Aphelocoma jays (1 Viewer)

Island Scrub Jay

Langin, Sillett, Funk, Morrison, Desrosiers & Ghalambor (in press). Islands within an island: Repeated adaptive divergence in a single population. Evolution. [abstract]

Funk Lab, 3 Dec 2014: New paper by Dr. Katie Langin and colleagues on adaptive divergence in a single population of Island Scrub-Jays.

Eugenia Zarza, Brant C. Faircloth, Whitney L.E. Tsai, Robert W. Bryson Jr, John Klicka, John E. McCormack. Hidden histories of gene flow in highland birds revealed with genomic markers. Molecular Ecology, Accepted manuscript online: 20 August 2016.

[abstract]

Aphelocoma unicolor

Madhvi X Venkatraman, Devon A Deraad, Whitney L E Tsai, Eugenia Zarza, Amanda J Zellmer, James M Maley, John E Mccormack; Cloudy with a chance of speciation: integrative taxonomy reveals extraordinary divergence within a Mesoamerican cloud forest bird, Biological Journal of the Linnean Society, , bly156, https://doi.org/10.1093/biolinnean/bly156

Abstract:

The highlands of Mesoamerica harbour some of the highest biodiversity in the world, especially in cloud forests, but the landscape drivers of this diversification are not well known. Taxonomy in this region has been challenging owing to a lack of consensus about how to test species limits. We apply integrative taxonomy to an emblematic species of the Mesoamerican cloud forests, the unicolored jay (Aphelocoma unicolor). We assess divergence along three complementary axes (genetics, phenotype and ecological niche), finding evidence for differentiation among five lineages, currently described as subspecies, in isolated forest patches. DNA suggests that these lineages have long histories of divergence. Multivariate analysis of phenotype, along with an objective method for detecting phenotypic clusters, suggest that at least four of the five lineages are diagnosable. There was also a pattern of increasing ecological divergence through time. The divergence observed among lineages is comparable to other species-level divergences in the genus, arguing for elevation of at least two, and as many as four, lineages within A. unicolor to species rank. According to our time tree, cloud forest patches became isolated starting in the Pliocene and continuing into the Pleistocene, suggesting glacial cycles as the main drivers of speciation.

Aphelocoma unicolor dismantled. Some suggested English names:
Aphelocoma unicolor (Du Bus de Ghisignies, 1847). Unicolored Jay
Aphelocoma concolor (Cassin, 1848). Concolour Jay
Aphelocoma guerrerensis Nelson, 1903. Guerrero Jay
Aphelocoma oaxacae Pitelka, 1946. Oaxaca Jay.
Aphelocoma griscomi van Rossem, 1928. Griscom's Jay.

DeRaad, D.A., J.E. McCormack, N. Chen, A.T. Peterson, and R.G. Moyle (2022)
Combining species delimitation, species trees, and tests for gene flow clarifies complex speciation in scrub-jays
Systematic Biology (advance online publication)
doi: 10.1093/sysbio/syac034

Complex speciation, involving rapid divergence and multiple bouts of post-divergence gene flow, can obfuscate phylogenetic relationships and species limits. In North America, cases of complex speciation are common, due at least in part to the cyclical Pleistocene glacial history of the continent. Scrub-jays in the genus Aphelocoma provide a useful case study in complex speciation because their range throughout North America is structured by phylogeographic barriers with multiple cases of secondary contact between divergent lineages. Here, we show that a comprehensive approach to genomic reconstruction of evolutionary history, i.e., synthesizing results from species delimitation, species tree reconstruction, demographic model testing, and tests for gene flow, is capable of clarifying evolutionary history despite complex speciation. We find concordant evidence across all statistical approaches for the distinctiveness of an endemic southern Mexico lineage (A. w. sumichrasti), culminating in support for the species status of this lineage under any commonly applied species concept. We also find novel genomic evidence for the species status of a Texas endemic lineage A. w. texana, for which equivocal species delimitation results were clarified by demographic modeling and spatially explicit models of gene flow. Finally, we find that complex signatures of both ancient and modern gene flow between the non-sister California Scrub-Jay (A. californica) and Woodhouse’s Scrub-Jay (A. woodhouseii), result in discordant gene trees throughout the species’ genomes despite clear support for their overall isolation and species status. In sum, we find that a multi-faceted approach to genomic analysis can increase our understanding of complex speciation histories, even in well-studied groups. Given the emerging recognition that complex speciation is relatively commonplace, the comprehensive framework that we demonstrate for interrogation of species limits and evolutionary history using genomic data can provide a necessary roadmap for disentangling the impacts of gene flow and incomplete lineage sorting to better understand the systematics of other groups with similarly complex evolutionary histories.

Very nice to finally see sumichrasti properly addressed, and an interesting result with texana, I'll be keen to read the paper but haven't readily found it yet.