|
Archaeocyon Head Restoration
''Archaeocyon'' ("ancient dog") is an extinct genus of the Borophaginae subfamily of canids native to North America. It lived during the Oligocene epoch 32-24 Ma., existing for approximately . Species of ''Archaeocyon'' are among the earliest known borophagines, although a species of ''Otarocyon'' has a slightly earlier first appearance. Fossils have been found across the northern Great Plains and along the west coast of North America. ''Archaeocyon'' was a comparatively small and unspecialized dog. Its dentition (teeth) suggests a slightly more hypocarnivorous (omnivorous) diet than the otherwise similar ''Hesperocyon''. The skeleton is also generalized, lacking specializations for running and retaining a plantigrade foot posture. A few derived features of the dentition support a relationship to Borophaginae and Caninae (the subfamily that includes living canids), rather than to the basal canid subfamily Hesperocyoninae. The temporal position of ''Archaeocyon'' suggests an af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borophaginae
The extinct Borophaginae form one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Hesperocyoninae and extant Caninae. Borophaginae, called "bone-crushing dogs", were endemic to North America during the Oligocene to Pliocene and lived roughly 34—2.5 million years ago, existing for about . Origin The Borophaginae descended from the subfamily Hesperocyoninae. The earliest and most primitive borophagine is the genus ''Archaeocyon'', which is a small fox-sized animal mostly found in the fossil beds in western North America. The borophagines soon diversified into several major groups. They evolved to become considerably larger than their predecessors, and filled a wide range of niches in late Cenozoic North America, from small omnivores to powerful, bear-sized carnivores, such as ''Epicyon''. Species There are 66 identified borophagine species, including 18 new ones that range from the Orellan to Blancan ages. A phylogenetic anal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plantigrade
151px, Portion of a human skeleton, showing plantigrade habit In terrestrial animals, plantigrade locomotion means walking with the toes and metatarsals flat on the ground. It is one of three forms of locomotion adopted by terrestrial mammals. The other options are digitigrade, walking on the toes with the heel and wrist permanently raised, and unguligrade, walking on the nail or nails of the toes (the hoof) with the heel/wrist and the digits permanently raised. The leg of a plantigrade mammal includes the bones of the upper leg (femur/humerus) and lower leg (tibia and fibula/radius and ulna). The leg of a digitigrade mammal also includes the metatarsals/metacarpals, the bones that in a human compose the arch of the foot and the palm of the hand. The leg of an unguligrade mammal also includes the phalanges, the finger and toe bones. Among extinct animals, most early mammals such as pantodonts were plantigrade. A plantigrade foot is the primitive condition for mammals; digit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene Mammals Of North America
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene Canids
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the front ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperocyoninae
The extinct Hesperocyoninae are one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Borophaginae and extant Caninae. Taxonomic history Hesperocyoninae are basal canids that gave rise to the other two canid subfamilies, the Borophaginae and Caninae. This subfamily was endemic to North America, living from the Duchesnean stage of the Late Eocene through to the early Barstovian stage of the Miocene, lasting around 20 million years. It comprises 10 recognized genera and 26 recognized species. Four major lineages can be defined based on shared characteristics: *''Mesocyon''-''Enhydrocyon'' clade (includes ''Cynodesmus, Sunkahetanka, Philotrox'') *''Osbornodon'' clade *'' Paraenhydrocyon'' *'' Ectopocynus clade'' The genus ''Caedocyon'', which is only known from a single partial cranium that shows some ''Paraenhydrocyon'' affinities, probably represents another independent lineage. ''Hesperocyon'', which lacks the shared derived c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caninae
