The findings of this study shed light on the potential impacts of global climate change on Mus musculus and its subspecies in Asia, spanning from the last glacial maximum to the end of the 21st century. The utilization of Species Distribution Models (SDMs) based on a comprehensive dataset allowed us to examine the dynamic response of these small rodents to changing climatic conditions.
The examination of Mus musculus distribution during the last glacial maximum (LGM) provides valuable insights into the species' historical response to climate fluctuations. The observed increase in suitable habitats for M. m. musculus (MUS) and M. m. bactrianus (BAC) during LGM suggests a capacity for adaptation and range expansion in response to colder climatic conditions. This adaptive potential aligns with the general understanding that small rodents often exhibit behavioral and physiological adaptations to survive in diverse environments. The study's current condition (CC) models suggest that M. m. domesticus (DOM), M. m. musculus (MUS), and M. m. castaneus (CAS) face potential contractions in suitable habitats. This contraction is particularly evident in East Asia and South India for DOM, East Asia for CAS, and Japan for MUS. In contrast, M. m. bactrianus (BAC) shows an expansion of suitable habitats. These projections highlight the heterogeneity in responses among Mus musculus subspecies, emphasizing the need for nuanced conservation strategies.
The variable importance analysis underscores the role of temperature-related variables in shaping the distribution of Mus musculus. Annual Mean Temperature (Bio_1), Mean Diurnal Range (Bio_2), and Isothermality (Bio_3) were identified as key influencers during different periods. Notably, the increasing importance of temperature-related variables in future projections aligns with broader climate change patterns, suggesting that rising temperatures might become a predominant factor influencing the distribution of Mus musculus. The anticipated changes in Mus musculus distribution have ecological implications for Asia. The potential decrease in suitable habitats for some subspecies may impact ecosystem dynamics, affecting seed dispersal, predation, and serving as prey for larger predators. Furthermore, the observed shifts in distribution patterns may lead to altered interspecies interactions, potentially influencing the broader ecological network in which Mus musculus participates.
The high AUC values obtained for all models indicate the robustness and reliability of SDMs. This suggests that the models are effective in predicting the potential distributional changes of Mus musculus under different climatic scenarios. Despite the rigor in data processing and quality control, limitations exist in the availability of occurrence data. Incorporating more fine-scale data and continuous monitoring efforts could enhance the precision of future SDMs. Additionally, the reliance on SDMs assumes that species' responses are solely climate-driven, not accounting for potential anthropogenic influences or interactions with other species.
Given the varied responses of Mus musculus subspecies to climate change, conservation efforts should adopt a differential approach. Subspecies facing habitat contractions might require targeted conservation strategies, including habitat restoration, while those experiencing habitat expansions may need monitoring to manage potential overpopulation and associated ecological impacts. Identifying areas with relatively stable conditions, such as potential climatic refugia, becomes crucial for conservation planning. Conservation efforts focused on protecting these refugial areas could serve as a strategy to safeguard Mus musculus populations in the face of changing climates.