Community modeling reveals the importance of elevation and land cover in shaping migratory bird abundance in the Andes.

The tropical Andes are characterized by extreme topographic and climatic complexity, which has likely contributed to their outstanding current species diversity, composed of many range-restricted species. However, little is known about how the distribution and abundance of highly mobile organisms, like long-distance migratory birds, varies across different land covers, elevations, and climatic conditions within the Andes. We conducted 1,606 distance-sampling point counts across the Colombian Andes, spanning elevations from 253 to 3,708 m, a range of precipitation regimes and representative land covers.

Digest: Selection for staggered pollen release as a driver of heteranthery.

Why do some flowers have stamens of different shapes and sizes? Focusing on a group of Neotropical flowering plants, Dellinger et al. tackled this question and found that the evolution of heteranthery, contrary to the predominant view, is not strictly related to pollen-reward pollination and selection for division of labor between stamens. Moreover, they found support for the idea that selection for staggered pollen release might lead to heteranthery.