In a new ‘From the Cover’ paper out in Molecular Ecology (led by Doro Lindtke), we show that color and color pattern in Timema cristinate map to a single region of reduced recombination (likely an inversion) and that overdominance (i.e., heterozygote advantage) promotes the persistence of green and melanistic color morphs. The paper was accompanied by a News and Views piece on the role of balancing selection in the maintenance of variation.
This photo, taken by Moritz Muschick, shows green (unstriped) and melanistic Timema cristinae color morphs and appears on the cover of Molecular Ecology volume 26, issue 22.
Sam’s paper assessing determinants of variation in Lycaeides melissa caterpillar gut microbiomes is out now in Scientific Reports. We were interested in whether evolutionary or plastic changes in gut microbiome were critical in colonizing novel host plants. Our results presented in this paper suggest that this isn’t the case, and join a growing body of evidence pointing towards a more limited role of gut microbes in Lepidoptera in general (relative to other taxonomic groups where gut microbes are clearly important for growth and development).
You can listen to Sam discuss this work and her research more generally on this Slightly Evolved podcast.
Check out our new review paper on the ‘Analysis of Population Genomic Data from Hybrid Zones‘, which is now available on-line early from the Annual Review of Ecology, Evolution and Systematics.
This is a bit late, but several folks from the lab gave talks at the Evolution meeting in Portland this June. In case you missed them, here are links to video recordings on YouTube.
Lauren Lucas. Genetic constraints on wing pattern variation in Lycaeides butterflies.
Samridhi Chaturvedi. The predictability of genomic changes underlying a recent host shift.
Alex Rego. Genomic basis of rapid adaptation to a low quality host plant.
Amy Springer. Inbreeding depression in an ecological context.
Our paper on speciation in stick insects made the cover of Nature Ecology and Evolution (image by Moritz Muschick). In this paper we show how multiple factors come together for speciation to move from early to late stages of isolation and genomic differentiation, and we identify a distinct gap in genomic differentiation between con- and hetero-specific populations in sympatry.
You can read more about the paper in these blog and news articles:
Eco-evolutionary dynamics blog
We recently published a paper in Molecular Ecology Resources describing a method to determine ploidy in mixed ploidy samples from low to modest coverage GBS-like data (paper). This relies on both estimates of heterozygosity and allele specific read depth. The method we describe is implemented in the R package, gbs2ploidy. You can read more about it in this informative blog from the Molecular Ecologist.
Lauren’s paper on patterns and rates of gene flow within four narrowly endemic, spring-associated species is now out in Freshwater Biology. An image from the study of the amphipod Stygobromu made the cover (see above). The paper makes nice use of approximate Bayesian computation to contrast rates and models of gene flow among distantly related sympatric taxa.