Hello All. Being a microbiology professional and only a shell-collecting hobbiest I sometime back myself into a corner when I teach my Biodiversity course using mollusk examples. We were talking about genetics and a student asked me about species that change sex during their life. I thought immediately of Crepidula and passed along the little tidbits I know about the sex change involved in that species being driven by bio-chemical control from the bottom female. That isn't a whole lot to give them and it ignited more questions that I was left scratching my head on. So, I had no clue as to the chromosomal characteristics of this or for that matter any mollusk species. What are the chromosomal numbers like in most species? Any info on Crepidula? Normally what is the situation with sex-chromosomes in mollusks? female:male= XX:XY or XX:XO? Something else? ---------------------------------------------------------------------- [log in to unmask] - a forum for informal discussions on molluscs To leave this list, click on the following web link: http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1 Type your email address and name in the appropriate box and click leave the list. ----------------------------------------------------------------------