Mechanisms regulating phenotypic plasticity in wing polyphenic insects

Abstract

Abstract Wing polyphenisms are found in a diversity of insect species. These insects are characterized by their ability to produce multiple, discrete, alternate morphologies based on environmental signals received during development from a single genotype. Individuals within a species that exhibit wing polyphenism have varying degrees of flight capability based on their wing morphology. This classic example of a life history trade-off between migration (the winged morph) and reproduction (the short-winged morph) is predicated on the prediction that the long wing form is at a reproductive disadvantage compared to the short wing form. Many species of aphids, brown planthoppers, and crickets exhibit this remarkable ability to assess environmental cues before producing either a long wing, small ovary female or a short wing, large ovary female. Data from studies of environmental factors such as nutrition, density, injury, photoperiod, temperature, interactions with other species, and pesticides are discussed. A comprehensive review of endocrine and cell signalling evidence is synthesized and compared. The goal of this review is to synthesize the environmental, endocrine, and cell signalling information on these insects to determine what the next steps are for research in this area. Developmental phenotypic plasticity is vital for the success of a species and we explore the mechanisms for how species respond to environmental stimuli from the gene to the phenotype.