Morphological change and phenotypic plasticity in native and non‐native pumpkinseed sunfish in response to sustained water velocities

Abstract

Phenotypic plasticity can contribute to the proliferation and invasion success of nonindigenous species by promoting phenotypic changes that increase fitness, facilitate range expansion and improve survival. In this study, differences in phenotypic plasticity were investigated using young-of-year pumpkinseed sunfish from colonies established with lentic and lotic populations originating in Canada (native) and Spain (non-native). Individuals were subjected to static and flowing water treatments for 80 days. Interand intra-population differences were tested using ANCOVA and discriminant function analysis, and differences in phenotypic plasticity were tested through a MANOVA of discriminant function scores. Differences between Iberian and North American populations were observed in dorsal fin length, pectoral fin position and caudal peduncle length. Phenotypic plasticity had less influence on morphology than genetic factors, regardless of population origin. Contrary to predictions, Iberian pumpkinseed exhibited lower levels of phenotypic plasticity than native populations, suggesting that canalization may have occurred in the non-native populations during the processes of introduction and range expansion.

Molecular investigation of mechanical strain-induced phenotypic plasticity in the ecologically important pharyngeal jaws of cichlid fish

“…On the other hand, putatively adaptive characteristics such as directional mouth asymmetry (Van Dooren et al., ) and pharyngeal jaw robustness and tooth size and shape in cichlids (Muschick et al., ; Gunter et al., ) result from mechanical strain due to food ingestion. Additionally, water velocity and exercise, which also exert mechanical stress on the skeleton, influence overall body shape in fish such as salmon, trout (Pakkasmaa and Piironen, ) and pumpkinseed sunfish (Robinson and Wilson, ; Yavno and Fox, ), in addition to influencing the rate of ossification in the skeleton (Pakkasmaa and Piironen, ; Grünbaum et al., ).…”

Water flow and fin shape polymorphism in coral reef fishes

“…As a result, fin and/or body shape may provide general assembly rules that predict fish community composition in wave-swept or high-flow habitats such as rivers and coral reefs (Bellwood and Wainwright 2001, Blake 2004, Langerhans 2008, Langerhans and Reznick 2010. Similar patterns of fin and/or body shape divergence related to water flow habitats have emerged within populations of widespread species due to local adaptation to the hydrodynamic environment or phenotypic plasticity (e.g., Pakkasmaa and Piironen 2001, Imre et al 2002, Langerhans et al 2003, Yavno and Fox 2013. But how widespread are these within-species patterns?…”

Shape plasticity in response to water velocity in the freshwater blenny Salaria fluviatilis

“…Water velocity can induce a functional phenotypic response in fishes, especially in locomotor-related traits such as fin size and body shape (Peres-Neto & Magnan, 2004;Proulx & Magnan, 2004;Grünbaum et al, 2007;Yavno & Fox, 2013;Senay et al, 2015). Under functional expectations, a slender body and caudal peduncle as well as smaller fins are expected when water velocity increases because they lead to decreased drag (Webb, 1982(Webb, , 1984Langerhans & Reznick, 2010).…”