Food webs are ecological systems that include species interacting through consumptive relationships. Contrary to purely competitive systems, food webs can theoretically display very rich dynamics – from equilibrium to chaos –, and the occurrence of these dynamics largely depends on the value of species traits. In this context, the evolution of species traits is the result of a two-way process: on the one hand, trophic interactions set the stage for a complex adaptive landscape that shapes the distribution of species traits; on the other hand, evolving trait values affect the nature of food web dynamics and, thus, the pace and intensity of trophic interactions. This two-way process allows the emergence of intriguing phenomena such as “Red Queen” dynamics between host’s and parasite’s attributes (van Valen 1973) or the evolutionary building of abundance oscillations (Abrams & Matsuda 1997). More than thirty years after van Valen’s (1973) seminal paper, several major breakthroughs – theoretical and empirical – have pushed this field forward (e.g. van Baalen & Sabelis 1995; Abrams & Matsuda 1997; Caldarelli et al. 1998; Loeuille et al. 2002; Drossel & McKane 2003; Tokita & Yasutomi 2003; Yoshida et al. 2003; Hairston et al. 2005; Loeuille & Loreau 2005; Sabelis et al. 2005). The endeavor of this symposium is to bring together a very wide group of people actively working on the dynamical consequences of trait evolution in food webs to synthesize the state-of-the-art in this very quickly changing field. Speakers will consist of both theoreticians and empiricists, and of both renowned senior researchers and young scientists. The symposium will explore diverse questions linked to the evolution of traits in food webs, such as dispersal evolution, host-parasite dynamics, community diversification, food web structure, or the evolution of mating systems. The introduction and conclusion of the session will provide symposium attendees with an overview of current research on the dynamical consequences of trait evolution in food webs, and hopefully stir theoretical and empirical ideas on this topic.