A small leaf-eared mouse has adapted to survive on a high-altitude Andean volcano, where the harsh conditions challenge human existence. Researchers from McMaster University participated in a study published in the journal Science, revealing the mouse’s ability to generate heat efficiently in low-oxygen environments and process toxic plants as food.
The mouse species, Phyllotis vaccarum, thrives on the summit of Volcán Llullaillaco, facing oxygen levels significantly lower than at sea level. Despite the inhospitable environment, these mice have demonstrated remarkable survival capabilities, astonishing scientists.
Spanning from sea level to elevations exceeding 6,700 meters, these mice have the broadest elevation range among mammals. The research compared the genetic makeup of mice from different elevations and tested their heat production abilities under varying oxygen levels. Highland mice outperformed lowland counterparts and displayed better heat production efficiency, a critical advantage in freezing temperatures.
Highland mice have evolved to optimize muscle energy production, crucial for shivering to maintain body warmth in cold climates. Their mitochondria, responsible for energy conversion, exhibit higher efficiency in utilizing oxygen and nutrients, particularly lipids, for sustained energy supply during shivering.
The study also highlighted the mice’s adaptation to a limited food supply on high slopes, necessitating the consumption of potentially toxic plants. Genetic analysis revealed genetic alterations enabling the mice to detoxify harmful plant compounds, facilitating their survival in extreme environments.
The findings underscore the resilience and adaptability of life forms to challenging habitats, emphasizing the continuous surprises that evolution presents to biologists. The study sheds light on the remarkable abilities of these high-altitude mice and the underestimated potential for life to flourish in extreme conditions.