Biology Department, Duke University, Durham, NC 27708, USA
Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA 92697, USA.
J Exp Biol. 2019 Apr 4;222(Pt 7):jeb198085. doi: 10.1242/jeb.198085.
Measurements of energy use, and its scaling with size, are critical to understanding how organisms accomplish myriad tasks. For example, energy budgets are central to game theory models of assessment during contests and underlie patterns of feeding behavior. Clear tests connecting energy to behavioral theory require measurements of the energy use of single individuals for particular behaviors. Many species of mantis shrimp (Stomatopoda: Crustacea) use elastic energy storage to power high-speed strikes that they deliver to opponents during territorial contests and to hard-shelled prey while feeding. We compared the scaling of strike kinematics and energetics between feeding and contests in the mantis shrimp We filmed strikes with high-speed video, measured strike velocity and used a mathematical model to calculate strike energy. During contests, strike velocity did not scale with body size but strike energy scaled positively with size. Conversely, while feeding, strike velocity decreased with increasing size and strike energy did not vary according to body size. Individuals most likely achieved this strike variation through differential compression of their exoskeletal spring prior to the strike. analyses found that used greater velocity and energy when striking larger opponents, yet variation in prey size was not accompanied by varying strike velocity or energetics. Our estimates of energetics inform prior tests of contest and feeding behavior in this species. More broadly, our findings elucidate the role behavioral context plays in measurements of animal performance.
能量使用的测量及其与体型的关系是理解生物体完成各种任务的关键。例如，能量预算是竞赛和觅食行为模式中评估博弈论模型的核心。将能量与行为理论明确联系起来需要测量特定行为的个体能量使用情况。许多种螳螂虾（Stomatopoda：甲壳纲）利用弹性储能为高速冲击提供动力，这些冲击是它们在领地竞争中对对手施加的，也是在觅食时对硬壳猎物施加的。我们比较了螳螂虾在觅食和竞争中打击运动学和能量学的比例关系。我们用高速摄像机拍摄了打击动作，测量了打击速度，并使用数学模型计算了打击能量。在竞争中，打击速度与体型不成比例，但打击能量与体型呈正相关。相反，在觅食时，打击速度随着体型的增加而减小，而打击能量则不随体型变化。个体最有可能通过在打击前对其外骨骼弹簧进行差异压缩来实现这种打击变化。分析发现，在打击更大的对手时，使用了更大的速度和能量，而猎物大小的变化并没有伴随着打击速度或能量的变化。我们对能量学的估计为该物种的竞赛和觅食行为的先前测试提供了信息。更广泛地说，我们的发现阐明了行为背景在动物性能测量中的作用。
