Supervisors: ddr hab. Łukasz Michalczyk, prof. UJ (l.michalczyk@uj.edu.pl)

Institute of Zoology and Biomedical Research

Background information:

The coexistence of sexual and asexual reproduction is a major conundrum in life sciences. While asexual reproduction offers clear advantages, such as avoiding the costs of producing males and reducing mating-related risks, theory and predicts and most observations confirm that sexual lineages should be more persistent due to the benefits of recombination and sexual selection. However, there are notable exceptions, ancient asexual lineages often termed as ‘evolutionary scandals’, such as bdelloid rotifers, oribatid mites or murrayid tardigrades, that challenge our understanding of evolution.

The main question to be addressed in the project:

Thus, the central question of this project is to understand why certain asexual lineages endure over geological time. Specifically, the project aims to investigate whether ancient asexuals have evolved compensatory genetic recombination mechanisms to counteract the loss of sexual reproduction.

Information on the methods/description of work:

To achieve its objectives, we will undertake a comprehensive comparative analysis of the genomic architecture of ancient and recent asexual tardigrade lineages. Recent advancements in genome sequencing techniques will facilitate the acquisition of tardigrade genomes from individual specimens, a substantial improvement over previous methodologies that required pooled samples of thousands of animals.

Additional information (e.g Special requirements from the student):

Documented experience with bioinformatics (preferably in genomics and/or transcriptomics) is strongly advantegous.

Place/name of potential foreign collaborator:

Wellcome Sanger Institute, Cambridge, UK/Prof. Mark Blaxter.

References:

[1] Brandt A. et al. (2021) Haplotype divergence supports long-term asexuality in the oribatid mite Oppiella nova. PNAS, 118: e2101485118. [https://doi.org/10.1073/pnas.2101485118]

[2] Laine V.N. et al. (2022) Genomic signature of sexual reproduction in the bdelloid rotifer Macrotrachella quadricornifera. Genetics, 220: iyab221. [https://doi.org/10.1093/genetics/iyab221]

[3] Vakrusheva O.A. et al. (2020) Genomic signatures of recombination in a natural population of the bdelloid rotifer Adineta vaga. Nature Communications, 11: 6421. [https://doi.org/10.1038/s41467-020-19614-y]