Anatomy of a cline: dissecting anti-predatory adaptations in a marine gastropod along the U.S. Atlantic coast

The scope of anti-predatory adaptation is expected to be greater in warm than in cold environments. High temperatures lower the costs associated with the production and maintenance of energetically expensive traits and enable ecological interactions to intensify. We tested this hypothesis by characterizing the expression of anti-predatory morphology within a marine gastropod species (the knobbed whelk, Busycon carica) over a large (>1,400 km) geographic area that spans more than 10°C annual temperature variation. We also conducted experimental predation studies with a powerful durophagous predator, the stone crab (Menippe), to verify the anti-predatory advantages of a heavily ornamented shell morphology (e.g., increased thickness, pronounced spines), and we used repair scar data to assess clinal variation in selective pressure from predators. We predicted that repair scar rates would be greatest in warm southernmost latitudes, and that expression of energetically costly anti-predator...相较于寒冷环境，温暖环境中的反捕食适应性的演化范围预计更广。高温会降低与能量高消耗性状的产生和维持相关的成本，并促进生态相互作用的强化。我们以海洋腹足类物种棘螺（Busycon carica，俗称knobbed whelk）为研究对象，在跨度超过1400公里、年温度变化幅度超过10℃的广阔地理区域内，对其反捕食形态的表达特征进行了表征，以此验证上述假说。我们还针对一种强效食壳性捕食者——石蟹（Menippe）开展了实验捕食研究，以验证具强烈壳体装饰的形态（如壳体增厚、棘突显著）所具备的反捕食优势；同时，我们利用修复疤痕数据，评估了捕食者施加的选择压力的渐变变异特征。我们预测，修复疤痕发生率在最南部的温暖纬度区域将达到最高，且能量高消耗的反捕食……