01 Jun 2018

Post-Docs Wanted

Collaborative project: Diversity of the moss Physcomitrium pyriforme: significance of autopolyploidy within a phylogenomic and experimental framework.

PIs: Dr. Bernard Goffinet (University of Connecticut, Storrs;) & Dr. Matt Johnson (Texas Tech University, Lubbock).

Additional PI: Dr. Rafael Medina (Augustana College, Illinois).

We seek candidates with interest and experience in phylogenomics, bryophyte systematics and evolution of plant genomes (see project description below) to fill two research associate positions:

  1. University of Connecticut, Storrs: candidate would lead or supervise population sampling in the field and genomic library preparation, genome size, karyotype, and morphological characterization, and testing of reproductive isolation. Candidate is expected to mentor undergraduates seeking research opportunities.

  2. Texas Tech University, Lubbock: candidate would lead development of novel bioinformatics, data visualization, and phylogenetic methods for analysis of targeted sequencing data in polypoid species. Candidate will organize and lead a bioinformatics methods workshop and is expected to mentor undergraduates.

Salary: ± $48,000 plus health insurance

Duration: 1 year, renewable pending satisfactory progress.

Start dates: September 1, 2018 at UCONN and January 1, 2019 at Texas Tech.

Interested candidates should send a single pdf composed of their CV, personal statement highlighting their qualifications and research interests and contact information for three references to either Bernard Goffinet (bernard.goffinet@uconn.edu) or Matt Johnson (matt.johnson@ttu.edu). Review of applicants begins immediately.

Project abstract: Whole genome duplication or autopolyploidy occurred repeatedly during the evolution of land plants and likely act as a major driver of evolutionary change. When genome duplications first occur within species they potentially result in immediate reproductive isolation of autopolyploids within populations. Genome duplications may also trigger significant genomic restructuring, preventing meiotic pairing and hence interbreeding between two independent autopolyploids. Genome duplications are thus effective mechanisms of microevolutionary change and are expected to be frequent enough within species for some to give rise to new evolutionary lineages. Our project seeks to test whether shifts in ploidy are phylogenetically structured within a complex of cryptic moss species, the Physcomitrium pyriforme complex. This complex is widespread in North America and Europe. It harbors seven karyotypes worldwide and exhibits much morphological variation, as reflected by the 29 synonyms. These annual, bisexual and selfing mosses are easily grown, and genome doubling is readily induced in vitro from sporophytic tissue, enabling tests of reproductive isolation among wild and artificial autopolyploids. Our project addresses four inter-related objectives: (1) Reconstruct the phylogenomic relationships of 400 populations of P. pyriforme complex using targeted sequencing of 800 low-copy nuclear genes; (2) Characterize the karyotype and genome size of 400 populations of the P. pyriforme-complex across Europe, and infer frequencies of ploidal shifts within a phylogenomic hypothesis; (3) identify morphological signatures of artificial genome duplication and through comparison with wild populations test whether these erode through time; and (4) complement these inferences with experiments testing for reproductive isolation among wild and artificial polyploids and thereby for the evolutionary significance of autopolyploidy.