossil_range = {{Fossil range|13.6|2.5}}
| image = OR39721-S.jpg
| image = OR39721-S.jpg
| image_caption = Views of skull
| image_caption = Views of skull
| parent_authority = Kretzoi, 1929
| taxon = Agriotherium
| taxon = Agriotherium
| authority = Wagner, 1837
| authority = Wagner, 1837
| type_species = †'''''Agriotherium sivalensis'''''
| type_species = {{extinct}}''Ursus sivalensis'' <br>(= †'''''Agriotherium sivalensis''''')
| type_species_authority = Falconer & Cautley, 1836
| type_species_authority = Falconer & Cautley, 1836
| subdivision_ranks = Species<ref>Ogino, Shintaro, Naoko Egi, and Masanaru Takai. "New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar." ''Journal of Asian Earth Sciences'' 42.3 (2011): 408-414.</ref>
| subdivision_ranks = Species
| subdivision_ref = <ref>Ogino, Shintaro, Naoko Egi, and Masanaru Takai. "New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar." ''Journal of Asian Earth Sciences'' 42.3 (2011): 408-414.</ref>
| subdivision =
| subdivision =
†''A. myanmarensis'' <small>(Ogino et al., 2011)</small><br>
†''A. myanmarensis'' <small>(Ogino et al., 2011)</small><br>
Line 17: Line 17:
†''A. sivalensis'' <small>(Falconer & Cautley, 1836)</small><br>
†''A. sivalensis'' <small>(Falconer & Cautley, 1836)</small><br>
†''A. africanum'' <small>(Hendey, 1972)</small><br>
†''A. africanum'' <small>(Hendey, 1972)</small><br>
†''A. coffeyi'' <small>(Dalquest, 1986)</small><br>
†''A. hendeyi'' <small>Jiangzuo and Flynn, 2019</small><br>
†''A. gregoryi'' <small>(Frick, 1926)</small><br>
†''A. schneideri'' <small>(Sellards, 1916)</small>
}}
}}


'''''Agriotherium''''' is an extinct genus of [[Ursidae|bears]] whose fossils are found in [[Miocene]] through [[Pleistocene]]-aged strata of [[North America]], [[Europe]], [[Africa]], and [[Asia]]. This long-lived genus persisted from at least ~11.6–2.5 [[Annum|Mya.]]<ref>{{Cite web|url=http://fossilworks.org/?a=taxonInfo&taxon_no=41303|title=Fossilworks: Agriotherium|website=fossilworks.org|access-date=2020-03-16}}</ref> Materials from the late-surviving ''A. africanum'' in Africa have suggested that ''A. africanum'' died out during the early [[Gelasian]].<ref>{{Cite web|url=http://fossilworks.org/bridge.pl?a=taxonInfo&taxon_no=199981|title=Fossilworks: Agriotherium africanum|website=fossilworks.org|access-date=2020-03-16}}</ref>
'''''Agriotherium''''' is an extinct genus of [[Ursidae|bears]] whose fossils are found in [[Miocene]] through [[Pleistocene]]-aged strata of [[North America]], [[Eurasia]], and [[Africa]]. This long-lived genus persisted from at least ~11.6–2.5 [[Annum|Mya.]]<ref>{{Cite web|url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=41303|title=Fossilworks: Agriotherium|website=fossilworks.org|access-date=17 December 2021}}</ref> Materials from the late-surviving ''A. africanum'' in Africa have suggested that ''A. africanum'' died out during the early [[Gelasian]].<ref>{{Cite web|url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=199981|title=Fossilworks: Agriotherium africanum|website=fossilworks.org|access-date=17 December 2021}}</ref>


