Working Group

The tree of sex – a comprehensive synthesis of sex determination systems in eukaryotes

PI(s): Doris Bachtrog (University of California, Berkeley)
Catherine Peichel (Fred Hutchinson Cancer Research Center)
Judith Mank (University of Oxford)
Start Date: 1-May-2011
End Date: 30-Apr-2013
Keywords: database, comparative methods, population genetics, mating systems, sexual selection

Sex is universal among most groups of eukaryotes, yet a remarkable diversity of sex determining (SD) mechanisms exists. The evolution of separate sexes has been accompanied by the acquisition of sex chromosomes many times across fungi, plants, and animals. The mechanism of SD has important evolutionary and ecological implications, yet we know little about how and why these systems have evolved repeatedly. Traditionally, studies of SD and sex chromosomes have focused on a few model systems that represent the terminal phase of evolution, but reveal little about their origination or transitions among systems. Recent advances in molecular genomics have created exciting new possibilities to study the causes and consequences of different modes of SD in diverse non-model species that represent the full range of sex chromosome evolution. The proposed working group will capitalize upon these opportunities and facilitate interaction among disparate disciplines engaged in studies of SD. We will develop a series of testable hypotheses based on theoretical predictions regarding the evolution of SD and compile existing data to develop an integrative database containing information on SD across the Tree of Life, with relevant genetic, ecological and life-history parameters. This will enable us to perform a series of comparative analyses to identify factors influencing SD systems. The proposed activities will promote synergies among researchers working on diverse organisms in order to distinguish broad, convergent trends from species-specific idiosyncracies, and identify novel aspects that will become significant targets for future investigations into the evolutionary forces driving the diversity of SD systems.