host longevity and parasite species richness in mammals主机寿命和寄生在哺乳动物物种丰富度.pdfVIP

Host Longevity and Parasite Species Richness in Mammals Natalie Cooper1,2,3*, Jason M. Kamilar4,5, Charles L. Nunn1 1 Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America, 2 School of Natural Sciences, Trinity College Dublin, Dublin, Ireland, 3 Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin, Ireland, 4 Department of Anatomy, Midwestern University, Glendale, Arizona, United States of America, 5 School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, United States of America Abstract Hosts and parasites co-evolve, with each lineage exerting selective pressures on the other. Thus, parasites may influence host life-history characteristics, such as longevity, and simultaneously host life-history may influence parasite diversity. If parasite burden causes increased mortality, we expect a negative association between host longevity and parasite species richness. Alternatively, if long-lived species represent a more stable environment for parasite establishment, host longevity and parasite species richness may show a positive association. We tested these two opposing predictions in carnivores, primates and terrestrial ungulates using phylogenetic comparative methods and controlling for the potentially confounding effects of sampling effort and body mass. We also tested whether increased host longevity is associated with increased immunity, using white blood cell counts as a proxy for immune investment. Our analyses revealed weak relationships between parasite species richness and longevity. We found a significant negative relationship between longevity and parasite species richness for ungulates, but no significant associations in carnivores or primates. We also found no evidence for a relationsh