Nebria is a genus of flightless beetle found in montane alpine habitats, sometimes at altitudes over 3,000m. Nebria have special adaptations, such as anti-freeze enzymes, which allow them to thrive on snowy mountain tops where other insects could not. In fact, Nebria feed upon arthropod fallout, insects which are blown to high altitudes and become immobilized on the cold snow. These same cold-tolerant adaptations may prevent them from surviving at lower altitudes (Lohse et al. 2011). As a result, their mountain top homes act like isolated “sky islands.’ Dispersing between sky islands is challenging when you can’t fly. Continue reading “Lonely at the Top: isolated mountain tops served as ice age refugia”