Call for talks and posters for a symposium on "Letting go: reductive evolution across the tree of life" (Symposium S32) at ESEB 2025 The ESEB 2025 Congress will be held at the International Convention Centre of Barcelona (CCIB) in Barcelona, Spain, from August 17 to 22,2025. Letting go: reductive evolution across the tree of life Evolution has been characterized by a series of major morphological innovations, often associated with the gain of genomic novelty. Gene gains have played a fundamental role in the origins of animals and land plants, while genome duplication has driven the diversification of vertebrates and flowering plants. However, evolution does not always result in greater complexity. The role of loss in evolution, by contrast, remains relatively underexplored. Aided by sophisticated omics data and advanced analytical techniques, the prevalence and significance of reductive events in evolutionary history are being elucidated. Recent research has revealed that groups such as bryophytes, fungi, and tardigrades have undergone significant gene loss and genome simplification, shaping their evolutionary trajectories. In this symposium, we will explore this important but overlooked evolutionary process. Our speakers will present recent studies that shed light on the role of reductive evolution across the tree of life. This symposium also provides a timely opportunity to highlight and discuss the mechanisms of reductive evolution across diverse taxonomic groups, offering new perspectives on how simplification can be as crucial to evolution as complexity. We have two exciting invited speakers to this symposium, namely Rosa Fern�ndez (Institute of Evolutionary Biology, Barcelona, Spain) and Sven Gould (Heinrich-Heine-Universit�t, D�sseldorf, Germany). Deadline for abstract submission: 25 April 2025. For more information and to submit your abstract, please visit: https://eseb2025.com/call-for-abstracts/ We look forward to seeing you in Barcelona in August 2025. Best wishes, Dr. Alexander Bowles, University of Oxford (alex.bowles@biology.ox.ac.uk) Dr. James Clark, University of Bath (jc493@bath.ac.uk) Alex Bowles (to subscribe/unsubscribe the EvolDir send mail to golding@mcmaster.ca)