Dataset Information

Genetic architecture and evolution of color variation in American black bears.

ABSTRACT: Color variation is a frequent evolutionary substrate for camouflage in small mammals, but the underlying genetics and evolutionary forces that drive color variation in natural populations of large mammals are mostly unexplained. The American black bear, Ursus americanus (U. americanus), exhibits a range of colors including the cinnamon morph, which has a similar color to the brown bear, U. arctos, and is found at high frequency in the American southwest. Reflectance and chemical melanin measurements showed little distinction between U. arctos and cinnamon U. americanus individuals. We used a genome-wide association for hair color as a quantitative trait in 151 U. americanus individuals and identified a single major locus (p < 10^-13). Additional genomic and functional studies identified a missense alteration (R153C) in Tyrosinase-related protein 1 (TYRP1) that likely affects binding of the zinc cofactor, impairs protein localization, and results in decreased pigment production. Population genetic analyses and demographic modeling indicated that the R153C variant arose 9.36 kya in a southwestern population where it likely provided a selective advantage, spreading both northwards and eastwards by gene flow. A different TYRP1 allele, R114C, contributes to the characteristic brown color of U. arctos but is not fixed across the range.

SUBMITTER: Puckett EE

PROVIDER: S-EPMC10039708 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Genetic architecture and evolution of color variation in American black bears.

Puckett Emily E EE Davis Isis S IS Harper Dawn C DC Wakamatsu Kazumasa K Battu Gopal G Belant Jerrold L JL Beyer Dean E DE Carpenter Colin C Crupi Anthony P AP Davidson Maria M DePerno Christopher S CS Forman Nicholas N Fowler Nicholas L NL Garshelis David L DL Gould Nicholas N Gunther Kerry K Haroldson Mark M Ito Shosuke S Kocka David D Lackey Carl C Leahy Ryan R Lee-Roney Caitlin C Lewis Tania T Lutto Ashley A McGowan Kelly K Olfenbuttel Colleen C Orlando Mike M Platt Alexander A Pollard Matthew D MD Ramaker Megan M Reich Heather H Sajecki Jaime L JL Sell Stephanie K SK Strules Jennifer J Thompson Seth S van Manen Frank F Whitman Craig C Williamson Ryan R Winslow Frederic F Kaelin Christopher B CB Marks Michael S MS Barsh Gregory S GS

Current biology : CB 20221216 1

Color variation is a frequent evolutionary substrate for camouflage in small mammals, but the underlying genetics and evolutionary forces that drive color variation in natural populations of large mammals are mostly unexplained. The American black bear, Ursus americanus (U. americanus), exhibits a range of colors including the cinnamon morph, which has a similar color to the brown bear, U. arctos, and is found at high frequency in the American southwest. Reflectance and chemical melanin measurem ...[more]

PMID: 36528024

Similar Datasets

Project description:American black bears (Ursus americanus) are seasonally polyoestrous and exhibit delayed implantation, which may allow equal and independent fertility of recurrent oestruses of a mating season. We postulated that the luteal inactivity during delayed implantation allows bears to have sequential ovulation during a polyoestrous mating season such that each oestrus of a polyoestrous female will have equivalent fertility, and pregnancy would not preclude subsequent ovulation and superfetation. Controlled mating experiments were conducted on semi-free-ranging female American black bears during three mating seasons, wherein females were bred by different male cohorts in each oestrus. Behavioural observation, vulva score ranking, genetic paternity analysis, gross morphology of ovaries and microscopic morphology of diapaused embryos were used to evaluate the fertility of each subsequent oestrus in polyoestrous females. Oestrus duration, number of successful mounts and median vulva scores were similar between first and subsequent oestruses of the season. Polyoestrus occurred in 81.3% of oestrous females, with a 9.7 ± 5.5 day (mean ± SD) inter-oestrous interval. Sequential ovulation was documented in three polyoestrous females, including one that possessed both a corpus haemorrhagicum and a developed corpus luteum. Among polyoestrous dams, four of nine embryos were conceived in the first oestrus and five of nine in the second oestrus. These results indicate that each oestrus of polyoestrous females is capable of fertility, even if the female is already pregnant from a prior oestrus. Although superfetation was not directly observed in the present study, our results strongly suggest the potential of superfetation in the American black bear and provide novel insight into the complex behavioural and physiological breeding mechanisms of bears. Given that most endangered bear species share similar reproductive traits with American black bears, captive breeding programmes could take advantage of superfetation by mating females with different males at each subsequent oestrus of the season in order to increase the genetic diversity of captive endangered bears.

Dataset Information

Genetic architecture and evolution of color variation in American black bears.

Publications

Genetic architecture and evolution of color variation in American black bears.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets