Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Language
Year
  • 1
    Language: English
    In: Science, 2012, Vol.336(6079), pp.344-347
    Description: Recent studies have shown that the polar bear matriline (mitochondrial DNA) evolved from a brown bear lineage since the late Pleistocene, potentially indicating rapid speciation and adaption to arctic conditions. Here, we present a high-resolution data set from multiple independent loci across the nuclear...
    Keywords: Medicin Och Hälsovetenskap ; Klinisk Medicin ; Neurologi ; Medical And Health Sciences ; Clinical Medicine ; Neurology ; Medicin Och Hälsovetenskap ; Klinisk Medicin ; Kirurgi ; Medical And Health Sciences ; Clinical Medicine ; Surgery
    ISSN: 1095-9203
    ISSN: 00368075
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    In: Molecular Ecology, March 2015, Vol.24(6), pp.1161-1163
    Description: The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of , Cahill . (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof () Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male‐biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the Island population in which an Alaskan brown bear served as a putatively admixture‐free reference, Cahill . (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach.
    Keywords: Admixture ; Evolutionary Genetics ; Genomics ; Introgression ; Landscape Genetics ; Mammals ; Phylogeography ; U Rsus
    ISSN: 0962-1083
    E-ISSN: 1365-294X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Journal of Mammalogy, 1 October 2011, Vol.92(5), pp.1070-1080
    Description: Ecological invasions of generalist species often are facilitated by anthropogenic disturbance. Coyotes (Canis latrans) have benefitted from anthropogenic changes to North American ecosystems and have experienced a dramatic range expansion since the early 19th century. The region east of the Mississippi River has been colonized via 2 routes that have converged in the mid-Atlantic region during the past few decades. Coyotes using the northern route of expansion show molecular evidence of admixture with the Great Lakes wolf (GLW). We used noninvasive molecular techniques to detect the geographic origins of the recent coyote colonization of northern Virginia as a representative of the mid-Atlantic region and to detect signatures of admixture with GLWs. Of 455 individual canid scats screened, we sequenced a variable 282-base pair fragment of the mitochondrial control region from 126 coyote scats, assigned individual identities to samples using 6 microsatellite loci, and conducted phylogeographic analyses by comparing our sequences to previously published haplotypes. In 39 individuals identified in our scat surveys we detected 7 mitochondrial DNA haplotypes, all of which have been previously reported in diverse surrounding geographic localities. Phylogeographic analyses indicate multiple sources of colonization of northern Virginia. One common haplotype detected in northern Virginia is of wolf origin, indicating the presence of admixed coyotes and GLWs from the north.
    Keywords: Biological sciences -- Biology -- Genetics ; Biological sciences -- Biology -- Zoology ; Physical sciences -- Earth sciences -- Geography ; Biological sciences -- Ecology -- Ecological zones ; Physical sciences -- Chemistry -- Chemical compounds ; Biological sciences -- Biology -- Conservation biology ; Biological sciences -- Biology -- Conservation biology ; Biological sciences -- Biology -- Genetics ; Biological sciences -- Ecology -- Population ecology ; Physical sciences -- Chemistry -- Chemical compounds
    ISSN: 00222372
    E-ISSN: 15451542
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Molecular Phylogenetics and Evolution, February 2015, Vol.83, pp.40-43
    Description: Eagles currently occur in the Hawaiian Islands only as vagrants, but Quaternary bones of eagles have been found on three of the major islands. A previous study of a ∼3500-year-old skeleton from Maui found its mtDNA more similar to White-tailed ( ) than to Bald ( ) Eagles, but low intraspecific resolution of the markers and lack of comparative data from mainland populations precluded assessment of whether the individual was part of the diversity found in Eurasia, or whether it represented an endemic Hawaiian lineage. Using ancient DNA techniques, we sequenced part of the rapidly evolving mtDNA control region from the same specimen, and compared it to published range-wide control region data from White-tailed Eagles and newly generated sequences from Bald Eagles. Phylogenetic analyses indicated that the Hawaiian eagle represents a distinct (〉3% divergent) mtDNA lineage most closely related to those of extant White-tailed Eagles. Based on fossil calibration, we estimate that the Hawaiian mtDNA lineage diverged from mainland sequences around the Middle Pleistocene. Although not clearly differentiated morphologically from mainland forms, the Hawaiian eagle thus likely constituted an isolated, resident population in the Hawaiian archipelago for more than 100,000 years, where it was the largest terrestrial predator.
