TY - JOUR
T1 - Intraspecific variation in aerobic and anaerobic locomotion
T2 - gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata) do not exhibit a trade-off between maximum sustained swimming speed and minimum cost of transport
AU - Svendsen, Jon Christian
AU - Tirsgård, Bjørn
AU - Cordero, Gerardo A.
AU - Steffensen, John Fleng
PY - 2015
Y1 - 2015
N2 - Intraspecific variation and trade-off in aerobic and anaerobic traits remain poorly understood in aquatic locomotion. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), both axial swimmers, this study tested four hypotheses: (1) gait transition from steady to unsteady (i.e., burst-assisted) swimming is associated with anaerobic metabolism evidenced as excess post exercise oxygen consumption (EPOC); (2) variation in swimming performance (critical swimming speed; U crit) correlates with metabolic scope (MS) or anaerobic capacity (i.e., maximum EPOC); (3) there is a trade-off between maximum sustained swimming speed (U sus) and minimum cost of transport (COTmin); and (4) variation in U sus correlates positively with optimum swimming speed (U opt; i.e., the speed that minimizes energy expenditure per unit of distance traveled). Data collection involved swimming respirometry and video analysis. Results showed that anaerobic swimming costs (i.e., EPOC) increase linearly with the number of bursts in S. aurata, with each burst corresponding to 0.53 mg O2 kg(-1). Data are consistent with a previous study on striped surfperch (Embiotoca lateralis), a labriform swimmer, suggesting that the metabolic cost of burst swimming is similar across various types of locomotion. There was no correlation between U crit and MS or anaerobic capacity in S. aurata indicating that other factors, including morphological or biomechanical traits, influenced U crit. We found no evidence of a trade-off between U sus and COTmin. In fact, data revealed significant negative correlations between U sus and COTmin, suggesting that individuals with high U sus also exhibit low COTmin. Finally, there were positive correlations between U sus and U opt. Our study demonstrates the energetic importance of anaerobic metabolism during unsteady swimming, and provides intraspecific evidence that superior maximum sustained swimming speed is associated with superior swimming economy and optimum speed.
AB - Intraspecific variation and trade-off in aerobic and anaerobic traits remain poorly understood in aquatic locomotion. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), both axial swimmers, this study tested four hypotheses: (1) gait transition from steady to unsteady (i.e., burst-assisted) swimming is associated with anaerobic metabolism evidenced as excess post exercise oxygen consumption (EPOC); (2) variation in swimming performance (critical swimming speed; U crit) correlates with metabolic scope (MS) or anaerobic capacity (i.e., maximum EPOC); (3) there is a trade-off between maximum sustained swimming speed (U sus) and minimum cost of transport (COTmin); and (4) variation in U sus correlates positively with optimum swimming speed (U opt; i.e., the speed that minimizes energy expenditure per unit of distance traveled). Data collection involved swimming respirometry and video analysis. Results showed that anaerobic swimming costs (i.e., EPOC) increase linearly with the number of bursts in S. aurata, with each burst corresponding to 0.53 mg O2 kg(-1). Data are consistent with a previous study on striped surfperch (Embiotoca lateralis), a labriform swimmer, suggesting that the metabolic cost of burst swimming is similar across various types of locomotion. There was no correlation between U crit and MS or anaerobic capacity in S. aurata indicating that other factors, including morphological or biomechanical traits, influenced U crit. We found no evidence of a trade-off between U sus and COTmin. In fact, data revealed significant negative correlations between U sus and COTmin, suggesting that individuals with high U sus also exhibit low COTmin. Finally, there were positive correlations between U sus and U opt. Our study demonstrates the energetic importance of anaerobic metabolism during unsteady swimming, and provides intraspecific evidence that superior maximum sustained swimming speed is associated with superior swimming economy and optimum speed.
KW - Journal Article
U2 - 10.3389/fphys.2015.00043
DO - 10.3389/fphys.2015.00043
M3 - Journal article
C2 - 25741285
SN - 1664-042X
VL - 6
JO - Frontiers in Physiology
JF - Frontiers in Physiology
M1 - 43
ER -