The article discusses the importance of rear edge populations in conserving biodiversity under climate change. It highlights that while expanding range margins have received significant attention, the low-latitude limits (rear edges) of species ranges are often overlooked. Rear edge populations, defined as those at the current low-latitude margins of species' distribution ranges, are crucial for long-term genetic diversity, phylogenetic history, and evolutionary potential. These populations are often disproportionately important for survival and evolution due to their unique ecological features and dynamics. The article reviews recent findings from the fossil record, phylogeography, and ecology to emphasize the need for dedicated research and conservation efforts. It also outlines three key areas for further development: identifying centers of relict diversity, integrating demographic and genetic work with modeling approaches, and designing appropriate conservation strategies that consider the peculiarities of rear edge populations. The article concludes by emphasizing the urgent need for more research and conservation measures to effectively preserve these relict populations.The article discusses the importance of rear edge populations in conserving biodiversity under climate change. It highlights that while expanding range margins have received significant attention, the low-latitude limits (rear edges) of species ranges are often overlooked. Rear edge populations, defined as those at the current low-latitude margins of species' distribution ranges, are crucial for long-term genetic diversity, phylogenetic history, and evolutionary potential. These populations are often disproportionately important for survival and evolution due to their unique ecological features and dynamics. The article reviews recent findings from the fossil record, phylogeography, and ecology to emphasize the need for dedicated research and conservation efforts. It also outlines three key areas for further development: identifying centers of relict diversity, integrating demographic and genetic work with modeling approaches, and designing appropriate conservation strategies that consider the peculiarities of rear edge populations. The article concludes by emphasizing the urgent need for more research and conservation measures to effectively preserve these relict populations.