==Description and diet==
==Description and diet==
[[File:Agriotherium maraghanus mandible.JPG|thumb|left|Mandible]]
[[File:Agriotherium maraghanus mandible.JPG|thumb|left|Mandible]]
''Agriotherium'' measured up to {{convert|2.7|m|ft|sigfig=1}} in body length and weighed around {{convert|900|kg|sigfig=3}}, making it larger than most living bears. Along with other large bears such as the [[cave bear]], short-faced bears ''[[Arctodus]]'' and ''[[Arctotherium]]'', and an extinct subspecies of the modern polar bear ''[[Ursus maritimus tyrannus]]'', ''Agriotherium'' was among the largest known terrestrial members of [[Carnivora]]. They had longer legs and shorter faces than other bears, and were more lightly built. Their wide, short jaws could generate enormous bite force. It is not certain how this force was used by the living animal; a study designed to determine how the genus fed discovered that among living bears, the lowest bite force belongs to the predatory polar bear, which feeds largely on blubber, and the highest bite force belongs to the giant panda, a herbivore which uses it to crush [[bamboo]]. Shortened jaws with high bite forces are found in other mammals like [[Theropithecus|Gelada baboons]] that eat grasses but evolved from non-grazing ancestors, and in bone-crushing scavengers, like [[spotted hyena]]s and [[Borophaginae|borphagine]] dogs.<ref>{{Cite journal|last1=Oldfield|first1=C. C.|last2=McHenry|first2=C. R.|last3=Clausen|first3=P. D.|last4=Chamoli|first4=U.|last5=Parr|first5=W. C. H.|last6=Stynder|first6=D. D.|last7=Wroe|first7=S.|date=2012|title=Finite element analysis of ursid cranial mechanics and the prediction of feeding behaviour in the extinct giant Agriotherium africanum|url=https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-7998.2011.00862.x|journal=Journal of Zoology|language=en|volume=286|issue=2|pages=171|doi=10.1111/j.1469-7998.2011.00862.x|issn=1469-7998|doi-access=free}}</ref><ref>{{Cite news|last=Switek|first=Brian|url=https://www.wired.com/2012/10/researchers-chew-over-a-prehistoric-bears-diet/|title=Researchers Chew Over a Prehistoric Bear's Diet|date=2012-10-29|work=Wired|access-date=2020-03-16|issn=1059-1028}}</ref>
''A. africanum'' measured around {{convert|2|m|ft|sigfig=1}} in body length and weighed up to {{convert|750|kg|sigfig=3}},<ref>{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|location=London|page= 217|isbn= 1-84028-152-9}}</ref><ref>Burness, G. P., Diamond, J., & Flannery, T. (2001). Dinosaurs, dragons, and dwarfs: The evolution of maximal body size. ''Proceedings of the National Academy of Sciences, '''98'''''(25), 14518–14523. https://doi.org/10.1073/pnas.251548698</ref> making it larger than most living bears; however, mass estimates vary, with further studies presenting a lower mass estimate of {{convert|317|–|540|kg|sigfig=3}}.<ref name="bite">{{Cite journal|last1=Oldfield|first1=C. C.|last2=McHenry|first2=C. R.|last3=Clausen|first3=P. D.|last4=Chamoli|first4=U.|last5=Parr|first5=W. C. H.|last6=Stynder|first6=D. D.|last7=Wroe|first7=S.|date=2012|title=Finite element analysis of ursid cranial mechanics and the prediction of feeding behaviour in the extinct giant Agriotherium africanum|journal=Journal of Zoology|language=en|volume=286|issue=2|pages=171|doi=10.1111/j.1469-7998.2011.00862.x|issn=1469-7998|doi-access=}}</ref><ref>Sorkin, B. (2006). Ecomorphology of the giant short-faced bears ''Agriotherium'' and ''Arctodus''. ''Historical Biology, '''18'''''(1), 1–20. https://doi.org/10.1080/08912960500476366</ref> Along with other large bears such as the [[cave bear]], short-faced bears ''[[Arctodus]]'' and ''[[Arctotherium]]'', and an extinct subspecies of the modern polar bear ''[[Ursus maritimus tyrannus]]'', ''Agriotherium'' was among the largest known terrestrial members of [[Carnivora]]. They had longer legs and shorter faces than other bears, and were more lightly built. Their wide, short jaws could generate enormous bite force. It is not certain how this force was used by the living animal; a study designed to determine how the genus fed discovered that among living bears, the lowest bite force belongs to the predatory polar bear, which feeds largely on blubber, and the highest bite force belongs to the giant panda, a herbivore which uses it to crush [[bamboo]]. Shortened jaws with high bite forces are found in other mammals like [[Theropithecus|Gelada baboons]] that eat grasses but evolved from non-grazing ancestors, and in bone-crushing scavengers, like [[spotted hyena]]s and [[Borophaginae|borophagine]] dogs.<ref name="bite"/><ref>{{Cite magazine|last=Switek|first=Brian|url=https://www.wired.com/2012/10/researchers-chew-over-a-prehistoric-bears-diet/|title=Researchers Chew Over a Prehistoric Bear's Diet|date=2012-10-29|magazine=Wired|access-date=2020-03-16|issn=1059-1028}}</ref>


