Call for Abstracts *Closing Soon* We are excited to invite you to our Symposium on "Cooperation, Conflict and the Evolution of Socially Transferred Materials" at ESEB 2025 (17th-22nd August, Barcelona). Please note that the submission deadline is coming up: 25th April 2025 via https://eseb2025.com/call-for-abstracts/ Our invited speakers are: Jen Perry Department of Biology, St. Francis Xavier University, Canada Aileen Berasategui Amsterdam Institute for Life and Environment, Section Ecology & Evolution, VU Amsterdam, Netherlands Symposium abstract Many organisms have evolved to transfer materials to conspecifics which go beyond simple gametes or nutrients. These are defined as socially transferred materials and include components that have been metabolized by the donor and induce a direct physiological response in the receiver, bypassing sensory organs. Examples include components of milk, seminal fluids, skin secretions and regurgitate and may even extend to the transfer of symbiotic microbes, with the method of transfer itself ranging from active uptake by recipients (e.g. consumption of externally deposited spermatophores), passive transfer (e.g. in ejaculates or milk) or even forced transfer (as in various forms of hypodermic injection). Although these transfers benefit the donor, they can influence the fitness of the recipient in different ways, either positively or negatively. Hence, whilst many social transfers may originate in cooperation, they also provide significant scope for conflict when the evolutionary interests of donors and recipients diverge. This broad and emerging field of integrative biology contains many parallels and research opportunities in dramatically different transfer systems that have to date been studied in isolation, within their own scientific fields (ranging from evolutionary ecology, via dairy production to medicine). An important early goal of the nascent STM community is thus to connect researchers focusing on different transfers to foster cross-fertilization, and to collectively identify unifying concepts and experimental priorities for understanding their role in evolution. In this symposium, we therefore aim to showcase the wide diversity of biological phenomena that can usefully be captured by the framework of socially transferred materials, and to identify the commonalities and key differences in their origins, properties and evolutionary fates. The symposium is organized by the ESEB Special Topic Network on Socially Transferred Materials. Organizers Steve Ramm UMR 6553 ECOBIO, Universit� de Rennes, France Joris Koene Amsterdam Institute for Life and Environment (A-LIFE), VU Amsterdam, Netherlands Mariana Wolfner Department of Molecular Biology and Genetics, Cornell University, USA Symposium details: https://eseb2025.com/list-of-symposia/#S08 For more information about (and to join!) the Special Topic Network: https://www.socialtransfer.net Dr. Steven RAMM Chaire de Recherche Rennes M�tropole Chaire de Professeur Junior UMR 6553 ECOBIO - Ecosyst�mes, Biodiversit�, Evolution Universit� de Rennes Campus de Beaulieu 263 avenue G�n�ral Leclerc 35042 Rennes Cedex FRANCE steven.ramm@univ-rennes.fr https://ecobio.univ-rennes.fr/interlocuteurs/steven-ramm Steven Ramm (to subscribe/unsubscribe the EvolDir send mail to golding@mcmaster.ca)