image: Cavity-nesting birds, like this mountain chickadee about to feed its young, have safer nests that allow young to stay in nests longer and develop their wings for improved flight at leaving. This material relates to a paper that appeared in the 20 June 2018, issue of Science Advances, published by AAAS. The paper, by T.E. Martin at U.S. Geological Survey in Missoula, Mont., and colleagues was titled, "Age and performance at fledging is a cause and consequence of juvenile mortality between life stages." view more
Credit: [Credit: T. E. Martin]