Predictability of adaptation in the marine snail Littorina saxatilis
We welcome applications for a fully-funded 4-year PhD position at the Marine Research Centre (CIM) of the University of Vigo, to work within the project “Predictability of shell morphology and colour adaptation in intertidal marine gastropods” (EVOLPRED, PID2025-167933NB-I00), led by Emilio Rolán-Alvarez and Juan Galindo. The thesis will focus on the evolutionary ecology and genomics of the rough periwinkle Littorina saxatilis and will be co-supervised by Juan Galindo (CIM-UVigo) and Juan Gefaell (Lund University, Sweden).
The project
To what extent is evolution predictable? EVOLPRED tackles this classic question using an exceptional natural laboratory: the Rías Baixas. The Rías Baixas (Vigo, Pontevedra, Arousa and Muros) are four drowned river valleys flooded by the sea over the last 12,000 years. Each of them exhibits the same intertidal environmental gradients — from wave-exposed outer shores to sheltered, brackish inner shores — replicated on its northern and southern coasts, giving eight partially independent natural replicates.
Along each replicate gradient, L. saxatilis forms strikingly parallel clines in shell colour and morphology: nearly monomorphic lineata populations on exposed shores, fulva-dominated populations in the inner sheltered areas, and highly polymorphic populations in between. Our previous work has shown that these clines have remained stable for more than 50 years, that they are potentially mirrored by a second, distantly related gastropod (Nucella lapillus), and that predation against less cryptic morphs is a likely driver. However, the genetic basis of this variation and the demographic history behind it remain unknown.
The PhD project will address these gaps by combining, in a way that can be tailored to the interests and background of the candidate:
- Ecology and behaviour: field tethering experiments and controlled predation assays with crabs and fish in the aquaria of the ECIMAT marine station, plus objective quantification of shell and rock-substrate colour by reflectance spectrometry, multispectral photography and visual modelling.
- Population genomics: whole-genome sequencing of populations sampled along the cline in the four Rías, and genome-wide association analyses of shell colour, size, shape, thickness and sculpture, together with estimates of heritability, inbreeding and inbreeding depression.
- Experimental evolution: a long-term transplant of wave-exposed lineata snails into a sheltered locality, monitored phenotypically and genomically, to test whether adaptation follows the predicted trajectory in real time.
Candidate profile
We are looking for a highly motivated researcher with a strong interest in evolutionary biology, evolutionary ecology and/or population genomics, holding a Master’s degree in evolutionary biology, genetics, genomics, ecology, marine biology, bioinformatics, zoology or any related discipline.
Contact
For more information, download the complete job advertisement.
