University of Colorado, Boulder, Colorado 80309, USA.
Ecology. 2011 Mar;92(3):542-8. doi: 10.1890/10-0516.1.
Parasites can cause dramatic changes in the phenotypes of their hosts, sometimes leading to a higher probability of predation and parasite transmission. Because an organism's morphology directly affects its locomotion, even subtle changes in key morphological traits may affect survival and behavior. However, despite the ubiquity of parasites in natural communities, few studies have incorporated parasites into ecomorphological research. Here, we evaluated the effects of parasite-induced changes in host phenotype on the habitat use, thermal biology, and simulated predator-escape ability of Pacific chorus frogs (Pseudacris regilla) in natural environments. Frogs with parasite-induced limb malformations were more likely to use ground microhabitats relative to vertical refugia and selected less-angled perches closer to the ground in comparison with normal frogs. Although both groups had similar levels of infection, malformed frogs used warmer microhabitats, which resulted in higher body temperatures. Likely as a result of their morphological abnormalities, malformed frogs allowed a simulated predator to approach closer before escaping and escaped shorter distances relative to normal frogs. These data indicate that parasite-induced morphological changes can significantly alter host behavior and habitat use, highlighting the importance of incorporating the ubiquitous, albeit cryptic, role of parasites into ecomorphological research.
寄生虫可以显著改变宿主的表型，有时会增加被捕食和寄生虫传播的概率。由于生物体的形态直接影响其运动能力，即使关键形态特征发生微小变化，也可能影响其生存和行为。然而，尽管寄生虫在自然群落中普遍存在，但很少有研究将寄生虫纳入生态形态学研究中。在这里，我们评估了宿主表型被寄生虫改变对太平洋角蟾（Pseudacris regilla）在自然环境中的栖息地利用、热生物学和模拟捕食者逃避能力的影响。与正常青蛙相比，感染后肢体畸形的青蛙更有可能利用地面微生境，而不是垂直避难所，并选择更接近地面的角度较小的栖息点。尽管两组的感染水平相似，但畸形青蛙利用更温暖的微生境，导致体温升高。可能是由于它们的形态异常，畸形青蛙在逃跑前允许模拟捕食者更接近它们，并且与正常青蛙相比，它们逃跑的距离更短。这些数据表明，寄生虫引起的形态变化可以显著改变宿主的行为和栖息地利用，突出了将寄生虫普遍存在但隐蔽的作用纳入生态形态学研究的重要性。
