Divergent adaptations in resource-use traits explain how pikas thrive on the roof of the world

Life in extreme environments is possible through multilevel adaptations to physical and biotic stresses. At high elevations, species face numerous challenges, besides low oxygen levels, but previous studies have focused on genetic and physiological adaptations to chronic hypoxia while overlooking other key strategies for thriving in alpine landscapes.
Here, we investigate resource-use trait adaptations to extreme elevations using pikas as a model, lagomorphs distributed up to 6200 metres and reaching maximum diversity on the Qinghai-Tibet plateau, the highest plateau on Earth. Specifically, we assess cranial evolution in pikas using geometric morphometric and phylogenetic comparative techniques to determine whether adaptations among high-elevation biota shown at the molecular and physiological levels also occur in resource-use traits. We further explore the roles of two contrasting lifestyles (burrowing and rocky-dwelling) in cranial evolution.
We found that alpine species exhibit strik...