Brad Anholt, Director of Bamfield Marine Sciences Centre (bamfieldmsc.com) and Canada Research Chair University of Victoria will present the Department of Statistical Science's seminar, with a talk entitled, "Sex without sex chromosomes:  extraordinary sex-ratios in a marine crustracean".

Why sex ratio is usually 1:1 at conception is one of the great success stories of evolutionary biology.  It successfully predicts the observed sex-ratio of ants and wasps with their haplo-diploid sex determination mechanisms, and deviations from 1:1 that occur due to inbreeding. For organisms with sex chromosomes, sex-ratio is very precisely determined to be 1:1 within the limits of binomial sampling.  For those without sex-chromosomes things are more interesting. 

In this talk Brad will describe their studies of sex determination in Tigriopus californicus, a small marine copepod (Crustacea).  I will highlight some of the more challenging sampling problems and error distributions that contributed to my decision to spend some time in your department.