Dispersal syndromes in challenging environments: A cross‐species experiment

Abstract

Dispersal is a central biological process tightly integrated into life-histories, morphology, physiology and behaviour. Such associations, or syndromes, are anticipated to impact the eco-evolutionary dynamics of spatially structured populations, and cascade into ecosystem processes. As for dispersal on its own, these syndromes are likely neither fixed nor random, but conditional on the experienced environment. We experimentally studied how dispersal propensity varies with individuals' phenotype and local environmental harshness using 15 species ranging from protists to vertebrates. We reveal a general phenotypic dispersal syndrome across studied species, with dispersers being larger, more active and having a marked locomotion-oriented morphology and a strengthening of the link between dispersal and some phenotypic traits with environmental harshness.

The significance of partial migration for food web and ecosystem dynamics

“…Simply put, if fewer individuals are migrating, fewer individuals are transferring processes and vectoring materials between ecosystems, which has implications for the ecosystems organisms depart and arrive to. Second, similar to dispersal (Cote et al, 2022;Raffard et al, 2022;Stevens et al, 2014), individual migratory behaviour is often correlated with morphological, behavioural, and/or physiological traits of individuals that shape the organisms' impact on food webs and ecosystems, for instance, altering predator-prey dynamics (Yoshida et al, 2003), nutrient cycles (Palkovacs et al, 2009), ecosystem structure (Bassar et al, 2010 and ecosystem functions (Harmon et al, 2009). Third, although the literature on the food web and ecosystem effects of migration generally assumes a direction of causality from organism movement to ecosystem dynamics (Bauer & Hoye, 2014), the fraction of the population undergoing migration can be influenced by ecological F I G U R E 1 Visual summary of three main impacts of partial migration (life cycle, seasonal or diel) rendering it significant to food web and ecosystem dynamics.…”

“…As the significance of migration‐ecosystem feedbacks is virtually unexplored, a critical, open question is as follows: under what conditions are migration‐ecosystem feedbacks positive versus negative and what can drive the sign to flip? Second, we need to develop theory integrating across the major impacts of partial migration we describe (net effects, trait‐mediated effects and migration‐ecosystem feedbacks), for example linking individual traits to food web and ecosystem responses (in analogy to dispersal syndromes; Cote et al, 2022, Raffard et al, 2022). We have presented strong evidence showing an individual's traits can shape its effect on ecosystems and influence its migratory propensity, but to what extent can traits mediate migration‐ecosystem feedbacks?…”

Life-history traits, pace of life and dispersal among and within five species ofTrichogrammawasps: a comparative analysis

“…The potential implications of context-dependence and especially density-dependence for this syndrome Building on this point, our study was indeed context-independent, with every female tested for a given trait being tested under the same low-density conditions (alone in the experimental design with a non-limiting host supply). Dispersal syndromes (Bonte & Dahirel, 2017;Cote et al, 2022;Ronce, 2012) but also pace-of-life syndromes can be context-dependent. Behavioural types can be dependent of the dispersal status and predation risks (Bell & Sih, 2007;Cote et al, 2010).…”

“…Finally, we allowed both dispersal and oviposition to occur at the same time, while Reznik and Klyueva (2006) and Lartigue et al (2022)’s setups were based on measuring dispersal/movement in the absence of hosts and presenting hosts to the wasps at another time. Dispersal is extremely context-dependent, including to current resource availability (Fronhofer et al, 2018); there is furthermore evidence that syndromes linking dispersal to other traits can be altered depending on whether individuals disperse from high-resource or low-resource contexts (Cote et al, 2022).…”

“…Dispersal syndromes (Bonte & Dahirel, 2017; Cote et al, 2022; Ronce, 2012) but also pace-of-life syndromes can be context-dependent. Behavioural types can be dependent of the dispersal status and predation risks (Bell & Sih, 2007; Cote et al, 2010).…”