Tanmay Dixit has commenced his PhD research on egg mimicry in the Cuckoo Finch and egg rejection behaviour by their hosts (family Cisticolidae). He plans to use approaches from applied mathematics, visual ecology and psychology to understand how hosts recognise eggs, and the implications for this on host egg phenotypes and parasite mimicry. This Cuckoo Finch chick, held by Tanmay above, was clearly a successful mimic!
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.