    Keywords: Ancient DNA ; Bald Eagle ; Island Endemic ; Haliaeetus Albicilla ; Haliaeetus Leucocephalus ; Mtdna ; Biology
    ISSN: 1055-7903
    E-ISSN: 1095-9513
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: PLoS ONE, 01 January 2013, Vol.8(9), p.e71668
    Description: The critically endangered Central American River Turtle (Dermatemys mawii) is the only remaining member of the Dermatemydidae family, yet little is known about its population structuring. In a previous study of mitochondrial (mt) DNA in the...
    Keywords: Sciences (General)
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    In: Proceedings of the Royal Society B, 2011, Vol.278(1707), pp.817-825
    Description: The Galapagos Islands are renowned for their high degree of endemism. Marine taxa inhabiting the archipelago might be expected to be an exception, because of their utilization of pelagic habitats—the dispersal barrier for terrestrial taxa—as foraging grounds. Magnificent frigatebirds ( Fregata magnificens ) have a highly vagile lifestyle and wide geographical distribution around the South and Central American coasts. Given the potentially high levels of gene flow among populations, the species provides a good test of the effectiveness of the Galapagos ecosystem in isolating populations of highly dispersive marine species. We studied patterns of genetic (mitochondrial DNA, microsatellites and nuclear introns) and morphological variation across the distribution of magnificent frigatebirds. Concordant with predictions from life-history traits, we found signatures of extensive gene flow over most of the range, even across the Isthmus of Panama, which is a major barrier to gene flow in other tropical seabirds. In contrast, individuals from the Galapagos were strongly differentiated from all conspecifics, and have probably been isolated for several hundred thousand years. Our finding is a powerful testimony to the evolutionary uniqueness of the taxa inhabiting the Galapagos archipelago and its associated marine ecosystems.
    Keywords: Research articles
    ISSN: 0962-8452
    E-ISSN: 1471-2945
    E-ISSN: 14712954
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    In: Molecular Ecology, December 2015, Vol.24(24), pp.6041-6060
    Description: High‐resolution, male‐inherited Y‐chromosomal markers are a useful tool for population genetic analyses of wildlife species, but to date have only been applied in this context to relatively few species besides humans. Using nine Y‐chromosomal and three Y‐chromosomal single nucleotide polymorphism markers (Y‐s), we studied whether male gene flow was important for the recent recovery of the brown bear () in Northern Europe, where the species declined dramatically in numbers and geographical distribution during the last centuries but is expanding now. We found 36 haplotypes in 443 male extant brown bears from Sweden, Norway, Finland and northwestern Russia. In 14 individuals from southern Norway from 1780 to 1920, we found two Y chromosome haplotypes present in the extant population as well as four Y chromosome haplotypes not present among the modern samples. Our results suggested major differences in genetic connectivity, diversity and structure between the eastern and the western populations in Northern Europe. In the west, our results indicated that the recovered population originated from only four male lineages, displaying pronounced spatial structuring suggestive of large‐scale population size increase under limited male gene flow within the western subpopulation. In the east, we found a contrasting pattern, with high haplotype diversity and admixture. This first population genetic analysis of male brown bears shows conclusively that male gene flow was not the main force of population recovery.
