Lower Deciduous (IMAGE) Princeton University Caption A Princeton University-based study suggests that the ranges of birds in the world's temperate mountain areas may actually be determined more by temperature and habitat than competition, as is often presumed. The study focused on three types of mountain habitat similar to those found in other temperate regions, including the United States: mixed broad-leaf and coniferous forests (above center); mixed coniferous forests; and high-altitude forests composed largely of hardy evergreens such as firs. Species such as the grey-winged blackbird (Turdus boulboul) (left) and the snowy-browed flycatcher (Ficedula hyperythra) (right) live side-by-side with competitors. Credit (Photos by Prashant Negi and Paul Elsen, Department of Ecology and Evolutionary Biology) Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.