In a new paper in Ostrich: Journal of African Ornithology, Dr Gabriel Jamie, Dr Samuel Jones, Emidio Sumbane and Merlijn Jocque present the results of a three-week expedition to three poorly-known mountains in northern Mozambique: the Njesi Plateau, Mount Chitagal and Mount Sanga. These mountains had received little to no previous biological surveys, but are the only known locality of the endangered Mozambique Forest-warbler Artisornis sousae (formerly Long-billed Tailorbird A. moreaui sousae). During the survey, the authors found healthy populations of the tailorbirds on all three mountains along with two new species for Mozambique. They also recorded several range extensions of both conservation and biogeographical importance including a new population of the highly localised Dapple-throat (Aracanator orostruthus). Overall, they find that the birdlife of the Njesi highlands are more biogeographically linked to Tanzania, than to mountains farther south in Mozambique and Malawi. Their results illustrate the critical value of even small Afromontane forests on remote highlands for some of Africa’s least known, and most threatened avifauna.
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.