Data from: Higher predation risk for insect prey at low latitudes and elevations

Biotic interactions underlie ecosystem structure and function, but predicting interaction outcomes is difficult. We tested the hypothesis that biotic interaction strength increases toward the equator, using a global experiment with model caterpillars to measure predation risk. Across an 11,660-kilometer latitudinal gradient spanning six continents, we found increasing predation toward the equator, with a parallel pattern of increasing predation toward lower elevations. Patterns across both latitude and elevation were driven by arthropod predators, with no systematic trend in attack rates by birds or mammals. These matching gradients at global and regional scales suggest consistent drivers of biotic interaction strength, a finding that needs to be integrated into general theories of herbivory, community organization, and life-history evolution.

生物种间相互作用是生态系统结构与功能的核心基础，但精准预测相互作用的结果却极具挑战。本研究通过开展全球尺度野外实验，以模拟毛虫（model caterpillars）为实验材料量化捕食风险，验证了“生物相互作用强度随纬度趋近赤道而增强”这一科学假说。在横跨六大洲、全长11660公里的纬度梯度范围内，我们观测到捕食压力随纬度趋近赤道逐渐升高，同时伴随海拔降低，捕食压力同步上升的平行格局。上述纬度与海拔梯度上的捕食格局均由节肢动物捕食者（arthropod predators）主导，而鸟类与哺乳类的攻击率未呈现系统性变化趋势。全球与区域尺度下均观测到的一致梯度格局，表明生物种间相互作用强度存在统一的驱动机制；这一发现亟需被纳入植食作用（herbivory）、群落组织（community organization）以及生活史进化（life-history evolution）的通用理论框架之中。