Why do migratory birds sing on their non-breeding grounds in Africa during the northern winter? It’s long been assumed that they are defending individual non-breeding territories, but by means of field experiments and radio-tracking of Willow Warblers in the field in Zambia, PhD student Marjorie Sorensen shows that the winter lives of Palaearctic-African migrants can be much more social and intriguing: read the full paper in Behavioral Ecology.
Our paper ‘Why and how to apply Weber’s Law to coevolution and mimicry’ has been published in the journal Evolution. This perspectives paper, written by Tanmay Dixit, Eleanor Caves, Claire Spottiswoode, and Nicholas Horrocks, argues that Weber’s Law of proportional processing can lead to otherwise counterintuitive predictions about the evolutionary trajectories of mimicry systems. Weber’s Law states that when the magnitude of a stimulus is large, it is more difficult to discriminate a change or difference from that stimulus. In other words, relative differences are more salient than absolute differences. We show that Weber’s Law could have implications for mimicry: when stimulus magnitudes are high, it should be more difficult to discriminate a model from a mimic. This leads to testable predictions about evolutionary trajectories of models and mimics. We also present a framework for testing Weber’s Law and its implications for coevolution.