Mitogenomic resolution of phylogenetic conflicts and adaptive signatures in feliform carnivorans

Abstract

Feliform carnivores face dual threats from habitat fragmentation and climate change, but unresolved phylogenetic relationships and unclear adaptive mechanisms hinder the development of conservation strategies. This study integrates mitochondrial genome data from 75 extant species (including three newly obtained taxa: Helogale parvula, Suricata suricatta, and Neofelis diardi) to resolve taxonomic controversies and reveal adaptive evolutionary mechanisms. Bayesian phylogenetic reconstruction strongly supports a sister-group relationship between Felidae and Prionodontidae (posterior probability PP = 1.0), overturning traditional morphological classifications. Divergence time estimation indicates that the crown group of Feliformia originated in the Middle Eocene (46 Ma), with key radiation events synchronized with Oligocene-Miocene climatic upheavals and continental collisions. Adaptive evolution analyses show that mitochondrial protein-coding genes (PCGs) are predominantly under purifying selection. However, significant positive selection signals were detected in the ND4 gene of Nandinia binotata and the COX2 gene of Pantherinae, potentially linked to arid adaptation and predatory energy demands, respectively. The frequent use of GTG start codons in the COX1 gene of Neofelis diardi suggests metabolic fine-tuning for island ecosystems. Conservation genomics identifies Prionodon pardicolor and Neofelis nebulosa as Evolutionarily Significant Units (ESUs) with heightened vulnerability to habitat fragmentation. By integrating mitogenomic architecture, deep-time biogeography, and contemporary selection pressures, this study establishes a unified framework bridging molecular systematics and conservation strategies, providing scientific guidance for protecting rapidly evolving lineages.