Welcome to Episode 27 of Slightly Evolved! This week our guest is Ghazal Alavioon, a PhD student at Uppsala University. Ghazal talks to us about her research on the evolutionary dynamics of sperm. We talk about how haploid selection is a underestimated component of fitness in animals, and its consequences for both evolutionary dynamics and fertility applications. As always you can contact us via email ([email protected]), Twitter (twitter.com/slightlyevolpod) or join on our Facebook group (www.facebook.com/groups/664596143711550/). Remember you can also subscribe on iTunes (itunes.apple.com/us/podcast/sligh…d1197890502?mt=2), and we would really appreciate it if you could leave a rating/comment there!Here is a link to the paper Ghazal references about fathers age and rate of de novo mutations: https://www.nature.com/nature/journal/v488/n7412/full/nature11396.html. You can read more about Ghazal's research from one of her recent papers here: http://www.pnas.org/content/114/30/8053.*Editorial note: at 13:49 and 13:59 "morphology" should instead be "motility".