Daeodon

Quality 0.50 · 0 views · Updated 2 months ago

Extinct genus of mammals

title: "Daeodon" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["entelodonts", "miocene-artiodactyla", "miocene-mammals-of-north-america", "oligocene-mammals-of-north-america", "arikareean", "hemingfordian", "white-river-fauna", "burdigalian-genus-extinctions", "chattian-genus-first-appearances", "fossil-taxa-described-in-1878", "taxa-named-by-edward-drinker-cope", "prehistoric-artiodactyla-genera", "oligocene-artiodactyla"] description: "Extinct genus of mammals" topic_path: "general/entelodonts" source: "https://en.wikipedia.org/wiki/Daeodon" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct genus of mammals ::

D. humerosum? Cope, 1879 | synonyms = {{species list | Boochoerus|Cope, 1879 | Ammodon|Marsh, 1893 | Dinohyus|Peterson, 1905b}} ::figure[src="https://upload.wikimedia.org/wikipedia/commons/1/1c/Daeodon_shoshonensis_.png" caption="''Daeodon shoshonensis'' life restoration"] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/a/a0/Dinohyus_hollandi_(fossil_mammal)Lower_Miocene_of_Nebraska.jpg" caption="Agate Springs Fossil Quarry]] in Nebraska. See text for nomenclature history"] ::

Daeodon is an extinct genus of entelodont even-toed ungulates that inhabited North America about 29 to 15.97 million years ago from the early Oligocene to late early Miocene. The type species is Daeodon shoshonensis, described from a very fragmentary holotype by Cope. Some authors synonymize it with Dinohyus hollandi and several other species (see below), but due to the lack of diagnostic material, this may be questionable.

Another large member of this family, possibly larger than Daeodon, is the Asian Paraentelodon, but it is known by very incomplete material. | isbn = | url = https://books.google.com/books?id=MOEtAQAAIAAJ&q=Бенарская+фауна+олигоценовых+позвоночных | title = Бернарская фауна олигоценовых позвоночных (The Benarskaya Fauna of Oligocene Vertebrates) | publisher = Metsniereba, Tbilisi | date = 1964 | access-date = 2020-09-26 | quote = | pages = 109–133 | author = L. K. Gabunia

Taxonomy

The genus Daeodon was erected by the American anatomist and paleontologist Edward Drinker Cope in 1878. He classified it as a perissodactyl and thought that it was closely related to Menodus. This classification persisted until the description of "Elotherium" calkinsi in 1905, a very similar and much more complete animal from the same rocks, which was promptly assigned as a species of Dynohyus by Peterson (1909). Although not specified in Cope's original description, the name Daeodon comes from the Greek words grc, meaning "hostile" or "dreadful" and grc, meaning "teeth".

Species

The type species of Daeodon is D. shoshonensis, which is based on a fragment of a lower jaw from the John Day Formation of Oregon. Several other species were assigned to the genus in the subsequent decades, like D. calkinsi, D. mento and D. minor. Since 1945, it had been suggested that two other taxa were actually junior synonyms of Daeodon, but the formalization of this referral didn't take place until the work of Lucas et al. (1998). a complete skeleton from the Agate Springs quarry of Nebraska, were found to be indistinguishable from each other and in turn both were indistinguishable from D. shoshonensis.

Description

::figure[src="https://upload.wikimedia.org/wikipedia/commons/8/8c/Daeodon_shoshonensis_skeletal.jpg" caption="Skeletal restoration"] ::

Daeodon shoshonensis is the largest-known entelodont; known adult individuals had skulls about 90 cm long and were about 1.77 m tall at the shoulders, with large males estimated to have weighed at least 750 kg. Daeodon is differentiated from other entelodonts by a suite of unique dental characters, the shape and relatively small size of the cheekbone flanges of its skull compared to those of Archaeotherium, and the small size of its chin tubercle, as well as features of its carpus and tarsus and the fusion of the bones of the lower leg.

Paleoecology

Habitat

Daeodon had a wide range in North America, with many fossils found in Agate Fossil Beds, representing an environment in a transition period between dense forests and expansive prairie, likely a major cause of their extinction in the early Miocene. It adapted to the grassland with a more cursorial body plan than more basal entelodonts like Archaeotherium, losing their dewclaws entirely, proximally fused metacarpals, and similar shoulder musculature to bison.

