23-443: Poebrotherium ( / ˌ p oʊ b r oʊ ˈ θ ɪər i əm / POH -broh- THEER -ee-əm ) is an extinct genus of camelid , endemic to North America . They lived from the Eocene to Miocene epochs, 46.3—13.6 mya , existing for approximately 32 million years . Poebrotherium was first named by scientist Joseph Leidy in 1848, and its relationship to other White River fossils
46-445: A pes lacking digits 1, 4, and 5; and a typical ungulate stance but lacking in a foot pad. Camelidae Camelids are members of the biological family Camelidae , the only currently living family in the suborder Tylopoda . The seven extant members of this group are: dromedary camels , Bactrian camels , wild Bactrian camels , llamas , alpacas , vicuñas , and guanacos . Camelids are even-toed ungulates classified in
69-628: A result of changing environmental conditions after the last ice age, or a combination of these factors. Three species groups survived - the dromedary of northern Africa and southwest Asia; the Bactrian camel of central Asia; and the South American group, which has now diverged into a range of forms that are closely related, but usually classified as four species - llamas , alpacas , guanacos , and vicuñas . Camelids were domesticated by early Andean peoples, and remain in use today. Fossil camelids show
92-404: A unique type of antibodies , which lack the light chain, in addition to the normal antibodies found in other mammals. These so-called heavy-chain antibodies are being used to develop single-domain antibodies with potential pharmaceutical applications. Camelids do not have hooves; rather, they have two-toed feet with toenails and soft foot pads ( Tylopoda is Greek for "padded foot"). Most of
115-443: A wider variety than their modern counterparts. One North American genus, Titanotylopus , stood 3.5 m at the shoulder, compared with about 2.0 m for the largest modern camelids. Other extinct camelids included small, gazelle-like animals, such as Stenomylus . Finally, a number of very tall, giraffe-like camelids were adapted to feeding on leaves from high trees, including such genera as Aepycamelus and Oxydactylus . Whether
138-419: Is almost the inverse of their area of origin. Camelids first appeared very early in the evolution of the even-toed ungulates, around 50 to 40 million years ago during the middle Eocene , in present-day North America. Among the earliest camelids was the rabbit-sized Protylopus , which still had four toes on each foot. By the late Eocene , around 35 million years ago, camelids such as Poebrotherium had lost
161-505: Is likely that Poebrotherium was either a browser or a mixed-feeder, and grass may have played a minimal role in the diet of Poebrotherium . Unlike its modern cousins, which are either adapted for desert or alpine conditions, Poebrotherium took the place of a gazelle or deer in the White River Fauna ecosystem. This trait was taken to an extreme in later camels, notably Stenomylus . Fossil evidence has shown that Poebrotherium
184-469: Is the Latinised name of a person or place, or a Latin adjective denoting a postulated characteristic of the species. Poebrotherium looked more like modern camels than its predecessor Protylopus , but at 90 centimetres (3.0 ft) in height, it was roughly the size of a modern sheep . Its skull resembled that of a modern llama , while its limbs ended in hooved toes and were more built for speed than
207-486: The Camelinae proper. In fact the definition of Camelidae is the most recent common ancestor of Poebrotherium and Camelus , and all of its descendants. Several authors offer characteristics to define Poebrotherium . These include a long neck; an adult height of around 100 centimetres (3.3 ft); relatively unspecialized teeth; moderately long legs; long, unsplayed, unfused, and proximally wider-than-deep metapodials ;
230-568: The Great American Interchange ), giving rise to the modern llamas. A population of Paracamelus continued living in North America and evolved into the high arctic camel , which survived until the middle Pleistocene. The original camelids of North America remained common until the quite recent geological past, but then disappeared, possibly as a result of hunting or habitat alterations by the earliest human settlers , and possibly as
253-722: The molars by a gap. As in ruminants, the upper incisors are largely absent and are replaced by a dental pad consisting of connective tissue covered with epithelium . The musculature of the hind limbs differs from those of other ungulates in that the legs are attached to the body only at the top of the thigh, rather than attached by skin and muscle from the knee upwards. Because of this, camelids have to lie down by resting on their knees with their legs tucked underneath their bodies. They have three-chambered stomachs , rather than four-chambered ones; their upper lips are split in two, with each part separately mobile; and, uniquely among mammals, their red blood cells are elliptical. They also have
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#1732855020105276-484: The order Artiodactyla , along with species including whales , pigs , deer , cattle , and antelopes . Camelids are large, strictly herbivorous animals with slender necks and long legs. They differ from ruminants in a number of ways. Their dentition show traces of vestigial central incisors in the incisive bone , and the third incisors have developed into canine-like tusks. Camelids also have true canine teeth and tusk-like premolars , which are separated from
