BIOL 210 Lecture Notes - Sexual Reproduction, Multicellular Organism, Eukaryote
27 Sep 2014
School
Department
Course
Professor
Document Summary
Running with the red queen: host parasite coevolution selects for biparental sex. C. elegans: even smaller than a fruit fly! Are hemaphrodites but can"t fertilize other hermaphrodites. Do also produce, at a low frequency (1-30%) male offspring. Seek out hermaphrodites to transfer sperm, and do quite well. One half inocculated w/ seratia: highly pathogenic to nematodes. Experiments: create plates, bring worms and put onto nasty side of plate and look at number of worms that had made it the day before to the e. coli side. Different nasty sides: 1. no s. marcescens or killed strain, 2. fixed strain, 3. coevolving (grind up dead nematodes on assumption that bacteria inside these are more pathogenic) Suggests that there is genetic variation in these worms that is promoted by the challenge of the s. marcescens. Highly consistent w/ rq hypothesis: outcrossing benefits in the face of a continually evolving pathogen: obligate selfers, wildtype, obligate outcrossers.
