The Council of the American Genetic Association has reached a decision regarding the Journal of Heredity Outstanding Student-Authored Paper Award (formerly the Stephen J. O'Brien Award) for manuscripts published during 2021. This year, eleven articles in Volume 112 that were first-authored by a student were considered, and the award presented to Sheela Turbek for her paper, Variable Signatures of Selection Despite Conserved Recombination Landscapes Early in Speciation (Sheela P Turbek, Georgy A Semenov, Erik D Enbody, Leonardo Campagna, Scott A Taylor). JHered 2021. 111-6, pp 485–496.
The evaluation committee had the following comments on this top-ranked article:
“Rarely do studies focus on the confounding role that variable recombination rates across the genome might play in shaping patterns of genomic differentiation. This reads like a tour de force describing the factors linking recombination and landscapes of genomic differentiation.”
Sheela will receive a $2,000 prize, a certificate, and up to $1,500 toward expenses to attend and present a talk at the 2022 AGA President’s Symposium.
Study Summary and Importance:
Genetic recombination plays an essential role in evolution by generating new nucleotide
combinations upon which natural selection can act. A growing body of literature indicates that
recombination rate can vary widely across the genome, and that this variation in turn influences
estimates of genomic differentiation (e.g., FST) often used to identify loci under divergent
selection. However, our understanding of the association between patterns of recombination and
landscapes of genomic differentiation during the earliest stages of the speciation process remains
This study took advantage of population genomic data from two avian radiations (southern
capuchino seedeaters and white wagtails), which have rapidly diversified in mate preferences
and genes encoding plumage coloration, to investigate the location of divergence peaks involved
in species differences in relation to fine-scale patterns of recombination. The study found that the
few narrow regions of elevated genomic divergence that differentiate closely related lineages
tend to fall in genomic regions of relatively low recombination. These results suggest that the
location of divergence peaks underlying plumage differences in areas of low recombination may
have protected these regions from the effects of gene flow, allowing diversification to proceed in
these rapid radiations. In addition, the study highlights the importance of considering the
confounding effect of variation in recombination rate when interpreting patterns of elevated
genomic differentiation early in the speciation process.
Sheela Turbek is a postdoctoral researcher with Dr. Kristen Ruegg at Colorado State University.
In 2021, she obtained her PhD in Ecology and Evolutionary Biology from the University of
Colorado Boulder, where she studied the mechanisms that generate and maintain biodiversity.