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Climatic and evolutionary processes are inextricably linked to conservation. Avoiding extinction in rapidly changing environments often depends upon a species' capacity to adapt in the face of extreme selective pressures. Here, we employed exon capture and high‐throughput next‐generation sequencing to investigate the mechanisms underlying population structure and adaptive genetic variation in the koala (Phascolarctos cinereus), an iconic Australian marsupial that represents a unique conservation challenge because it is not uniformly threatened across its range. An examination of 250 specimens representing 91 wild source locations revealed that five major genetic clusters currently exist on a continental scale. The initial divergence of these clusters appears to have been concordant with the Mid‐Brunhes Transition (~430 to 300 kya), a major climatic reorganisation that increased the amplitude of Pleistocene glacial‐interglacial cycles. While signatures of polygenic selection and environmental adaptation were detected, strong evidence for repeated, climate‐associated range contractions and demographic bottleneck events suggests that geographically isolated refugia may have played a more significant role in the survival of the koala through the Pleistocene glaciation than in situ adaptation. Consequently, the conservation of genome‐wide genetic variation must be aligned with the protection of core koala habitat to increase the resilience of vulnerable populations to accelerating anthropogenic threats. Finally, we propose that the five major genetic clusters identified in this study should be accounted for in future koala conservation efforts (e.g., guiding translocations), as existing management divisions in the states of Queensland and New South Wales do not reflect historic or contemporary population structure. [ABSTRACT FROM AUTHOR]

The existence of the Kaputar Rock Skink, a morphologically distinct Egernia population restricted to the Nandewar Ranges in northern New South Wales, has been known for decades. However, no comprehensive description or diagnosis of the taxon has been published in the scientifc literature, and its distinctiveness largely assumed. As part of a study investigating the genetic diferentiation of faunal populations on the Nandewar Range, comparisons between the Kaputar Rock Skink and east Australian Egernia striolata-group species were undertaken. The results indicate that the Kaputar Rock Skink is a distinct genetic lineage, showing species-level divergence from other Egernia species. Field studies suggest the Kaputar Rock Skink is restricted to an extremely narrow band of rock habitat above 1000 m or more in elevation, and only occupies retreat and sheltering sites near clif edges or in areas of extensive outcropping rock. It now appears to be a cool-adapted species constrained to high elevation habitat by niche conservatism. Field studies suggest the availability of suitable habitat on the summit areas of the Nandewar Ranges is highly limited, making it vulnerable to several potentially threatening processes, including anthropogenic climate change. The name Contundo roomi was erected for the Kaputar Rock Skink by Wells & Wellington in 1985, and we recommend Egernia roomi (Wells & Wellington, 1985) as the name for the Kaputar Rock Skink. [ABSTRACT FROM AUTHOR]