Napolitano Constanza, Díaz Diego, Sanderson Jim, Johnson Warren E, Ritland Kermit, Ritland Carol E, Poulin Elie
From the Laboratorio de Ecología Molecular, Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile (Napolitano and Poulin); Departamento de Ciencias Ambientales y Recursos Naturales, Facultad de Ciencias Agronómicas, Universidad de Chile, Santiago, Chile (Díaz); Small Wild Cat Conservation Foundation, Campbell, CA (Sanderson); Smithsonian Conservation Biology Institute, Front Royal, VA (Johnson); and Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada (K. Ritland and CE. Ritland).
J Hered. 2015;106 Suppl 1:522-36. doi: 10.1093/jhered/esv025.
Landscape fragmentation is often a major cause of species extinction as it can affect a wide variety of ecological processes. The impact of fragmentation varies among species depending on many factors, including their life-history traits and dispersal abilities. Felids are one of the groups most threatened by fragmented landscapes because of their large home ranges, territorial behavior, and low population densities. Here, we model the impacts of habitat fragmentation on patterns of genetic diversity in the guigna (Leopardus guigna), a small felid that is closely associated with the heavily human-impacted temperate rainforests of southern South America. We assessed genetic variation in 1798 base pairs of mitochondrial DNA sequences, 15 microsatellite loci, and 2 sex chromosome genes and estimated genetic diversity, kinship, inbreeding, and dispersal in 38 individuals from landscapes with differing degrees of fragmentation on Chiloé Island in southern Chile. Increased fragmentation was associated with reduced genetic diversity, but not with increased kinship or inbreeding. However, in fragmented landscapes, there was a weaker negative correlation between pairwise kinship and geographic distance, suggesting increased dispersal distances. These results highlight the importance of biological corridors to maximize connectivity in fragmented landscapes and contribute to our understanding of the broader genetic consequences of habitat fragmentation, especially for forest-specialist carnivores.
景观破碎化往往是物种灭绝的主要原因,因为它会影响多种生态过程。破碎化的影响因物种而异,这取决于许多因素,包括它们的生活史特征和扩散能力。猫科动物是受破碎化景观威胁最大的群体之一,因为它们的活动范围大、具有领地行为且种群密度低。在这里,我们模拟了栖息地破碎化对南美林猫(Leopardus guigna)遗传多样性模式的影响,南美林猫是一种小型猫科动物,与南美洲南部受人类影响严重的温带雨林密切相关。我们评估了1798个线粒体DNA序列碱基对、15个微卫星位点和2个性染色体基因的遗传变异,并估计了智利南部奇洛埃岛不同破碎化程度景观中38个个体的遗传多样性、亲缘关系、近亲繁殖和扩散情况。破碎化加剧与遗传多样性降低相关,但与亲缘关系增加或近亲繁殖增加无关。然而,在破碎化景观中,成对亲缘关系与地理距离之间的负相关较弱,这表明扩散距离增加。这些结果凸显了生物走廊对于在破碎化景观中最大化连通性的重要性,并有助于我们理解栖息地破碎化更广泛的遗传后果,特别是对于森林特化的食肉动物。