Teams of mountaineering mice are helping advance understanding into how evolutionary adaptation to localized conditions can enable a single species to thrive across diverse environments. In a study led by Naim Bautista, a postdoctoral researcher in Jay Storz's lab at the University of Nebraska–Lincoln, the team took highland deer mice and their lowland cousins on a simulated ascent to 6,000 meters. The "climb" ventured from sea level and the mice reached the simulated summit seven weeks later.
Along the way, Bautista tracked how the mice responded to cold stress at progressively lower oxygen levels. Deer mice have the broadest environmental range of any North American mammal, as they are distributed from the plains of Nebraska to the summits of the highest peaks in the Rocky Mountains and Sierra Nevada. This study tested whether they are able to thrive across such a broad range of elevations by evolving adaptations to local conditions or by possessing a generalized ability to acclimatize.
" Jay Storz, Willa Cather Professor of biological sciences Conducted in a specialized lab at Canada's McMaster University, the study divided each team of highland and lowland mice into two distinct groups -; a control that remained at sea level throughout the study, and an acclimation group that embarked on the seven-week ascent. After seven days at sea-level, conditions for the acclimated group advanced by 1,000 meters in elevation weekly, with oxygen levels reduced to reflect what climber.