The Agate Springs bonebed was a floodplain environment with wet and dry seasons. Daeodon shared this landscape with small gazelle-like camels Stenomylus, the large browsing chalicothere Moropus, several species of predatory coyote- to wolf-sized amphicyonids that lived in packs, land beavers (Palaeocastor) that filled the ecological niche of modern prairie dogs, and thousands of small herd-living rhinoceros. The rhinos suffered massive periodic die-offs in the dry season, but Daeodon fossils are rare, which suggests they were neither social animals nor especially attracted to carrion.

Diet

Daeodon was omnivorous like all other entelodonts. Enamel patterns suggest eating of nuts, roots, and vines, as well as meat and bones. The superficial similarity to peccaries, hippos, and bears implies a wide range in terms of what plants Daeodon may have been eating. The dry seasons of North America at the time could get very harsh, so they may have supplemented their water intake by eating grape vines. The extent of its carnivory is debated, but tooth wear suggests they specialized in crushing bone and ripping meat, and bite marks on chalicothere bones suggest they either hunted or scavenged large herbivores. Foss (2001) argues its head was far too heavy to be effective in taking down large prey so it must have relied exclusively on scavenging, but its bison-like adaptations for running, the stereoscopic vision characteristic of predators, and evidence of predation in entelodonts calls this interpretation into question. The uncertainty of their diets suggests they were likely opportunistic omnivores similar to bears, eating whatever they needed depending on the circumstance.

Behavior

Entelodonts partook in intraspecific face biting, known from tooth marks on their skulls. Males would fight for dominance, possibly using their mandibular tubercles as protection in addition to their function as muscle attachments. Sexual dimorphism of the jugal protections exist in Archaeotherium, and with a smaller Daeodon sample size, such dimorphism can't be ruled out for Daeodon. If dimorphic, the function of the expanded jugals was likely for display, supporting large preorbital glands similar to those forest hogs possessed for chemical communication.

References

Donald R. Prothero. (2007). "The Evolution of Artiodactyls". JHU Press.
Cope, E. D.. (1878). "On some characters of the Miocene fauna of Oregon". Paleontological Bulletin.
Sinclair, W. J.. (1905). "New and imperfectly known rodents and ungulates from the John Day Series". Bull. Dept. Geology, Univ. California.
Foss, S. E.. (2001). "Biostratigraphy of the Entelodontidae (Mammalia: Artiodactyla) from the John Day Basin, Oregon". PaleoBios.
(1977). "Composition of Scientific Words : A manual of methods and a lexicon of materials for the practice of logotechnics". Smithsonian Institutional Press.
Allen, G. M.. (1926). "Fossil mammals from South Carolina". Bulletin of the Museum of Comparative Zoology.
Loomis, F. B.. (1932). "Two new Miocene entelodonts.". Journal of Mammalogy.
Simpon, G. G.. (1945). "The principles of classification and a classification of mammals.". Bulletin of the American Museum of Natural History.
Peterson, O. A.. (1905b). "A correction of the generic name (Dinochoerus) given to certain fossil remains from the Loup Fork Miocene of Nebraska". Science.
Peterson, O. A.. (1905a). "Preliminary note on a gigantic mammal from the Loup Fork Beds of Nebraska". Science.
(1998). "Taxonomy and distribution of ''Daeodon'', an Oligocene-Miocene entelodont (Mammalia: Artiodactyla) from North America". Proceedings of the Biological Society of Washington.
Joeckel, R. M.. (1990). "A Functional Interpretation of the Masticatory System and Paleoecology of Entelodonts". Paleobiology.
Peterson, O. A.. (1909). "A revision of the Entelodontidae". Memoirs of the Carnegie Museum.
Effinger, J. A.. (1998). "Evolution of Tertiary Mammals of North America. Volume 1: Terrestrial Carnivores, Ungulates, and Ungulatelike Mammals.". Cambridge University Press.
[http://npshistory.com/publications/agfo/nrr-2009-080.pdf Agate Fossil Beds National Monument] National Park Service. 2009
Andrew Brant Clifford. (May 2010). "Evolution and Mechanics of Unguligrady in Artiodactyls".
"Mammal Fossils - Agate Fossil Beds National Monument (U.S. National Park Service)".
(1999). "Abstract of Papers. Fifty-ninth Annual Meeting Society of Vertebrate Paleontology". Journal of Vertebrate Paleontology.
Foss, S. E., 2001, Systematics and paleobiology of the Entelodontidae (Mammalia, Artiodactyla) [Ph.D. dissertation]: Dekalb, Northern Illinois University

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::