dictyNews Electronic Edition Volume 41, number 10 May 15, 2015 Please submit abstracts of your papers as soon as they have been accepted for publication by using the form at http://dictybase.org/db/cgi-bin/dictyBase/abstract_submit. Back issues of dictyNews, the Dicty Reference database and other useful information is available at dictyBase - http://dictybase.org. Follow dictyBase on twitter: http://twitter.com/dictybase ========= Abstracts ========= Elizabeth Ostrowski, Yufeng Shen, Xiangjun Tian, Richard Sucgang, Huaiyang Jiang, Jiaxin Qu, Mariko Katoh-Kurasawa, Debra Brock, Christopher Dinh, Fremiet Lara-Garduno, Sandra Lee, Christie Kovar, Huyen Dinh, Viktoriya Korchina, Laronda Jackson, Shobha Patil, Yi Han, Leslie Chaboub, Gad Shaulsky, Donna Muzny, Kim Worley, Richard Gibbs, Stephen Richards, Adam Kuspa, Joan Strassmann, and David Queller. Genomic signatures of cooperation and conflict in the social amoeba. Current Biology, in press. Cooperative systems are susceptible to invasion by selfish individuals that profit from receiving the social benefits but fail to contribute. These so-called ÒcheatersÓ can have a fitness advantage in the laboratory, but it is unclear whether cheating provides an important selective advantage in nature. We used a population genomic approach to examine the history of genes involved in cheating behaviors in the social amoeba Dictyostelium discoideum, testing whether these genes experience rapid evolutionary change as a result of conflict over spore-stalk fate. Candidate genes and surrounding regions showed elevated polymorphism, unusual patterns of linkage disequilibrium, and lower levels of population differentiation, but they did not show greater between-species divergence. The signatures were most consistent with frequency-dependent selection acting to maintain multiple alleles, suggesting that conflict may lead to stalemate rather than an escalating arms race. Our results reveal the evolutionary dynamics of cooperation and cheating and underscore how sequence-based approaches can be used to elucidate the history of conflicts that are difficult to observe directly. Submitted by Elizabeth Ostrowski [eaostrowski@uh.edu] ============================================================== [End dictyNews, volume 41, number 10]