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Full-Text Articles in Life Sciences
Genetic Admixture In Multidimensional Niche Space: Asymmetrical Niche Similarity Promotes Gene Flow In Armadillos (Dasypus Novemcinctus), Maria Arteaga, John Mccormack, Luis Eguiarte, Rodrigo Medellín
Genetic Admixture In Multidimensional Niche Space: Asymmetrical Niche Similarity Promotes Gene Flow In Armadillos (Dasypus Novemcinctus), Maria Arteaga, John Mccormack, Luis Eguiarte, Rodrigo Medellín
John E. McCormack
We unite genetic data with a robust test of niche divergence to test the hypothesis that patterns of gene flow between two lineages of the nine-banded armadillo are influenced by their climatic niches. We collected Geographical Information System (GIS) data on climate using locality information from 111 individuals from two lineages that had associated genetic material. We tested whether niches of these lineages were more conserved or divergent than the background environments of their geographic ranges and found evidence for niche conservatism on two axes and no evidence for divergence on any axis. To address the role of niche similarity …
New Phylogenetic Information Suggests Both An Increase And At Least One Loss Of Cooperative Breeding During The Evolutionary History Of Aphelocoma Jays, Elena Berg, Robert Aldredge, A. Peterson, John Mccormack
New Phylogenetic Information Suggests Both An Increase And At Least One Loss Of Cooperative Breeding During The Evolutionary History Of Aphelocoma Jays, Elena Berg, Robert Aldredge, A. Peterson, John Mccormack
John E. McCormack
Efforts to identify ecological and life history factors associated with cooperative breeding have been largely unsuccessful, and interest is growing in the role of phylogenetic history in determining the distribution of this social system among lineages. In birds, cooperative breeding is distributed non-randomly among lineages, suggesting that phylogenetic inertia may play an important role in determining its distribution. The bird genus Aphelocoma has been particularly well studied because, although it is a relatively small genus, it shows broad among-lineage variation in level of cooperation. Previous analyses described an unusual unidirectional pattern of evolutionary loss of cooperation in Aphelocoma. Here, historical …
Calibrating Divergence Times On Species Tree Versus Gene Trees: Implications For Speciation History Of Aphelocoma Jays, John Mccormack, Joseph Heled, Kathleen Delaney, A. Peterson, L. Knowles
Calibrating Divergence Times On Species Tree Versus Gene Trees: Implications For Speciation History Of Aphelocoma Jays, John Mccormack, Joseph Heled, Kathleen Delaney, A. Peterson, L. Knowles
John E. McCormack
Estimates of the timing of divergence are central to testing the underlying causes of speciation. Relaxed molecular clocks and fossil calibration have improved these estimates; however, these advances are implemented in the context of gene trees, which can overestimate divergence times. Here we couple recent innovations for dating speciation events with the analytical power of species trees, where multilocus data are considered in a coalescent context. Divergence times are estimated in the bird genus Aphelocoma to test whether speciation in these jays coincided with mountain uplift or glacial cycles. Gene trees and species trees show general agreement that diversification began …