    Keywords: Gene Flow ; Haplogroups ; Haplotypes ; Male Dispersal ; Y‐ Snp ; Y‐ Str
    ISSN: 0962-1083
    E-ISSN: 1365-294X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: Zoological science, August 2013, Vol.30(8), pp.642-50
    Description: The terrestrial mammalian fauna of the North Japanese island, Hokkaido, is more similar to that of Southern Siberia than to the main island of Japan, Honshu. Three species of the genus Myodes (Muridae, Rodentia) are found on Hokkaido, but not on Honshu. While Myodes rufocanus and M. rutilus are widely distributed across Hokkaido as well as the Eurasian continent, M. rex, which is endemic to Hokkaido and its adjacent islands, shows a discontinuous distribution pattern. We analyzed the phylogeographic history of M. rex using the mitochondrial DNA control region in order to interpret their discontinuous distribution pattern. Phylogenetic relationships among 54 distinct haplotypes showed that M. rex can be divided into four clades that occur on the northern, central, and southern regions of the Hokkaido mainland and on Rishiri Island, respectively. The phylogroups in the northern and central regions were largely separated in space, although several areas of sympatry were found. The phylogroup in the southern region, which was clearly separated from other phylogroups, showed markedly low genetic variability. All analyzed individuals from the population on Rishiri belonged to a separate lineage. Across a range of divergence rate estimates, we dated the basal divergence of all phylogroups to the mid to late Pleistocene, with subsequent signals of population expansion within lineages. We conclude that current phylogeographic structure in M. rex likely reflects Pleistocene survival in several separate refugia in situ. Past glacial ages have thus played an important role in shaping the current distribution patterns of mammalian species on Hokkaido.
    Keywords: Arvicolinae -- Genetics
    ISSN: 0289-0003
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    In: Molecular Ecology Resources, September 2011, Vol.11(5), pp.831-834
    Description: We report the development of a reliable and efficient method for molecular sexing of all extant elephant taxa. We developed primers that amplify two short Y‐specific fragments ( and ) and one longer X‐specific fragment (), developed from elephant sequences in one multiplex PCR. All fragments were designed to be short (〈200 basepairs) for use with degraded DNA and to be 50 basepairs apart to optimize visualization on agarose gels or as electropherograms. The multiplex PCR method matched sexes for at least 97.9% of the noninvasive savannah elephant samples and produced the expected female/male banding patterns for 14 African forest and 11 Asian elephant samples. We found this method to be more robust, efficient and less prone to contamination than previously developed sexing methods for elephants.
    Keywords: Elephas Maximus ; Loxodonta A. Africana ; Loxodonta A. Cyclotis ; Molecular Sexing ; Noninvasive
    ISSN: 1755-098X
    E-ISSN: 1755-0998
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: PLoS ONE, 2008, Vol.3(10), p.e3333
    Description: Population densities of many species throughout the world are changing due to direct persecution as well as anthropogenic habitat modification. These changes may induce or increase the frequency of hybridization among taxa. If extensive, hybridization can threaten the genetic integrity or survival of endangered species. Three native species of the genus Canis , coyote ( C. latrans ), Mexican wolf ( C. lupus baileyi ) and red wolf ( C. rufus ), were historically sympatric in Texas, United States. Human impacts caused the latter two to go extinct in the wild, although they survived in captive breeding programs. Morphological data demonstrate historic reproductive isolation between all three taxa. While the red wolf population was impacted by introgressive hybridization with coyotes as it went extinct in the wild, the impact of hybridization on the Texas populations of the other species is not clear. ; We surveyed variation at maternally and paternally inherited genetic markers (mitochondrial control region sequence and Y chromosome microsatellites) in coyotes from Texas, Mexican wolves and red wolves from the captive breeding programs, and a reference population of coyotes from outside the historic red wolf range. Levels of variation and phylogenetic analyses suggest that hybridization has occasionally taken place between all three species, but that the impact on the coyote population is very small. ; Our results demonstrate that the factors driving introgressive hybridization in sympatric Texan are multiple and complex. Hybridization is not solely determined by body size or sex, and density-dependent effects do not fully explain the observed pattern either. No evidence of hybridization was identified in the Mexican wolf captive breeding program, but introgression appears to have had a greater impact on the captive red wolves.
    Keywords: Research Article ; Ecology -- Community Ecology And Biodiversity ; Ecology -- Conservation And Restoration Ecology ; Ecology -- Evolutionary Ecology ; Ecology -- Global Change Ecology ; Ecology -- Spatial And Landscape Ecology ; Evolutionary Biology -- Evolutionary Ecology ; Genetics And Genomics -- Population Genetics
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages