In a new paper in Trends in Ecology and Evolution, Dr Gabriel Jamie and Dr Joana Meier explore the phenomenon that the same polymorphisms often recur in many members of a species radiation (e.g. colour/pattern morphs, heterostyly, mating types, shell chirality). This phenomenon is puzzling because speciation often represents a barrier to the inheritance of the ancestral genetic variation underpinning polymorphisms. Generally, only a subset of the ancestral population go on to become founders of the new species. They outline the characteristics of polymorphisms that help their underlying genetic variation get inherited from ancestral standing variation, re-introduced through introgression or re-invented through mutation and also explore the factors influencing whether the requisite balancing selection operates widely across daughter species so that polymorphisms are maintained in many members of the radiation.
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.