Analysis of the teeth, jaw, and tooth wear patterns identifies ''Agriotherium'' as an [[omnivore]] that ate a lot of plant material. Though its teeth do not show adaptations for a carnivorous diet, isotope evidence suggests it did eat a significant amount of animal material, similar to some populations of modern [[brown bear]]s. Several studies of the skeleton, including a comparison with ''[[Hemicyon|Hemicyon ursinus]],'' a fossil bear widely accepted as a [[Predation|predator]], show that ''Agriotherium'' did not have the limb strength or speed needed for active hunting, either by ambush or by chasing down prey. It also did not show the long claws and increased forelimb strength typical of mammals that dig for food. These very large bears may have specialized on a combination of grazing, eating fruit and invertebrate food in season, and intimidating predators away from carcasses in order to scavenge meat and bone marrow.<ref>{{Cite journal|last=Sorkin|first=B.|date=January 2006|title=Ecomorphology of the giant short-faced bears Agriotherium and Arctodus|url=http://www.tandfonline.com/doi/abs/10.1080/08912960500476366|journal=Historical Biology|language=en|volume=18|issue=1|pages=1–20|doi=10.1080/08912960500476366|s2cid=85301983|issn=0891-2963}}</ref>
Analysis of the teeth, jaw, and tooth wear patterns identifies ''Agriotherium'' as an [[omnivore]] that ate a lot of plant material. Though its teeth do not show adaptations for a carnivorous diet, isotope evidence suggests it did eat a significant amount of animal material, similar to some populations of modern [[brown bear]]s. Several studies of the skeleton, including a comparison with ''[[Hemicyon|Hemicyon ursinus]],'' a fossil bear widely accepted as a [[Predation|predator]], show that ''Agriotherium'' did not have the limb strength or speed needed for active hunting, either by ambush or by chasing down prey. It also did not show the long claws and increased forelimb strength typical of mammals that dig for food. These very large bears may have specialized on a combination of grazing, eating fruit and invertebrate food in season, and intimidating predators away from carcasses in order to scavenge meat and bone marrow.<ref>{{Cite journal|last=Sorkin|first=B.|date=January 2006|title=Ecomorphology of the giant short-faced bears Agriotherium and Arctodus|url=http://www.tandfonline.com/doi/abs/10.1080/08912960500476366|journal=Historical Biology|language=en|volume=18|issue=1|pages=1–20|doi=10.1080/08912960500476366|s2cid=85301983|issn=0891-2963}}</ref>


