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Three distinct Canada jay (Perisoreus canadensis) morphotypes with easily recognizable plumage traits come into contact in western North America. Recent work demonstrated high genetic structure across the species' range; however, patterns of genetic variation in these contact zones remain unknown. We categorized 605 individuals into one of three morphotypes (Pacific, Rocky Mountain, and Boreal) based on plumage, and genotyped individuals at the mtDNA control region and 12 microsatellite loci to assess the extent of hybridization between morphotypes. Our data showed cryptic genetic diversity and high cytonuclear discordance among morphotypes within contact zones, which is likely the result of recent and historical admixture. The distributions of the Boreal and Pacific morphotypes each showed a strong association with a single, distinct genetic group, whereas the Rocky Mountain morphotype exhibited higher genetic diversity and was associated with multiple genotypes. Our analyses show the importance of considering both plumage and genetic traits when examining contact zones between closely related taxa. Finally the data presented in this study reaffirm that the Pacific morphotype is distinct from the Boreal and Rocky Mountain morphotypes based on genetic, phenotypic and ecological data, indicating that the Pacific morphotype should be re-elevated to a full species. [ABSTRACT FROM AUTHOR]

The American Ornithologists' Union's check-list of North American birds is presented including Puffinus subalaris Galapagos Shearwater, Accipiter soloensis Gray Frog-Hawk and Buteo nitidus Gray Hawk.

This article presents the 11th supplement of the seventh edition of the Checklist of North American Birds (American Ornithologists' Union ( AOU) 1998). Decisions made by the AOU's Committee on Classification and Nomenclature-North and Middle America between April 1, 2010 and April 15, 2011 are summarized in the supplement. It presents the changes in the supplement including six species which are added to the main list on the basis of new directional information.

The article presents a list of changes and updates regarding the classification of birds in North America by the American Ornithologists' Union (AOU). It states that such makes it the 51st supplement since the publication's first, and the 10th since its 7th one in the 1988 edition. The new list was reportedly created by the Committee on Classification and Nomenclature of the AOU, and made between January 1, 2009 to March 31, 2010. A technical description of new findings in genetic make-up and new animal discoveries follows, which rate the changes.

The article presents the Forty-Ninth Supplement to the Check-list of North American Birds by the American Ornithologists' Union (AOU). It states the changes in the supplement including the additions to the main list for distributional information, the addition of six genera, and the removal of the species Buteogallus subtilis. The article shows the summary of decisions made by the Committee on Classification and Nomenclature of the AOU in North and Middle America for the calendar year 2007.

Presents the 45th supplement to the American Ornithologists' Union "Check-List of North American Birds." Categories of the changes in the supplement; Species of birds added to the list; List of bird names in English that were changed without change in the scientific name.

Presents a listing of bird species found in North America provided by the American Ornithologists' Union.

Presents the 43rd supplement to the American Ornithologists' Union's (AOU) check-list of North American birds which is a summary of the decisions made by the Committee on Classification and Nomenclature of the AOU between January 1, 2000 and December 31, 2001.

Investigates the different species of the Least Tern in North America. Identification of the different species; Where do these species nest; Information on the category in which the subspecies should be assessed; Sex differences between the birds; Methodology used to carry out the investigation; Results of the investigation.

We describe range-wide phylogeographic variation in gray jays (Perisoreus canadensis), a boreal Nearctic corvid that occurs today primarily in recently glaciated regions. Phylogenetic analysis of mitochondrial DNA (1041 base pairs ND2 gene; N=205, 50 localities) revealed four reciprocally monophyletic groups. One widespread clade occurs across the North American boreal zone, from Newfoundland to Alaska and southwest into Utah. Three other clades occur at lower latitudes in the montane West in Colorado, the northern Rocky Mountains, and the Pacific Northwest respectively. The geographic distribution of clades in gray jays corresponds with a general pattern that is emerging for boreal taxa, having one widespread northern clade and one or more geographically restricted southwestern clades. Population genetic analyses indicate that the larger boreal clade is genetically structured and harbors significantly more genetic diversity than those clades occurring at lower latitudes. Species distribution modeling (SDM) revealed multiple putative Pleistocene refugia including several occurring at higher latitudes. We suggest that multiple post-glacial colonization routes, some of which originate from these northern refugia, are responsible for the relatively high genetic diversity at high latitudes. Conversely, lower latitude clades show little variation, probably as a result of historical restriction to smaller geographical areas with smaller long-term population sizes. This 'upside-down' pattern of genetic diversity contrasts with the conventional view that populations of north-temperate species occupying previously glaciated habitats should possess lower levels of diversity than their southern counterparts., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The timing of origin of modern North American bird species in relation to Pleistocene glaciations has long been the topic of significant discussion and disagreement. Recently, Klicka and Zink (1997) and Avise and Walker (1998) enlivened this debate by using calibrated molecular distance values to estimate timing of speciations. Here we use new molecular studies to test their conclusions. Molecular distance values for 39 pairs of proven sister species, 27 of which are based on new data, alter the currently perceived pattern that avian species splits occurred mainly in the Pliocene and early-mid-Pleistocene. Mitochondrial DNA divergence values for this set of taxa showed a skewed distribution pointing toward relatively young speciation times, in contrast to the pattern presented by Klicka and Zink (1997) for 35 sister plus non-sister species pairs. Our pattern was not significantly different from that of Avise and Walker (1998) for "intraspecific phylogroups," some of which are species. We conclude that the entire Pleistocene, including the last two glacial cycles (<250,000 years ago), was important in speciations of modern North American birds. A substantial number of speciations were both initiated and completed in the last 250,000 years. Simultaneously, many taxa began to diverge in the Pleistocene but their speciations are not yet complete (per Avise and Walker 1998). The suggestion that durations of speciations average two million years is probably a substantial overestimate.