New paper out in Ecology Letters with Katja Tielbörger, Amaël Daval, and Charles Mullon 🥳!
Using eco-evolutionary models of annual plants, we show that adaptive plasticity in seed germination promotes genetic diversification and ecological speciation.
Announcing 🍱 Lunchbox Models 🍱
– an online seminar series all about ecological modelling & career insights, hosted by the @gfoe AKs Computational Ecology and YoMos 🦊
Happening each last Wednesday of the month during lunch break, starting from 29th of October!
Find the topics and details as well as access to Zoom on our webpage: https://www.yomos.org/lunchbox-models-seminar-series
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#Academia #Ecology #PhD #Postdoc #LunchboxModels #Modelling #Theory #PhdLife #seminar #science
Temporal fluctuations in environmental conditions can promote coexistence via the storage effect, which requires a mechanism buffering different variants during adverse periods. This mechanism readily occurs in annual plants whose seeds do not necessarily germinate each year but instead remain dormant in a seed bank. Yet, how plasticity in germination timing affects genetic diversification and ecological speciation under temporally varying conditions remains poorly understood. Here, we use mathematical modeling and individual-based simulations to investigate the joint evolution of a combination of traits controlling plastic seed germination and plant fecundity under interannual environmental fluctuations. We show that adaptive plasticity in germination readily evolves via a genetic association between seed and plant traits, allowing seeds to germinate preferentially in years favorable for their subsequent growth and reproduction. Such adaptive plasticity enhances the storage effect and promotes genetic divergence among different morphs specialized to distinct yearly conditions. Because these morphs germinate preferentially in different years, plastic germination indirectly generates temporal assortative mating, thereby maintaining genetic associations among seed and plant traits despite the absence of physical linkage between loci controlling these traits. This temporal assortative mating ultimately leads to reproductive isolation between morphs, thus laying the foundation for ecological speciation. Our findings show that adaptive plasticity and genetic diversification are not mutually exclusive but can interact synergistically to enhance biodiversity. ### Competing Interest Statement The authors have declared no competing interest. German Academic Exchange Service, https://ror.org/039djdh30, SAGE Centre
Schmid et al. shed light on the nature of selection and drivers of polymorphism by studying how resource variation within and between habitats shapes consumer variation. Read now ahead of print!
https://www.journals.uchicago.edu/doi/10.1086/727483
We adopted a landscape-scale approach to analyze the genetic patterns (diversity, structure, and differentiation) of the Marbled White (Melanargia galathea). This butterfly species is characteristic of semi-dry grasslands, which have substantially declined in Switzerland during past decades. We sampled individuals on a regular grid of the established Biodiversity Monitoring program of Switzerland over five consecutive years, obtaining 1639 genotyped individuals from 185 locations. Results showed that M. galathea populations cluster into five spatially aggregated clusters that largely coincide with the biogeographic regions of Switzerland. Genetic diversity (allelic richness) was higher in the South of the Alps, likely related to immigration dynamics that suggest recolonisation from the South after the last glaciation. Demographic history resulted in distinct isolation by distance (IBD) and by cumulative elevational difference (isolation by altitude, IBA) at large scale, while regional IBD and IBA were less pronounced. This pattern was likely induced by the barrier effect of the high mountains of the Alps impeding continuous northward migration after the last glacial maximum. A temporal analysis revealed that regional genetic diversity did not change strongly during the five sampling years. This result indicates that the genetic diversity pattern in M. galathea has not been noticeably affected by historical land-use change or that the sampling period of five years is too short to detect any changes. Our findings highlight the regionally, topography-induced distinct genetic clusters, relevant for consideration as conservation units and likely reflecting genetic structures similar to those found in other butterfly species of conservation concern.
Young Modellers in Ecology
bioRxiv Evobio
Fred Guillaume
Luis-Miguel Chevin
American Naturalist