Very large size would have been necessary to steal and defend kills in environments dominated by some of the most powerful [[Hypercarnivore|carnivorous]] mammals that have ever lived, such as the [[Machairodontinae|sabertooth cat]] ''[[Amphimachairodus]]'', with whom it shared territory in both Afro-Eurasia and North America, and the bone-cracking [[Canidae|canid]] ''[[Epicyon]]'' and the massive feliform sabertooth ''[[Barbourofelis]]'', which it lived alongside in Texas, as evidenced by fossil deposits at Coffee Ranch.<ref>{{cite book|last=Antón|first=Mauricio|title=Sabertooth|date=2013|publisher=University of Indiana Press|location=Bloomington, Indiana|isbn=9780253010421|pages=53–54}}</ref><ref>{{cite book |last=Turner |first=Alan |year=1997 |title= The Big Cats and their fossil relatives|url=https://archive.org/details/bigcatstheirfoss00turn |url-access=limited |publisher= Columbia University Press|location=New York|isbn= 0-231-10228-3|page= [https://archive.org/details/bigcatstheirfoss00turn/page/n234 201]}}</ref>
Very large size would have been necessary to steal and defend kills in environments dominated by some of the most powerful [[Hypercarnivore|carnivorous]] mammals that have ever lived, such as the [[Machairodontinae|sabertooth cat]] ''[[Amphimachairodus]]'', with whom it shared territory in both Afro-Eurasia and North America, and the bone-cracking [[Canidae|canid]] ''[[Epicyon]]'' and the massive feliform sabertooth ''[[Barbourofelis]]'', which it lived alongside in Texas, as evidenced by fossil deposits at Coffee Ranch.<ref>{{cite book|last=Antón|first=Mauricio|title=Sabertooth|date=2013|publisher=University of Indiana Press|location=Bloomington, Indiana|isbn=9780253010421|pages=53–54}}</ref><ref>{{cite book |last=Turner |first=Alan |year=1997 |title= The Big Cats and their fossil relatives|url=https://archive.org/details/bigcatstheirfoss00turn |url-access=limited |publisher= Columbia University Press|location=New York|isbn= 0-231-10228-3|page= [https://archive.org/details/bigcatstheirfoss00turn/page/n234 201]}}</ref> Its name was made from the Greek for "wild beast".


==Fossil distribution==
==Fossil distribution==
Sites and age of specimens:
Sites and age of specimens:
*American Cyanimid Company site, [[Bone Valley Formation]], [[Polk County, Florida]] ~13.7—11.6 Ma.
*Venta del Moro, [[Spain]] ~9–5.3 Ma.
*Venta del Moro, [[Spain]] ~9–5.3 Ma.
*Lang. E Quarry, [[South Africa]] ~5.3–3.6 Ma.
*Lang. E Quarry, [[South Africa]] ~5.3–3.6 Ma.
*Carlin High Quarry, [[Elko County, Nevada]] ~23–5.3 Ma.
*Vialette, Haute Loire, [[France]] ~3.2–2.5 Ma.
*Vialette, Haute Loire, [[France]] ~3.2–2.5 Ma.
*Middle Awash, [[Ethiopia]] ~11.6–3.6 Ma.
*Middle Awash, [[Ethiopia]] ~11.6–3.6 Ma.


''Agriotherium'' ranged widely; fossils of four or more species have been found in [[Europe]], [[Myanmar]], [[China]], [[North America]] and [[South Africa]].<ref>{{Cite journal|last1=Ogino|first1=Shintaro|last2=Egi|first2=Naoko|last3=Zin-Maung-Maung-Thein|last4=Thaung-Htike|last5=Takai|first5=Masanaru|date=2011-08-10|title=New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar|url=http://www.sciencedirect.com/science/article/pii/S1367912011002185|journal=Journal of Asian Earth Sciences|series=Suture Zones and Geodynamic Processes|language=en|volume=42|issue=3|pages=408–414|doi=10.1016/j.jseaes.2011.05.017|bibcode=2011JAESc..42..408O|issn=1367-9120}}</ref> It is the only [[Bear|ursoid]] known to have colonized [[sub-Saharan Africa]].<ref name = "Howell">{{cite journal
''Agriotherium'' ranged widely; fossils of four or more species have been found in [[Europe]], [[India]], [[Myanmar]], [[China]], and [[South Africa]].<ref>{{Cite journal|last1=Ogino|first1=Shintaro|last2=Egi|first2=Naoko|last3=Zin-Maung-Maung-Thein|last4=Thaung-Htike|last5=Takai|first5=Masanaru|date=2011-08-10|title=New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar|url=http://www.sciencedirect.com/science/article/pii/S1367912011002185|journal=Journal of Asian Earth Sciences|series=Suture Zones and Geodynamic Processes|language=en|volume=42|issue=3|pages=408–414|doi=10.1016/j.jseaes.2011.05.017|bibcode=2011JAESc..42..408O|issn=1367-9120}}</ref> It is the only [[Bear|ursoid]] known to have colonized [[sub-Saharan Africa]].<ref name="Howell">{{cite journal
| last = Howell
| last = Howell
| first = F. Clark
| first = F. Clark
Line 56: Line 52:


==References==
==References==
{{Reflist}}
{{reflist}}


==Sources==
==Sources==
*{{cite journal | doi = 10.2307/1381124 | last1 = Dalquest | first1 = W. W. | title = Lower Jaw and Dentition of the Hemphillian Bear, Agriotherium (Ursidae), with the Description of a New Species | journal = Journal of Mammalogy | volume = 67 | issue = 4 | pages = 623–631 | jstor = 1381124 | year = 1986 }}
*{{cite journal | doi = 10.2307/1381124 | last1 = Dalquest | first1 = W. W. | title = Lower Jaw and Dentition of the Hemphillian Bear, Agriotherium (Ursidae), with the Description of a New Species | journal = Journal of Mammalogy | volume = 67 | issue = 4 | pages = 623–631 | jstor = 1381124 | year = 1986 }}
*{{cite journal | doi = 10.2307/1382830 | last1 = Miller | first1 = W. E. | last2 = Carranza-Castañeda | first2 = O. | last3 = Carranza-Castaneda | first3 = Oscar | title = Agriotherium schneideri from the Hemphillian of Central Mexico | journal = Journal of Mammalogy | volume = 77 | issue = 2 | pages = 568–577 | jstor = 1382830 | year = 1996 | doi-access = free }}
*{{cite journal | doi = 10.2307/1382830 | last1 = Miller | first1 = W. E. | last2 = Carranza-Castañeda | first2 = O. | last3 = Carranza-Castaneda | first3 = Oscar | title = Agriotherium schneideri from the Hemphillian of Central Mexico | journal = Journal of Mammalogy | volume = 77 | issue = 2 | pages = 568–577 | jstor = 1382830 | year = 1996 | doi-access = free }}
*{{cite journal | last1 = Petter | first1 = G. | last2 = Thomas | first2 = H. | year = 1986 | title = Les Agriotheriinae (Mammalia, Carnivora)néogènes de l'Ancien Monde presence du genre Indarctos dans la faune de Menacer (ex−Marceau), Algérie | journal = Geobios | volume = 19 | pages = 573–586 | doi=10.1016/s0016-6995(86)80055-9}}
*{{cite journal | last1 = Petter | first1 = G. | last2 = Thomas | first2 = H. | year = 1986 | title = Les Agriotheriinae (Mammalia, Carnivora)néogènes de l'Ancien Monde presence du genre Indarctos dans la faune de Menacer (ex−Marceau), Algérie | journal = Geobios | volume = 19 | issue = 5 | pages = 573–586 | doi=10.1016/s0016-6995(86)80055-9| bibcode = 1986Geobi..19..573P }}
*{{cite journal | last1 = Sorkin | first1 = B. | title = Ecomorphology of the giant short-faced bears Agriotherium and Arctodus | journal = Historical Biology | volume = 18 | pages = 1–20 | year = 2006 | doi = 10.1080/08912960500476366 | s2cid = 85301983 }}
*{{cite journal | last1 = Sorkin | first1 = B. | title = Ecomorphology of the giant short-faced bears Agriotherium and Arctodus | journal = Historical Biology | volume = 18 | pages = 1–20 | year = 2006 | doi = 10.1080/08912960500476366 | s2cid = 85301983 }}


==External links==
==External links==
*[https://www.science-art.com/image_result/?id=846&pagename=Agriotherium_Attacking_a_Sivatherium#.XGgzcS2ZOqA Illustration at ScienceArt]
*[https://www.science-art.com/image_result/?id=846&pagename=Agriotherium_Attacking_a_Sivatherium#.XGgzcS2ZOqA Illustration at ScienceArt] {{Webarchive|url=https://web.archive.org/web/20190217030111/https://www.science-art.com/image_result/?id=846&pagename=Agriotherium_Attacking_a_Sivatherium#.XGgzcS2ZOqA |date=2019-02-17 }}


{{Ursidae extinct nav|state=collapsed}}
{{Ursidae extinct nav|state=collapsed}}
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[[Category:Miocene bears]]
[[Category:Miocene bears]]
[[Category:Pliocene bears]]
[[Category:Pliocene bears]]
[[Category:Miocene mammals of Africa]]
[[Category:Cenozoic mammals of Europe]]
[[Category:Pliocene mammals of Africa]]
[[Category:Cenozoic mammals of Africa]]
[[Category:Pleistocene mammals of Africa]]
[[Category:Cenozoic mammals of Asia]]
[[Category:Miocene mammals of North America]]
[[Category:Cenozoic mammals of North America]]
[[Category:Prehistoric placental genera]]
[[Category:Prehistoric carnivoran genera]]
[[Category:Pleistocene bears]]
[[Category:Pleistocene bears]]
[[Category:Pleistocene carnivorans]]
[[Category:Pleistocene carnivorans]]
[[Category:Pleistocene extinctions]]
[[Category:Pleistocene extinctions]]
[[Category:Fossil taxa described in 1837]]
[[Category:Fossil taxa described in 1837]]
[[Category:Ailuropodinae]]

Latest revision as of 06:17, 18 November 2024

Agriotherium
Temporal range: 13.6–2.5 Ma
Views of skull
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ursidae
Tribe: †Agriotheriini
Genus: †Agriotherium
Wagner, 1837
Type species
†Ursus sivalensis
(= †Agriotherium sivalensis)
Falconer & Cautley, 1836
Species[1]

†A. myanmarensis (Ogino et al., 2011)
†A. insigne (Gervais, 1859)
†A. inexpetans (Qiu et al., 1991)
†A. palaeindicus (Lydekker, 1878)
†A. sivalensis (Falconer & Cautley, 1836)
†A. africanum (Hendey, 1972)
†A. hendeyi Jiangzuo and Flynn, 2019

Agriotherium is an extinct genus of bears whose fossils are found in Miocene through Pleistocene-aged strata of North America, Eurasia, and Africa. This long-lived genus persisted from at least ~11.6–2.5 Mya.[2] Materials from the late-surviving A. africanum in Africa have suggested that A. africanum died out during the early Gelasian.[3]

Description and diet

[edit]
Mandible

A. africanum measured around 2 metres (7 ft) in body length and weighed up to 750 kilograms (1,650 lb),[4][5] making it larger than most living bears; however, mass estimates vary, with further studies presenting a lower mass estimate of 317–540 kilograms (699–1,190 lb).[6][7] Along with other large bears such as the cave bear, short-faced bears Arctodus and Arctotherium, and an extinct subspecies of the modern polar bear Ursus maritimus tyrannus, Agriotherium was among the largest known terrestrial members of Carnivora. They had longer legs and shorter faces than other bears, and were more lightly built. Their wide, short jaws could generate enormous bite force. It is not certain how this force was used by the living animal; a study designed to determine how the genus fed discovered that among living bears, the lowest bite force belongs to the predatory polar bear, which feeds largely on blubber, and the highest bite force belongs to the giant panda, a herbivore which uses it to crush bamboo. Shortened jaws with high bite forces are found in other mammals like Gelada baboons that eat grasses but evolved from non-grazing ancestors, and in bone-crushing scavengers, like spotted hyenas and borophagine dogs.[6][8]

Analysis of the teeth, jaw, and tooth wear patterns identifies Agriotherium as an omnivore that ate a lot of plant material. Though its teeth do not show adaptations for a carnivorous diet, isotope evidence suggests it did eat a significant amount of animal material, similar to some populations of modern brown bears. Several studies of the skeleton, including a comparison with Hemicyon ursinus, a fossil bear widely accepted as a predator, show that Agriotherium did not have the limb strength or speed needed for active hunting, either by ambush or by chasing down prey. It also did not show the long claws and increased forelimb strength typical of mammals that dig for food. These very large bears may have specialized on a combination of grazing, eating fruit and invertebrate food in season, and intimidating predators away from carcasses in order to scavenge meat and bone marrow.[9]

Very large size would have been necessary to steal and defend kills in environments dominated by some of the most powerful carnivorous mammals that have ever lived, such as the sabertooth cat Amphimachairodus, with whom it shared territory in both Afro-Eurasia and North America, and the bone-cracking canid Epicyon and the massive feliform sabertooth Barbourofelis, which it lived alongside in Texas, as evidenced by fossil deposits at Coffee Ranch.[10][11] Its name was made from the Greek for "wild beast".

