Note the length of the teeth, which grow continuously. The chewing faces of the teeth aren't completely covered with enamel. As the teeth wear down, they expose layers of hard enamel and softer dentin. As the dentin wears faster than the enamel, the teeth continually show new sharp edges for chewing. The molars are similar to those of rodents or artiodactyls. Reference: These two species of giant beaver (genus Castoroides) are not close relatives to modern beavers (genus Castor). [5] This genus typifies the extinct subfamily Castoroidinae, which forms a North American lineage beginning with the Hemingfordian genus Monosaulax, followed by Eucastor, Dipoides, and Procastoroides, to finally culminate and go extinct with Castoroides. [8] Discovery and species [ edit ] A cast of C. ohioensis assembled from various specimens Beavers are North America’s largest rodent and the second-largest living rodents after the capybara, which can be in South America. They weigh between 35 and 65 pounds, with the heaviest beaver on record weighing 110 pounds. They are 3 to 4 feet long and stand 1 to 1.5 feet tall. Appearance: Beavers are mainly nocturnal and crepuscular, and spend the daytime in their shelters. In northern latitudes, beaver activity is decoupled from the 24-hour cycle during the winter, and may last as long as 29 hours. They do not hibernate during winter, and spend much of their time in their lodges. [10] [24] [91] Family life Beaver skulls have huge areas for jaw muscles, and weird-looking ear tubes. LDUCZ-Z2731 What a cheek!

Up to four young, or kits, are born in spring and summer, after a three or four-month gestation. [31] [94] Newborn beavers are precocial with a full fur coat, and can open their eyes within days of birth. [24] [31] Their mother is the primary caretaker, while their father maintains the territory. [10] Older siblings from a previous litter also play a role. [95] North American beavers typically live 10 to 12 years and can live up to 30 years. The average lifespan of the Eurasian beaver is 7 to 8 years and can be up to 25 years. Threats: Harington, C.R. (1977). Pleistocene mammals of the Yukon Territory (Ph.D thesis). Edmonton: University of Alberta. 1060 pp.

Skull Terminology: Coyote

Mahoney, Michael J.; Stella, John C. (2020). "Stem size selectivity is stronger than species preferences for beaver, a central place forager". Forest Ecology and Management. 475: 118331. doi: 10.1016/j.foreco.2020.118331. S2CID 224922775. Martin, R.A. (1969). "Taxonomy of the giant Pleistocene beaver Castoroides from Florida". Journal of Paleontology. 43 (4): 1033–1041. Large, continuously growing molars with alternating layers of enamel and dentin on the biting surfaces. Kits generally leave their lodge after their first year, during which the mother usually stays with them while the father protects the territory. Beavers will defend their territory when necessary. After another year, beaver kits usually leave the home to mate and dam a territory of their own. Social Structure:

Beaver reintroduction in the UK". Royal Society for the Protection of Birds. Archived from the original on November 6, 2020 . Retrieved September 28, 2020. Large angle on mandible for attachment of the large masseter muscles that are used for sideways grinding of food. Unlike the Carnivora skulls, there is no hook-shaped angular process, just a large angle of the jaw.

Porcupine (Order Rodentia)

One of the defining characteristics of the giant beaver was their incisor teeth, which differed in size and shape from those of modern beavers. Modern beavers have incisors with smooth enamel, while the teeth of the giant beaver had a striated, textured enamel surface. [6] Their teeth were also much larger, up to 15cm (6in) long. [6] The brain of the giant beaver was proportionally smaller than the modern beaver. As a result, the giant beaver may have had inferior interactions in its environment, as well as less complex patterns of thoughts and behavior. [7] [ failed verification] Classification [ edit ] Game animals not only provide pelts and meat, but they can also provide great home decoration. Recently I decided to clean and preserve a beaver skull from a 51 pounder that was caught this year. Cleaning skulls for presentation is really pretty easy. You just need to set aside some time to do it. The next time you have a memorable catch or hunt, consider preserving the animal’s skull for a great looking decorative piece. Huget, Jennifer LaRue (September 6, 2012). "Beavers and rabies". The Washington Post. Archived from the original on October 23, 2020 . Retrieved October 20, 2020.

Barisone, G.; Argenti, P.; Kotsakis, T. (2006). "Plio-Pleistocene evolution of the genus Castor (Rodentia, Mammalia) in Europe: C. fiber plicidens of Pietrafitta (Perugia, Central Italy)". Geobios. 39 (6): 757–770. Bibcode: 2006Geobi..39..757B. doi: 10.1016/j.geobios.2005.10.004. Hunt, Kate (June 30, 2020). "Beavers are gnawing away at the Arctic permafrost, and that's bad for the planet". CNN . Retrieved March 11, 2021.

Beaver skulls and teeth are disproportionately large. This is crucial for cutting through hard woods like maple and oak. Most noteably, the upper incisors, bright orange in color, are at least 5 mm wide and 20-25 mm long. These teeth grow throughout the animal's lifetime and are a necessity to survival, just as the animal's closable nostrils, closable ears, and transparent eye membranes are for aquatic existence. ( Hall and Kelson, 1959; Whitaker and Hamilton, 1998)