Journal ArticleDOI
Genetic relationships of North American bears (Ursus) inferred from amplified fragment length polymorphisms and mitochondrial DNA sequences
Reads0
Chats0
TLDR
The data indicate that extant populations of brown bears and polar bears have separate nuclear and mitochondrial gene pools and are supported as species under the genetic species concept.Abstract:
The three species of bears in North America, polar bears (Ursus maritimus Phipps, 1774), brown bears (Ursus arctos L., 1758), and black bears (Ursus americanus Pallas, 1780), have differentiated morphologies and nuclear and mitochondrial genomes. An exception is a paraphyletic mitochondrial DNA relationship and some nuclear gene lineages common to polar bears and a population of brown bears from islands in southeast Alaska. In this study, we quantified the genetic relationships of extant brown bears and black bears from Alaska and Montana, and polar bears from Alaska, with amplified fragment length polymor- phisms (AFLP) and mtDNA cytochrome-b sequences. Bayesian cluster analyses of the AFLP data show each species is distinct. All brown bears, including those from the islands in southeast Alaska, cluster separately from polar bears, and black bears cluster separately from brown bears and polar bears. The mtDNA of polar bears and southeast Alaska island brown bears is paraphyletic as reported previously, but the species have different haplotypes. These data indicate that extant populations of brown bears and polar bears have separate nuclear and mitochondrial gene pools and are supported as species under the genetic species concept. Resume : Les trois especes d'ours d'Amerique du Nord, l'ours blanc (Ursus maritimus Phipps, 1774), le grizzli (Ursus arctos L., 1758) et l'ours noir (Ursus americanus Pallas, 1780), ont des morphologies et des genomes nucleaires et mitochondriaux differencies. Une relation paraphyletique de l'ADN mitochondrial et certaines lignees de genes nucleaires qu'ont en commun les ours blancs et une population de grizzlis des iles du sud-est de l'Alaska constituent toutefois des exceptions notables. Nous avons quantifie les relations genetiques entre des grizzlis et des ours noirs vivant aujourd'hui en l'Alaska et au Montana, et des ours blancs de l'Alaska ala lumiere de polymorphismes de longueur de fragments amplifies (AFLP) et de sequences du cytochrome-b de l'ADNmt. Des analyses bayesiennes de regroupement des donnees d'AFLP indiquent que chaque espece est distincte. Tous les grizzlis, y compris ceux des iles du sud-est de l'Alaska, forment un groupe distinct des ours blancs, et les ours noirs forment un groupe distinct des grizzlis et des ours blancs. L'ADNmt des ours blancs et des grizzlis des iles du sud-est de l'Alaska est paraphyletique, ce qui concorde avec les conclusions d'etudes anterieures, mais les deux especes ont des haplotypes distincts. Ces donnees indiquent que les populations actuelles de grizzlis et d'ours blancs presentent des patrimoines genetiques nucle- aires et mitochondriaux distincts et constituent des especes distinctes en vertu du concept des especes genetiques. (Traduit par la Redaction) Mots-cles : polymorphisme de longueur de fragments amplifies, ours, cytochrome b, ADN mitochondrial, Ursus americanus, Ursus arctos, Ursus maritimus.read more
Citations
More filters
Journal ArticleDOI
Bears in a Forest of Gene Trees: Phylogenetic Inference Is Complicated by Incomplete Lineage Sorting and Gene Flow
TL;DR: Gene flow detected from brown into American black bears can explain the conflicting placement of the American black bear in mitochondrial and nuclear phylogenies, and highlights that both incomplete lineage sorting and introgression are prominent evolutionary forces even on time scales up to several million years.
Book ChapterDOI
Detecting the Number of Clusters through Cluster Validation
Amparo Albalate,Wolfgang Minker +1 more
Journal ArticleDOI
Brown and Polar Bear Y Chromosomes Reveal Extensive Male-Biased Gene Flow within Brother Lineages
Tobias Bidon,Axel Janke,Steven R. Fain,Hans Geir Eiken,Snorre B. Hagen,Urmas Saarma,Björn M. Hallström,Nicolas Lecomte,Frank Hailer +8 more
TL;DR: Y chromosome evidence support the emerging understanding that brown and polar bears started to diverge no later than the Middle Pleistocene, and highlights the importance of analyzing both maternally and paternally inherited loci for a comprehensive view of phylogeographic history.
