Agriotherium
| Agriotherium Temporal range: Late Miocene–Pleistocene | |
|---|---|
 | |
| Teeth | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Superfamily: | Arctoidea |
| Family: | Ursidae |
| Subfamily: | †Agriotheriinae[1] Kretzoi, 1929 |
| Genus: | †Agriotherium Wagner, 1837 |
| Type species | |
| †Agriotherium sivalensis Falconer & Cautley, 1836 | |
| Species[2] | |
|
†A. myanmarensis (Ogino et al., 2011) | |
Agriotherium is an extinct genus of Ursidae of the Miocene through Pleistocene epochs, with fossils found in Neogene strata of North America, Europe, Africa, and Asia, living from ~13.6–2.5 Ma, existing for approximately 11.1 million years.
Morphology
Agriotherium was about 2.7 metres (9 ft) in body length and weighed around 652.6 kg (1,440 lb), making it larger than most living bears. Except for the extinct subspecies of modern polar bear Ursus maritimus tyrannus and Arctotherium, Agriotherium was along with the short-faced bear, Arctodus simus the largest member of terrestrial Carnivora. It had dog-like crushing teeth. Its primary diet was carnivorous and secondary was omnivorous possibly classifying this animal as mesocarnivore. With a body mass close to those of most large ungulates (bovines, cervids, camelids, and others), it is probable that Agrotherium could have preyed on these.
Body mass
Two specimens were examined by Legendre and Roth for body mass.[3]
- Specimen 1: 79.3 kg (175 lb)
- Specimen 2: 652.6 kg (1,440 lb)
Bite strength
A 2011 estimate that compared the bites of a few selected bears, both extant and extinct, concluded that Agriotherium had the strongest bite-force of any mammalian land-predator yet estimated.[4]
Fossil distribution
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.
- 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.
- Middle Awash, Ethiopia ~11.6–3.6 Ma.
Agriotherium ranged widely; fossils of four or more species have been found in Europe, India, China, North America and South Africa. It is the only ursoid known to have colonized sub-Saharan Africa (amphicyonid "bear dogs" also reached the area).[5]
References
- ↑ McLellan, Bruce, and David C. Reiner. "A review of bear evolution." Bears: Their Biology and Management (1994): 85-96.
- ↑ 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.
- ↑ S. Legendre and C. Roth. 1988. Correlation of carnassial tooth size and body weight in recent carnivores (Mammalia). Historical Biology 1(1):85–98
- ↑ "Ancient bear had the strongest bite". BBC News.
- ↑ Howell, F. Clark; Garcia, Nuria (December 2007). "Carnivora (Mammalia) From Lemudong'o (Late Miocene: Narok District, Kenya)" (PDF). Kirtlandia. Cleveland Museum of Natural History. 556: 121–139. Retrieved 2009-10-15.
Sources
- Dalquest, W. W. (1986). "Lower Jaw and Dentition of the Hemphillian Bear, Agriotherium (Ursidae), with the Description of a New Species". Journal of Mammalogy. 67 (4): 623–631. doi:10.2307/1381124. JSTOR 1381124.
- Miller, W. E.; Carranza-Castañeda, O.; Carranza-Castaneda, Oscar (1996). "Agriotherium schneideri from the Hemphillian of Central Mexico". Journal of Mammalogy. 77 (2): 568–577. doi:10.2307/1382830. JSTOR 1382830.
- Petter, G.; Thomas, H. (1986). "Les Agriotheriinae (Mammalia, Carnivora)néogènes de l'Ancien Monde presence du genre Indarctos dans la faune de Menacer (ex−Marceau), Algérie". Geobios. 19: 573–586. doi:10.1016/s0016-6995(86)80055-9.
- Sorkin, B. (2006). "Ecomorphology of the giant short-faced bears Agriotherium and Arctodus". Historical Biology: A Journal of Paleobiology. 18: 1–20. doi:10.1080/08912960500476366.