The Caninae, known as canines, are one of three subfamily, subfamilies found within the Canidae, canid family. The other two canid subfamilies are the extinct Borophaginae and Hesperocyoninae. The Caninae includes all living canids and their most recent fossil relatives. Their fossils were first found in North America and dated to the Oligocene era, then spreading to Asia at the end of the Miocene era, some 7 million to 8 million years ago. Taxonomy and lineage The genus ''Leptocyon'' (Greek: ''leptos'' slender + ''cyon'' dog) includes 11 species and was the first primitive canine. They were small and weighed around 2 kg. They first appeared in Sioux County, Nebraska in the Orellan era 34-32 million years ago, which was the beginning of the Oligocene. This was the same time as the appearance of the Borophaginae with whom they share features, indicating that these were two sister groups. Borophaginae skull and dentition were designed for a powerful killi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperocyon
''Hesperocyon'' is an extinct genus of canids (subfamily Hesperocyoninae, family Canidae) that was endemic to North America, ranging from southern Canada to Colorado. It appeared during the Uintan age, – Bridgerian age (NALMA) of the Mid-Eocene– 42.5 Ma to 31.0 Ma. ( AEO). ''Hesperocyon'' existed for approximately . Taxonomy ''Hesperocyon'' was assigned to Borophagini by Wang et al. in 1999 and was the earliest of the canids to evolve after the Caniformia-Feliformia split some 42 million years ago. Fossil evidence dates ''Hesperocyon gregarius'' to at least 37 mya, but the oldest ''Hesperocyon'' has been dated at 39.74 mya from the Duchesnean North American land mammal age. The Canidae subfamily Hesperocyoninae probably arose out of ''Hesperocyon'' to become the first of the three great dogs groups: Hesperocyoninae (~40–30 Ma), Borophaginae (~36–2 Ma), and the Caninae lineage that led to the present-day canids (including grey wolves, foxes, coyotes, jackals and dogs). A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canid
Canidae (; from Latin, ''canis'', "dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within the canid family, which are the extinct Borophaginae and Hesperocyoninae, and the extant Caninae. The Caninae are known as canines, and include domestic dogs, wolves, coyotes, foxes, jackals and other extant and extinct species. Canids are found on all continents except Antarctica, having arrived independently or accompanied human beings over extended periods of time. Canids vary in size from the gray wolf to the fennec fox. The body forms of canids are similar, typically having long muzzles, upright ears, teeth adapted for cracking bones and slicing flesh, long legs, and bushy tails. They are mostly social animals, living together in family units or small groups and behaving cooperatively. Typically, only the dominant pair in a group breed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutrients and energy of the sources absorbed. Often, they have the ability to incorporate food sources such as algae, fungi, and bacteria into their diet. Omnivores come from diverse backgrounds that often independently evolved sophisticated consumption capabilities. For instance, dogs evolved from primarily carnivorous organisms (Carnivora) while pigs evolved from primarily herbivorous organisms (Artiodactyla). Despite this, physical characteristics such as tooth morphology may be reliable indicators of diet in mammals, with such morphological adaptation having been observed in bears. The variety of different animals that are classified as omnivores can be placed into further sub-categories depending on their feeding behaviors. Frugivores ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypocarnivore
A hypocarnivore is an animal that consumes less than 30% meat for its diet, the majority of which consists of fungi, fruits, and other plant material. Examples of living hypocarnivores are the grizzly bear (''Ursus horribilis''), black bear (''Ursus americanus''), binturong (''Arctictis binturong''), kinkajou (''Potos flavus''), and humans (''Homo sapiens''). The evolutionary division of carnivory into three groups, including hypercarnivore and mesocarnivore, appears to have occurred about 40 million years ago (mya). The term hypocarnivory is used with increasing frequency in describing early Canidae evolution, and reliance upon that survival strategy has a documented history in North American Borophaginae during the Miocene (23.03 to 5.33 mya). Twenty-five species of hypocarnivore are documented as co-occurring on the North American continent 30 mya. A shift from hyper- to hypo- occurred at least three times among Oligocene and Miocene canids ''Oxetocyon'', ''Phlaocyon'', and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Borophaginae")
.png "Click for more on -> Caninae")
.jpg "Click for more on -> Canid")
