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The evolutionary history of many organisms is characterized by major changes in morphology and distribution. Specifically, alterations of body mass and geographic distribution may profoundly influence organismal life-history traits. Here, we reconstructed the evolutionary history of flight-feather molt strategy using data from 1,808 Neornithes species. Our analysis suggests that the ancestral molt strategy of first-year birds was partial or entirely absent, and that complete wing flight-feather molt in first-year birds first evolved in the late Eocene and Oligocene (25–40 Ma), at least 30 Myr after birds first evolved. Complete flight-feather molt occurred mainly at equatorial latitudes and in relatively low body mass species, following a diversification of body mass within the lineage. We conclude that both body mass and geographic distribution shaped the evolution of molt strategies and propose that the evolutionary transition towards complete juvenile molt in the Neornithes is a novel, relatively late adaptation. [ABSTRACT FROM AUTHOR]

The island syndrome describes the evolution of slow life history traits in insular environments. Animals are thought to evolve smaller clutches of larger offspring on islands in response to release from predation pressure and interspecific competition, and the resulting increases in population density and intraspecific competition. These forces become more pronounced with diminishing island size, and life histories are thus expected to become slowest on small, isolated islands. We measured clutch sizes in 12 insular populations of Mediodactylus kotschyi, a small gecko from the Cyclades Archipelago, a set of land-bridge islands in the Aegean Sea (Greece). We analyse variation in clutch size in relation to island area, island age, maternal body size, the presence of putative competitors and nesting seabirds (which increase resource abundance in the form of marine subsidies), and richness of predators. Clutch size of M. kotschyi decreases with increasing island area, in departure from classic island syndrome predictions, suggesting the evolution of faster life histories on smaller islands. There are no relationships between clutch size and island age, maternal size, the presence of competitors or predator richness. Instead, larger clutches on small islands could simply reflect the beneficial effect of marine subsidies derived from resident seabird colonies. Indeed, populations of M. kotschyi on islands with nesting seabirds have clutch sizes 30.9 % larger (1.82 vs. 1.39 eggs) than populations on islands without nesting seabirds. Thus, our data suggest that bottom-up effects of marine subsidies may supersede the expression of a simple island syndrome in the Aegean M. kotschyi. [ABSTRACT FROM AUTHOR]