The loss of both wetland habitats in lowland regions and associated mixed-conifer forests coincide with regional disappearances of Castoroides populations in North America. Castoroides populations were extirpated from different regions such as the southeast, Great Plains regions, and northern North America (Canada and Alaska) as a direct result of local glacial periods within the Last Glacial Maximum that brought aridification to the habitats and made them unsuitable. Radiocarbon dates from Ohio and New York indicate that the lowlands south of the Great Lakes was home to the last isolated Castoroides populations when it disappeared from eastern North America shortly before the Pleistocene-Holocene transition event, bringing the complete extinction of the genus. The youngest known Castoroides specimens from New York State overlap with human artifacts (dating to 10,150 ± 50 years BP uncalibrated, later estimated to range from 11,501 to 12,050 years BP in calibrated radiocarbon date), suggesting that it overlapped with Paleo-Indian populations for up to a thousand years. However, there is no zooarchaeological evidence that humans butchered, hunted, or used Castoroides as a resource. Although causes of extinction of the Great Lakes Basin population are not specifically known, potential competition for habitat space and climate change brought about their extinction. [27] [28] Interaction with humans [ edit ] a b c Cassola, F. (2016). " Castor canadensis". IUCN Red List of Threatened Species. 2016: e.T4003A22187946. doi: 10.2305/IUCN.UK.2016-3.RLTS.T4003A22187946.en.

a b c d Kurtén, B. and E. Anderson (1980). Pleistocene Mammals of North America. Columbia University Press. pp.236–237. ISBN 978-0-231-03733-4. Russel, K. R.; Moorman, C. E.; Edwards, J. K.; Guynn, D. C. (1999). "Amphibian and reptile communities associated with beaver ( Castor canadenis) ponds and unimpounded streams in the Piedmont of South Carolina". Journal of Freshwater Ecology. 14 (2): 149–158. doi: 10.1080/02705060.1999.9663666. Ruez, Dennis R, "Early Irvingtonian (Latest Pliocene) Rodents from Inglis 1C, Citrus County, Florida", 2001 The Society of Vertebrate Paleontology. Stable isotopes suggest that Castoroides probably predominantly consumed submerged aquatic plants, rather than the woody diet of living beavers. There is no evidence that giant beavers constructed dams or lodges. The shape of the incisors of Castoroides would have made it much less effective in cutting down trees than living beavers. It was likely heavily dependent on wetland environments for both food and protection from predators. [23] Extinction [ edit ] Mounted skeletonFryxell, J. M.; Doucet, C. M. (1993). "Diet Choice and the Funcional Response of Beavers". Ecology. 74 (5): 1297–1306. doi: 10.7589/2014-05-120. PMID 25380356. S2CID 5364807.

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: Callahan, M. (April 2005). "Best Management Solutions for Beaver Problems" (PDF). Association of Massachusetts Wetland Scientists: 12–14. Archived (PDF) from the original on October 9, 2022. Several versions of an Anishinaabe story tell of "giant beavers" who "walked upright and stood as tall as the tallest man." [32] Many scholars believe that stories like these could be evidence of North American indigenous peoples encountering C. ohioensis or, at the very least, their fossils. [33] See also [ edit ]

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.