Abstract:
Big cats, such as Amur tigers (Panthera tigris altaica) and Amur leopards (P. pardus orientalis), are top predators that have evolved specialized traits for hunting and carnivory (Fernandez Moya et al., 2021). They play a crucial role in maintaining biodiversity and ecosystem integrity by balancing prey-predator dynamics. However, human activities, including habitat fragmentation and environmental changes, have led to the persistence of these big cats in small and isolated populations. Currently, all living big cats are categorized as endangered or threatened. Amur tigers and Amur leopards share overlapping geographic ranges, habitats, and some prey in the forests of Northeast Asia (Jiang et al., 2015). To reduce conflict between the two species, they exhibit differentiated dietary and temporal 36 niches. Tigers prefer large ungulates, while leopards hunt small to medium-sized prey (Kerley et al., 2015; Sugimoto et al., 2016). They also occupy different niches temporally, with tigers being active at night and leopards active during the day. Despite spatial and temporal partitioning, interspecific competition between Amur tigers and Amur leopards remains inevitable. Tigers have a competitive advantage due to their larger size, and competition takes various forms, including occasional leopard predation by tigers and declines in leopard populations with increasing tiger density (Donadio and Buskirk, 2006; Jiang et al., 2015). Tigers also exclude leopards from marginal habitats in nature reserves where they coexist. The coexistence and competition between these big cats involve not only ecological factors but also genetic factors underlying physiological traits. However, the genetic basis for co-adaptation and competition has not been well studied. In this study, we assembled a haplotype-resolved and chromosome-scale genome for a wild Amur leopard without the parental information and conducted comparative genomic analysis with an Amur tiger genome to elucidate the genetic basis for coexistence and competition. This research has implications for the future conservation of these two endangered species.