299-529: The American Museum west to expand his collection. Between 1848 and 1853, cases of new material were shipping back to Leidy. Maddeningly, only three more Poebrotherium tooth samples were among the remains recovered. The term poebrotherium comes from Ancient Greek : ποιηβόρος ( poiēbóros , "grass-eating") and θηρίον ( thēríon , "wild animal; animal; "beast"), in Latinised form. The specific epithet
322-609: The Bactrian camel are even able to drink brackish water , and some herds live in nuclear test areas. Comparative table of the seven extant species in the family Camelidae: ( Camelus bactrianus ) ( Camelus dromedarius ) ( Camelus ferus ) ( Lama glama ) ( Lama guanicoe ) ( Lama pacos ) ( Lama vicugna ) L. glama L. guanicoe V. vicugna V. pacos C. bactrianus C. dromedarius C. kansanus C. hesternus C. minodokae Camelids are unusual in that their modern distribution
345-400: The feet of Protylopus . Despite this apparent adaptation to the open plains, Poebrotherium has been found in all major White River environments, including forests and river overbank deposits, indicating that it was not tied to one particular environment. The teeth of Poebrotherium were more generalised than those of modern camelids. In fact, despite the name meaning "grass-eating beast" it
368-444: The foot. Many fossil camelids were unguligrade and probably hooved, in contrast to all living species. Camelids are behaviorally similar in many ways, including their walking gait, in which both legs on the same side are moved simultaneously. While running, camelids engage a unique "running pace gait" in which limbs on the same side move in the same pattern they walk, with both left legs moving and then both right, which ensures that
391-473: The fore and hind limb will not collide while in fast motion. During this motion, all four limbs momentarily are off the ground at the same time. Consequently, camelids large enough for human beings to ride have a typical swaying motion. Dromedary camels, bactrian camels, llamas, and alpacas are all induced ovulators . The three Afro-Asian camel species have developed extensive adaptations to their lives in harsh, near-waterless environments. Wild populations of
414-603: The two lateral toes, and were about the size of a modern goat . The family diversified and prospered, with the two living tribes, the Camelini and Lamini , diverging in the late early Miocene , about 17 million years ago, but remained restricted to North America until about 6 million years ago, when Paracamelus crossed the Bering land bridge into Eurasia , giving rise to the modern camels, and about 3-2 million years ago, when Hemiauchenia emigrated into South America (as part of
437-425: The weight of the animal rests on these tough, leathery sole pads. The South American camelids have adapted to the steep and rocky terrain by adjusting the pads on their toes to maintain grip. The surface area of Camels foot pads can increase with increasing velocity in order to reduce pressure on the feet and larger members of the camelid species will usually have larger pad area, which helps to distribute weight across
460-728: The wild Bactrian camel ( Camelus ferus ) is a distinct species or a subspecies ( C. bactrianus ferus ) is still debated. The divergence date is 0.7 million years ago, long before the start of domestication. Family Camelidae Lama guanicoe Lama glama Lama pacos Lama vicugna Bactrian camel Dromedary In October 2017 the United Nations declared 2024 to be the International Year of Camelids in order to show how camelids are important for food security, economics and culture for many pastoral communities. Metapodials Metapodials are long bones of
483-588: Was a popular prey item for the entelodont Archaeotherium . Remains of partial Poebrotherium carcasses have been found fossilized, and appear to have been killed and cached by Archaeotherium , the only animal known from the White River ecosystem that could have made the feeding marks found on the bones of Poebrotherium . Poebrotherium lies within the clade Camelidae , which can be defined as ( Stenomylinae + ( Miolabinae + ( Protolabinae + Camelinae ))) + Poebrotherium . As such, Poebrotherium lies outside
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#1732855020105506-466: Was later expanded by him in 1853. Fur trapper Samuel Culbertson was working in Nebraska in pursuit of fur bearing mammals, and found a collection of strange fossil animal bones. He sent a box of these bones to his family back east, and not knowing what to make of them, they forwarded the remains to Leidy for identification. Several animals' remains were included in this package, but one of the most interesting
529-446: Was that of a small mammal, about the size of a small deer or sheep. In addition to a partial skull, a portion of a forelimb was found. The portions that Leidy was able to examine helped him determine it was likely related to modern llamas , even though there was a paucity of new material available after his 1848 diagnosis. This package spawned Leidy's interest in the White River badlands and its fauna, and he eventually sent collectors from
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