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Full-Text Articles in Life Sciences

Mexican Jay (Aphelocoma Ultramarina), John Mccormack, L. Brown Sep 2008

Mexican Jay (Aphelocoma Ultramarina), John Mccormack, L. Brown

John E. McCormack

No abstract provided.


Niche Expansion Leads To Small-Scale Adaptive Divergence Along An Elevation Gradient In A Medium-Sized Passerine Bird, John Mccormack, Thomas Smith Aug 2008

Niche Expansion Leads To Small-Scale Adaptive Divergence Along An Elevation Gradient In A Medium-Sized Passerine Bird, John Mccormack, Thomas Smith

John E. McCormack

Niche expansion can lead to adaptive differentiation and speciation, but there are few examples from contemporary niche expansions about how this process is initiated. We assess the consequences of a niche expansion by Mexican jays (Aphelocoma ultramarina) along an elevation gradient. We predicted that jays at high elevation would have straighter bills adapted to feeding on pine cones, whereas jays at low elevation would have hooked bills adapted to feeding on acorns. We measured morphological and genetic variation of 95 adult jays and found significant differences in hook length between elevations in accordance with predictions, a pattern corroborated by analysis …


Assessing Osteoporosis Learning Needs And Preferences Of Exercise Physiologists, P D. Sollis, C J. Cisar Jun 2008

Assessing Osteoporosis Learning Needs And Preferences Of Exercise Physiologists, P D. Sollis, C J. Cisar

Craig J. Cisar

Research has revealed substantial knowledge deficits regarding osteoporosis among various healthcare professionals, such as physicians, nurses, and physical therapists. However, no previous studies have addressed the levels of knowledge regarding osteoporosis among exercise physiologists working in a cardiopulmonary rehabilitation setting. It is essential that exercise physiologists have a thorough understanding of osteoporosis so they can ensure client safety and provide accurate information to the client and support group. The purpose of this project was to evaluate the levels of knowledge about osteoporosis among exercise physiologists working with clients who are at high risk for fragility fractures. Ninety-six exercise physiologists (female …


Integrating Paleoecology And Genetics Of Bird Populations In Two Sky Island Archipelagos, John Mccormack, Bonnie Bowen, Thomas Smith May 2008

Integrating Paleoecology And Genetics Of Bird Populations In Two Sky Island Archipelagos, John Mccormack, Bonnie Bowen, Thomas Smith

John E. McCormack

Background: Genetic tests of paleoecological hypotheses have been rare, partly because recent genetic divergence is difficult to detect and time. According to fossil plant data, continuous woodland in the southwestern USA and northern Mexico became fragmented during the last 10,000 years, as warming caused cool-adapted species to retreat to high elevations. Most genetic studies of resulting 'sky islands' have either failed to detect recent divergence or have found discordant evidence for ancient divergence. We test this paleoecological hypothesis for the region with intraspecific mitochondrial DNA and microsatellite data from sky-island populations of a sedentary bird, the Mexican jay (Aphelocoma ultramarina). …


Speciation In The Highlands Of Mexico: Genetic And Phenotypic Divergence In The Mexican Jay (Aphelocoma Ultramarina), John Mccormack, A. Peterson, E. Bonaccorso, Thomas Smith Apr 2008

Speciation In The Highlands Of Mexico: Genetic And Phenotypic Divergence In The Mexican Jay (Aphelocoma Ultramarina), John Mccormack, A. Peterson, E. Bonaccorso, Thomas Smith

John E. McCormack

The pine-oak woodlands of the Mexican highlands harbour significant biological diversity, yet little is known about the evolutionary history of organisms inhabiting this region. We assessed genetic and phenotypic differentiation in 482 individuals representing 27 populations of the Mexican jay (Aphelocoma ultramarina) — a widespread bird species of the Mexican highlands — to test whether populations in the central and northern Mexican sierras display discrete breaks between groups, which would be consistent with a role for the different mountain chains in divergence and speciation. We found abrupt breaks in mitochondrial DNA (mtDNA; ND2 and control region) delineating four major genetic …


Perspectives In Ornithology: Application Of Tracking And Data-Logging Technology In Research And Conservation Of Seabirds, A E. Burger, Scott A. Shaffer Jan 2008

Perspectives In Ornithology: Application Of Tracking And Data-Logging Technology In Research And Conservation Of Seabirds, A E. Burger, Scott A. Shaffer

Scott A. Shaffer

No abstract provided.


Wind, Waves, And Wing Loading: Their Relative Importance To The At-Sea Distribution And Movements Of North And Central Pacific Albatrosses, R M. Suryan, D J. Anderson, Scott A. Shaffer, D D. Roby, Y Tremblay, D P. Costa, F Sato, K Ozaki, G Balogh Jan 2008

Wind, Waves, And Wing Loading: Their Relative Importance To The At-Sea Distribution And Movements Of North And Central Pacific Albatrosses, R M. Suryan, D J. Anderson, Scott A. Shaffer, D D. Roby, Y Tremblay, D P. Costa, F Sato, K Ozaki, G Balogh

Scott A. Shaffer

Among the varied adaptations for avian flight, the morphological traits allowing large-bodied albatrosses to capitalize on wind and wave energy for efficient long-distance flight are unparalleled. Consequently, the biogeographic distribution of most albatrosses is limited to the windiest oceanic regions on earth; however, exceptions exist. Species breeding in the North and Central Pacific Ocean (Phoebastria spp.) inhabit regions of lower wind speed and wave height than southern hemisphere genera, and have large intrageneric variation in body size and aerodynamic performance. Here, we test the hypothesis that regional wind and wave regimes explain observed differences in Phoebastria albatross morphology and we …