Does testosterone mediate the trade-off between nestling begging and growth in the canary (Serinus canaria)?
Nestling birds solicit food from their parents with vigorous begging displays, involving posturing, jostling and calling. In some species, such as canaries, begging is especially costly because it causes a trade off against nestling growth. Fitness costs of begging like this are predicted by evolutionary theory because they function to resolve conflicts of interest within […]
Ontogeny and symmetry of social partner choice among free-living yellow-bellied marmots
Affiliative interactions have important fitness consequences for individuals. Yet, precisely how social roles emerge across ontogeny outside of the context of agonistic interactions is largely unknown, particularly in free-living species of nonprimates. Here we used longitudinal data on yellow-bellied marmots, Marmota flaviventris, residing around the Rocky Mountain Biology Laboratory in Colorado, U.S.A., to investigate the […]