Competition for resources shapes ecological and evolutionary relationships. Physiological capacities such as in locomotor performance can influence the fitness of individuals by increasing competitive success. Social hierarchy too can affect outcomes of competition by altering locomotor behaviour or because higher ranking individuals monopolize resources. Here, we tested the hypotheses that competitive success is determined by sprint performance or by social status. We show that sprint performance of individuals measured during escape responses (fast start) or in an accelerated sprint test did not correlate with realized sprint speed while competing for food within a social group of five fish; fast start and accelerated sprint speed were higher than realized speed. Social status within the group was the best predictor of competitive success, followed by realized speed. Social hierarchies in zebrafish are established within 7 days of their first encounter, and interestingly, there was a positive correlation between social status and realized speed 1 and 4 days after fish were placed in a group, but not after 7 days. These data indicate that physiological performance decreases in importance as social relationships are established. Also, maximal physiological capacities were not important for competitive success, but swimming speed changed with social context.

资源竞争塑造了生态和进化的关系。运动能力等生理能力可通过提高竞争成功率来影响个人的身体素质。社会等级制度也可能通过改变运动行为或由于较高的个人垄断资源而影响竞争的结果。在这里，我们检验了以下假设：竞争成功是由冲刺表现或社会地位决定的。我们显示，在争夺五条鱼的社会群体中的食物时，在逃跑响应（快速启动）或加速冲刺测试中测得的个人的冲刺表现与实现的冲刺速度不相关。快速启动和加速的冲刺速度高于实现速度。小组中的社会地位是竞争成功的最好预测，其次是实现的速度。斑马鱼的社会等级是在第一次接触后的7天内建立的，有趣的是，在将鱼放入一组后的1-4天，社会地位与实现速度之间存在正相关，而在7天之后则没有。这些数据表明，随着社会关系的建立，生理机能的重要性降低。同样，最大的生理能力对竞争成功并不重要，但游泳速度随社交环境而变化。这些数据表明，随着社会关系的建立，生理机能的重要性降低。同样，最大的生理能力对竞争成功并不重要，但游泳速度随社交环境而变化。这些数据表明，随着社会关系的建立，生理机能的重要性降低。同样，最大的生理能力对竞争成功并不重要，但游泳速度随社交环境而变化。