Univ Gothenburg (Sweden) is seeking candidates for two PhD positions in Marine Evolution. Deadlines for both roles is 28 May 2021. The PhDs are:
PhD student position in Marine Sciences specializing in Evolutionary Genomics - Ecological systems biology: investigating the role of gene regulation in ecological speciation
The marine snail, Littorina saxatilis, has ecotypes that have evolved repeatedly in Sweden, United Kingdom and Spain, where a high-predation environment leads to a thick-shelled form and a high wave-action environment leads to a thin-shelled form. This PhD will be part of the Swedish Research Council Project: Ecological systems biology: disentangling the molecular mechanisms of ecological speciation. The goal of this project is to identify the genetic mechanisms responsible for these parallel phenotypes, specifically the shell phenotypes. We will examine the genetics of shell formation between ecotypes and assess the relative contribution of genetic vs plastic effects on gene expression in the mantle tissue. We will examine the regulatory architecture using gene expression, eQTLs, and open chromatin sequencing (ATACseq). We will synthesize these results along with other data available from members of the Littorina Research Group https://littorina.group.shef.ac.uk, including large-scale phenotyping, examination of hybrids, and whole-genome re-sequencing of L. saxatilis and related species.
2. PhD student position in Marine Sciences specializing in Evolutionary Biology - Spermatogenesis and sperm evolution in fish and marine invertebrates
Sperm cells are one of the most varied cell types across the animal kingdom which is surprising giving their universal function of fertilization of an egg. Many organisms, especially crustaceans, have vastly different morphology than the tadpole-like mammalian sperm that we typically think of as a sperm cell. Additionally, in the marine environment, many organisms have external fertilization, so the gametes can be affected by the external environment (salinity, pH, pollutants). Sperm are produced in the testes through the process of spermatogenesis, and germ cells proceed through several sequential steps before becoming a functional sperm cell. Due to the complexity of varied cell types that are present in testis tissue, very little is known about the cell biology and genetics of this process except in model organisms.
There are many interesting questions still to be addressed concerning spermatogenesis and sperm evolution in fish and marine invertebrates. The PhD thesis project can be developed according to the candidate’s interests. For example, research in this area can focus on sperm morphological variation across various taxa, histology and molecular characterization of cell types during spermatogenesis and the molecular bases of sperm morphology, sperm performance or testis development in response to environmental changes, sperm-egg interactions, reproductive isolation related to gametes or other relevant topic.