Play is an important component of development in a range of mammalian species, and may provide adaptive benefits for young individuals in some cases. We evaluated the hypothesis that social play in juvenile Belding’s ground squirrels (Urocitellus beldingi) promotes development of cautious responses when individuals are confronted with a potential threat. We observed the play behavior of juvenile U. beldingi across the developmental period in which play primarily occurs. To measure caution, we conducted behavioral tests on individual squirrels at the beginning and toward the end of the play period, and again when the individuals were yearlings. During tests we recorded the distances at which squirrels first noticed and fled from a human intruder. In initial tests, juveniles with yearling mothers responded to intruders at greater distances than did juveniles with older mothers suggesting maternal effects on the development of caution. Distances at which juveniles noticed and fled from an intruder increased across the play interval, suggesting increased caution to a potential threat as early development progresses. Social play was a reliable predictor of increases in caution, with juveniles who engaged in social play at higher rates having greater increases in the distance to notice and flee from an intruder. Distances to flee from an intruder at the end of the play interval were reliable predictors of distances to flee from an intruder as a yearling, suggesting consistency in cautious responses among individual U. beldingi over time. Rates of social play as a juvenile were reliable predictors of distances to notice and flee from an intruder as a yearling, suggesting that possible influences of play behavior on cautious responses extend beyond the juvenile period.

中文翻译：

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社交游戏预示幼年贝尔丁地松鼠 (Urocitellus beldingi) 的谨慎

游戏是一系列哺乳动物物种发育的重要组成部分，在某些情况下可能为幼年个体提供适应性益处。我们评估了这样的假设：幼年贝尔丁地松鼠（Urocitellus beldingi）的社交游戏促进个体在面临潜在威胁时做出谨慎反应。我们观察了青少年 U.beldingi 在玩耍主要发生的发育时期的玩耍行为。为了衡量谨慎程度，我们在游戏开始和结束时对个别松鼠进行了行为测试，并在松鼠一岁的时候再次进行了行为测试。在测试过程中，我们记录了松鼠第一次注意到人类入侵者并逃离的距离。在最初的测试中，与年长母亲的青少年相比，一岁母亲的青少年对入侵者的反应距离更远，这表明母亲对谨慎发展的影响。在游戏期间，青少年注意到并逃离入侵者的距离不断增加，这表明随着早期发育的进展，对潜在威胁的警惕性越来越高。社交游戏是谨慎程度增加的可靠预测因素，参与社交游戏频率较高的青少年，注意到并逃离入侵者的距离会增加更大。在游戏间隔结束时逃离入侵者的距离是一岁幼鸟逃离入侵者的距离的可靠预测因素，这表明随着时间的推移，各个贝尔丁吉人的谨慎反应是一致的。