Fossil distribution

[edit]

Sites and age of specimens:

  • Venta del Moro, Spain ~9–5.3 Ma.
  • Lang. E Quarry, South Africa ~5.3–3.6 Ma.
  • Vialette, Haute Loire, France ~3.2–2.5 Ma.
  • Middle Awash, Ethiopia ~11.6–3.6 Ma.

Agriotherium ranged widely; fossils of four or more species have been found in Europe, India, Myanmar, China, and South Africa.[12] It is the only ursoid known to have colonized sub-Saharan Africa.[13]

References

[edit]
  1. ^ Ogino, Shintaro, Naoko Egi, and Masanaru Takai. "New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar." Journal of Asian Earth Sciences 42.3 (2011): 408-414.
  2. ^ "Fossilworks: Agriotherium". fossilworks.org. Retrieved 17 December 2021.
  3. ^ "Fossilworks: Agriotherium africanum". fossilworks.org. Retrieved 17 December 2021.
  4. ^ Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 217. ISBN 1-84028-152-9.
  5. ^ Burness, G. P., Diamond, J., & Flannery, T. (2001). Dinosaurs, dragons, and dwarfs: The evolution of maximal body size. Proceedings of the National Academy of Sciences, 98(25), 14518–14523. https://doi.org/10.1073/pnas.251548698
  6. ^ a b Oldfield, C. C.; McHenry, C. R.; Clausen, P. D.; Chamoli, U.; Parr, W. C. H.; Stynder, D. D.; Wroe, S. (2012). "Finite element analysis of ursid cranial mechanics and the prediction of feeding behaviour in the extinct giant Agriotherium africanum". Journal of Zoology. 286 (2): 171. doi:10.1111/j.1469-7998.2011.00862.x. ISSN 1469-7998.
  7. ^ Sorkin, B. (2006). Ecomorphology of the giant short-faced bears Agriotherium and Arctodus. Historical Biology, 18(1), 1–20. https://doi.org/10.1080/08912960500476366
  8. ^ Switek, Brian (2012-10-29). "Researchers Chew Over a Prehistoric Bear's Diet". Wired. ISSN 1059-1028. Retrieved 2020-03-16.
  9. ^ Sorkin, B. (January 2006). "Ecomorphology of the giant short-faced bears Agriotherium and Arctodus". Historical Biology. 18 (1): 1–20. doi:10.1080/08912960500476366. ISSN 0891-2963. S2CID 85301983.
  10. ^ Antón, Mauricio (2013). Sabertooth. Bloomington, Indiana: University of Indiana Press. pp. 53–54. ISBN 9780253010421.
  11. ^ Turner, Alan (1997). The Big Cats and their fossil relatives. New York: Columbia University Press. p. 201. ISBN 0-231-10228-3.
  12. ^ Ogino, Shintaro; Egi, Naoko; Zin-Maung-Maung-Thein; Thaung-Htike; Takai, Masanaru (2011-08-10). "New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar". Journal of Asian Earth Sciences. Suture Zones and Geodynamic Processes. 42 (3): 408–414. Bibcode:2011JAESc..42..408O. doi:10.1016/j.jseaes.2011.05.017. ISSN 1367-9120.
  13. ^ Howell, F. Clark; Garcia, Nuria (December 2007). "Carnivora (Mammalia) From Lemudong'o (Late Miocene: Narok District, Kenya)" (PDF). Kirtlandia. 556. Cleveland Museum of Natural History: 121–139. Retrieved 2009-10-15.

Sources

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