ARTICLE / DISCOVERIES SECTION Title: Brown and polar bear Y chromosomes reveal extensive male-biased gene flow within brother lineages
Tobias Bidon,Axel Janke,Steven R. Fain,Hans Geir,Snorre B. Hagen,Urmas Saarma,Björn M. Hallström,Nicolas Lecomte,Frank Hailer +8 more
Journal ArticleDOI
Recent Hybridization between a Polar Bear and Grizzly Bears in the Canadian Arctic
TL;DR: Grizzly bears have recently become more common on the Arctic Islands in the Inuvialuit Settlement Region, concurrently with a period of environmental change, triggering extensive discussion and speculation regarding the impact of hybridization on the parent species.
References
More filters
Journal ArticleDOI
MEGA5: Molecular Evolutionary Genetics Analysis using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods
Koichiro Tamura,Daniel S. Peterson,Nicholas Peterson,Glen Stecher,Masatoshi Nei,Sudhir Kumar +5 more
TL;DR: The newest addition in MEGA5 is a collection of maximum likelihood (ML) analyses for inferring evolutionary trees, selecting best-fit substitution models, inferring ancestral states and sequences, and estimating evolutionary rates site-by-site.
Journal ArticleDOI
Inference of population structure using multilocus genotype data
TL;DR: Pritch et al. as discussed by the authors proposed a model-based clustering method for using multilocus genotype data to infer population structure and assign individuals to populations, which can be applied to most of the commonly used genetic markers, provided that they are not closely linked.
Journal ArticleDOI
MrBayes 3: Bayesian phylogenetic inference under mixed models
TL;DR: MrBayes 3 performs Bayesian phylogenetic analysis combining information from different data partitions or subsets evolving under different stochastic evolutionary models to analyze heterogeneous data sets and explore a wide variety of structured models mixing partition-unique and shared parameters.
Journal ArticleDOI
Detecting the number of clusters of individuals using the software STRUCTURE: a simulation study.
TL;DR: It is found that in most cases the estimated ‘log probability of data’ does not provide a correct estimation of the number of clusters, K, and using an ad hoc statistic ΔK based on the rate of change in the log probability between successive K values, structure accurately detects the uppermost hierarchical level of structure for the scenarios the authors tested.
Journal ArticleDOI
genalex 6: genetic analysis in Excel. Population genetic software for teaching and research
Rodney Peakall,Peter E. Smouse +1 more
TL;DR: Genalex is a user-friendly cross-platform package that runs within Microsoft Excel, enabling population genetic analyses of codominant, haploid and binary data.
Related Papers (5)
Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change
Webb Miller,Stephan C. Schuster,Stephan C. Schuster,Andreanna J. Welch,Aakrosh Ratan,Oscar C. Bedoya-Reina,Fangqing Zhao,Fangqing Zhao,Hie Lim Kim,Richard Burhans,Daniela I. Drautz,Nicola E. Wittekindt,Lynn P. Tomsho,Enrique Ibarra-Laclette,Luis Herrera-Estrella,Elizabeth Peacock,Sean D. Farley,George K. Sage,Karyn D. Rode,Martyn E. Obbard,Rafael Montiel,Lutz Bachmann,Ólafur Ingólfsson,Ólafur Ingólfsson,Jon Aars,Thomas Mailund,Øystein Wiig,Sandra L. Talbot,Charlotte Lindqvist +28 more
Ancient Hybridization and an Irish Origin for the Modern Polar Bear Matriline
Ceiridwen J. Edwards,Marc A. Suchard,Philippe Lemey,John J. Welch,Ian Barnes,Tara L. Fulton,Ross Barnett,Tamsin C. O'Connell,Peter Coxon,Nigel T. Monaghan,Cristina Valdiosera,Eline D. Lorenzen,Eske Willerslev,Gennady F. Baryshnikov,Andrew Rambaut,Mark G. Thomas,Mark G. Thomas,Daniel G. Bradley,Beth Shapiro +18 more
Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary
Johannes Krause,Tina Unger,Nocon Aline,Anna-Sapfo Malaspinas,Sergios-Orestis Kolokotronis,Sergios-Orestis Kolokotronis,Mathias Stiller,Leopoldo Héctor Soibelzon,Helen Spriggs,Paul H. Dear,Adrian W. Briggs,Sarah C Bray,Stephen J. O'Brien,Gernot Rabeder,Paul Matheus,Alan Cooper,Montgomery Slatkin,Svante Pääbo,Michael Hofreiter +18 more