ALTSHULER, Douglas L.; DUDLEY, Robert; California Institute of Technology; University of California, Berkeley: The physiology and biomechanics of bird flight across elevations. Many birds fly at high altitude, either during long-distance flights or by virtue of residence in high elevation habitats. Among the many environmental features that vary with altitude, five may have significant consequences […]

EDWARDS, J.S.; univ of Washinton: Sustenance of arthropod populations at high altitude The high alpine habitat occupies a small fraction of Earth’s total land area. About 20% lies above 1 kilometer, and relatively little of this entails steep altitudinal gradients that bring lowland and alpine environments into proximity. On a broad scale the habitat is […]

DILLON, M.E.*; FRAZIER, M.R.; DUDLEY, R.; Univ. of Washington; Univ. of Washington; Univ. of California, Berkeley: Physiological and biomechanical performance of arthropods at high altitude A variety of physical parameters that impinge on arthropod physiology exhibit substantial variation with altitude, including temperature, air density, and oxygen partial pressure. Changes in these parameters relative to sea-level […]

EVANS-OGDEN, L.J.; MARTIN, K.; University of British Columbia; University of British Columbia: Impacts of Elevation on Life History High elevation habitats are ecologically challenging environments, and relatively few species have evolved life histories specifically adapted to such habitats. Ecological conditions at high elevations, such as extremes in climate, protracted breeding seasons, and fluctuations in food […]

FJELDS�, J.; RAHBEK, C.; Zoological Museum, University of Copenhagen; Zoological Museum, University of Copenhagen: Diversification of a speciose Neotropical bird group from lowlands to highlands The process of diversification since the upper Tertiary was studied by linking together well-resolved phylogenies and species distributions for tanagers (Aves, Thraupini). Most species representing early phylogenetic branching are broadly […]

MONSON, R.K.*; LIPSON, D.A.; ROSENSTIEL, T.N.; FORBIS, T.A.; Univ. of Colorado, Boulder; San Diego State Univ.; Univ. of Colorado, Boulder; Univ. of Colorado, Boulder: Carbon and Nitrogen Storage by Alpine Herbs Alpine plants have limited seasonal access to the resources they require for growth and persistence. Resource storage is commonly observed as a means to […]

XAVIER-NETO, Jose*; SIM�ES-COSTA, Marcos S; Instituto do Coracao HC FMUSP; Instituto do Coracao HC FMUSP: The evolutionary origins of cardiac chambers We suggest cardiac chambers evolved from anterior-posterior patterning of invertebrate peristaltic pumps, which lack efficient coordination between inflow/outflow. Strong evidence implicates retinoic acid (RA) signaling in this process. In amniotes, a caudorostral wave of […]

HEASMAN , Janet *; TAO, Qinghua ; YOKOTA, Chika ; KOFRON , Matt; LIN, Xinhua ; 1Division of Developmental Biology, Cincinnati Children�s Research Foundation: The canonical Wnt pathway and axis formation in Xenopus laevis The establishment of the dorso-ventral and anterior posterior axes in Xenopus embryos has long been known to depend on a canonical […]

DUBOC, V.*; R�TTINGER, E.; LAPRAZ, F.; BESNARDEAU, L.; LEPAGE, T.; UMR 7009 CNRS-UPMC : Role of Nodal in establishment of sea urchin larva body plan Nodal factors play crucial roles during embryogenesis of chordates. They have been implicated in a number of developmental processes, including mesoderm and endoderm formation and patterning of the embryo along […]

SHOOK, David*; KELLER, Ray; Univ. of Virginia, Charottesville: Evolution of Vertebrate Mesoderm Morphogenesis The Chordate lineage shows a evolutionary trend from mesoderm internalization by budding off epithelial tubes, as in ascidians and amphioxus, to internalization by ingression, as in the amniotes. Urodele amphibians appear to be an interesting intermediate in this transition, using an epithelial […]