Genetic variation in haemoglobin is associated with evolved changes in breathing in high-altitude deer mice.

Physiological systems often have emergent properties but the effects of genetic variation on physiology are often unknown, which presents a major challenge to understanding the mechanisms of phenotypic evolution. We investigated whether genetic variants in haemoglobin (Hb) that contribute to high-altitude adaptation in deer mice (Peromyscus maniculatus) are associated with evolved changes in the control of breathing. We created F2 inter-population hybrids of highland and lowland deer mice to test for phenotypic associations of α- and β-globin variants on a mixed genetic background.

The adaptive benefit of evolved increases in hemoglobin-O affinity is contingent on tissue O diffusing capacity in high-altitude deer mice.

Background: Complex organismal traits are often the result of multiple interacting genes and sub-organismal phenotypes, but how these interactions shape the evolutionary trajectories of adaptive traits is poorly understood. We examined how functional interactions between cardiorespiratory traits contribute to adaptive increases in the capacity for aerobic thermogenesis (maximal O consumption, V̇Omax, during acute cold exposure) in high-altitude deer mice (Peromyscus maniculatus). We crossed highland and lowland deer mice to produce F inter-population hybrids, which expressed genetically based variation in hemoglobin (Hb) O affinity on a mixed genetic background.

A test of altitude-related variation in aerobic metabolism of Andean birds.

Endotherms at high altitude face the combined challenges of cold and hypoxia. Cold increases thermoregulatory costs, and hypoxia may limit both thermogenesis and aerobic exercise capacity. Consequently, in comparisons between closely related highland and lowland taxa, we might expect to observe consistent differences in basal metabolic rate (BMR), maximal metabolic rate (MMR) and aerobic scope.

An extinct hummingbird species that never was: a cautionary tale about sampling issues in molecular phylogenetics.

The selection of species and individuals for molecular analyses critically affects inferences in various fields of systematic biology including phylogenetics, phylogeography, and species delimitation. Especially in areas like the Neotropical region where molecular analyses have recovered substantial within-species divergence and unexpected affinities of populations (Turchetto-Zolet et al. 2013), biases resulting from incomplete taxonomic or geographic sampling may compromise the understanding of phylogenetic relationships (Avendaño et al.

No population genetic structure in a widespread aquatic songbird from the Neotropics.

Neotropical lowland organisms often show marked population genetic structure, suggesting restricted migration among populations. However, most phylogeographic studies have focused on species inhabiting humid forest interior. Little attention has been devoted to the study of species with ecologies conducive to dispersal, such as those of more open and variable environments associated with watercourses.