Forsatkar Mohammad Navid, Nematollahi Mohammad Ali, Biro Peter A, Beckmann Christa
University of Tehran, Faculty of Natural Resources, Department of Fisheries, Karaj, Iran.
Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University, Geelong, Vic., Australia.
Physiol Behav. 2016 Oct 15;165:267-72. doi: 10.1016/j.physbeh.2016.08.007. Epub 2016 Aug 9.
Temperature has profound effects on physiology of ectothermic animals. However, the effects on temperature variation on behavioral traits are poorly studied in contrast to physiological endpoints. This may be important as even small differences in temperatures have large effects on physiological rates including overall metabolism, and behavior is known to be linked to metabolism at least in part. The primary aim of this study was to determine the effects of ambient temperature on boldness responses of a species of fish commonly used in behavioral experiments, the Siamese fighting fish (Betta splendens). At 26°C, subjects were first examined for baseline behaviors over three days, using three different (but complementary) 'open field' type assays tested in a fixed order. Those same fish were next exposed to either the same temperature (26°C) or a higher temperature (30°C) for 10days, and then the same behavioral assays were repeated. Those individuals exposed to increased temperatures reduced their latency to leave the release area (area I), spent more time in area III (farthest from release area), and were more active overall; together we infer these behaviors to reflect an increase in general 'boldness' with increased temperature. Our results add to a limited number of studies of temperature effects on behavioral tendencies in ectotherms that are evident even after some considerable acclimation. From a methodological perspective, our results indicate careful temperature control is needed when studying behavior in this and other species of fish.
温度对外温动物的生理机能有着深远影响。然而，相较于生理指标，温度变化对行为特征的影响却鲜有研究。这一点或许很重要，因为即使温度上的微小差异也会对包括整体新陈代谢在内的生理速率产生重大影响，而且众所周知行为至少在一定程度上与新陈代谢相关联。本研究的主要目的是确定环境温度对行为实验中常用的一种鱼类——暹罗斗鱼（Betta splendens）的大胆反应的影响。在26°C时，首先对实验对象进行为期三天的基线行为观察，采用三种不同（但相互补充）的“旷场”类试验，并按固定顺序进行测试。接下来，将这些鱼置于相同温度（26°C）或更高温度（30°C）下10天，然后重复相同的行为测试。那些暴露于较高温度下的个体缩短了离开释放区（区域I）的潜伏期，在区域III（离释放区最远）花费了更多时间，并且总体上更活跃；我们据此推断这些行为反映出随着温度升高，总体“大胆程度”增加。我们的研究结果补充了数量有限的关于温度对变温动物行为倾向影响的研究，即便经过相当长时间的驯化，这种影响依然明显。从方法学角度来看，我们的结果表明，在研究这种鱼类及其他鱼类的行为时，需要仔细控制温度。
