Schadegg Abigail C, Herberholz Jens
Department of Psychology, University of Maryland, College Park, MD, 20742, USA.
Neuroscience and Cognitive Science Program, University of Maryland, College Park, MD, 20742, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2017 Mar;203(3):223-232. doi: 10.1007/s00359-017-1158-8. Epub 2017 Feb 28.
Moving shadows signify imminent threat to foraging juvenile crayfish, and the animals respond with one of two discrete anti-predatory behaviors: They either freeze in place or rapidly flex their tails, which quickly propels them away from the approaching danger signal. Although a freeze might be the more risky choice, it keeps the animal near the expected food reward, while a tail-flip is effective in avoiding the shadow, but puts critical distance between the animal and its next meal. We manipulated the satiation level of juvenile crayfish to determine whether their behavioral choices are affected by internal energy states. When facing the same visual danger signal, animals fed to satiation produced more tail-flips and fewer freezes than unfed animals, indicating that intrinsic physiological conditions shape value-based behavioral decisions. Escape tail-flip latencies, however, were unaffected by satiation level, and an increase in food quality only produced a minor behavioral shift toward more freezing in both fed and unfed animals. Thus, satiation level appears to be the dominant factor in regulating decision making and behavioral choices of crayfish.
移动的阴影意味着对觅食幼小龙虾的紧迫威胁，这些动物会通过两种不同的反捕食行为之一做出反应：它们要么原地不动，要么迅速摆动尾巴，这会迅速将它们从接近的危险信号中推开。虽然静止不动可能是风险更高的选择，但它能让动物靠近预期的食物奖励，而尾部翻转在避开阴影方面很有效，但会使动物与其下一顿食物之间拉开关键距离。我们操纵了幼小龙虾的饱腹感水平，以确定它们的行为选择是否受内部能量状态的影响。当面对相同的视觉危险信号时，饱腹的动物比未进食的动物产生更多的尾部翻转和更少的静止不动，这表明内在生理状况塑造了基于价值的行为决策。然而，逃避性尾部翻转潜伏期不受饱腹感水平的影响，食物质量的提高仅在进食和未进食的动物中都产生了轻微的行为转变，即更多地静止不动。因此，饱腹感水平似乎是调节小龙虾决策和行为选择的主导因素。
