Repeated evolution of local adaptation in swimming performance: population-level trade-offs between burst and endurance swimming inBrachyrhaphisfreshwater fish

Abstract

Specialization is fundamentally important in biology because specialized traits allow species to expand into new environments, in turn promoting population differentiation and speciation. Specialization often results in trade‐offs between traits that maximize fitness in one environment but not others. Despite the ubiquity of trade‐offs, we know relatively little about how consistently trade‐offs evolve between populations when multiple sets of populations experience similarly divergent selective regimes. In the present study, we report a case study on Brachyrhaphis fishes from different predation environments. We evaluate apparent within/between population trade‐offs in burst‐speed and endurance at two levels of evolutionary diversification: high‐ and low‐predation populations of Brachyrhaphis rhabdophora, and sister species Brachyrhaphis roseni and Brachyrhaphis terrabensis, which occur in high‐ and low‐predation environments, respectively. Populations of Brachyrhaphis experiencing different predation regimes consistently evolved swimming specializations indicative of a trade‐off between two swimming forms that are likely highly adaptive in the environment in which they occur. We show that populations have become similarly locally adapted at both levels of diversification, suggesting that swimming specialization has evolved rather rapidly and persisted post‐speciation. Our findings provide valuable insight into how local adaptation evolves at different stages of evolutionary divergence.

Morphological predictors of swimming speed performance in river and reservoir populations of Australian smelt Retropinna semoni

“…Notably, our analyses indicated that neither standard length nor body shape were the strongest predictors of swimming speed performance, contrary to reported observations and theoretical predictions of morphological differentiation (Langerhans, 2008;Vogel, 1994;Webb, 1984). Indeed, body size and shape divergence may emerge in response to a range selective pressures imposed upon fish in different flow environments (Herler et al, 2010;Ingley et al, 2014;Ingley et al, 2016;Johnson et al, 2014).…”

Functional consequences of phenotypic variation between locally adapted populations: Swimming performance and ventilation in extremophile fish

“…These population differences in burst and steady swimming were evident in a functional trade‐off, where individuals with high fast‐start performance exhibited lower critical swimming speeds and vice versa . Functional trade‐offs between burst and steady swimming have been documented in poeciliids (Ingley et al, ; Langerhans, ) and other fishes (Ellerby & Gerry, ; Yan, He, Cao, & Fu, ) and underlie population differences in morphology when divergent selection favours different aspects of locomotion performance (Langerhans, Layman, Langerhans, & Dewitt, ). Fundamental constraints in combination with replicated environmental gradients may therefore be important contributors to convergent morphological evolution, both across independent lineages that have colonized H 2 S‐rich environments (Tobler et al, ) and in other systems (Ingley et al, ; Langerhans, ).…”

“…Methods for the quantification of fast-start responses were adapted from previous studies (Ingley, Camarillo, Willis, & Johnson, 2016;Langerhans et al, 2004). For each trial, we placed a fish into a clear acclimation cylinder (5.5 cm in diameter) within a larger test arena (circular tank with a 40 cm diameter).…”

Failed predator attacks have detrimental effects on antipredatory capabilities through developmental plasticity in Pelobates cultripes toads

“…Locomotor performance is positively related to survival (Husak, ; Teplitsky et al, ), and can improve prey hunting (Budick & O'Malley, ; Higham, ), optimize refuge use (Martín & López, ) and facilitate escape from predators (Arendt, ; McGee et al, ; Oufiero, Walsh, Reznick, & Garland, ). In fact, predator pressure selects for improved locomotor performance (Ingley, Camarillo, Willis, & Johnson, ): locomotor performance is increased in open areas, probably as a consequence of more intense predator pressure (Vanhooydonck & Van Damme, ).…”