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ARS Home » Southeast Area » Gainesville, Florida » Center for Medical, Agricultural and Veterinary Entomology » Imported Fire Ant and Household Insects Research » Research » Publications at this Location » Publication #333303

Research Project: Invasive Ant Biology and Control

Location: Imported Fire Ant and Household Insects Research

Title: The role of latitudinal, genetic and temperature variation in the induction of diapause of Papilio glaucus (Lepidoptera: Papilionidae)

Author
item Ryan, Sean
item Scriber, J - University Of Florida
item Valella, Patti - Michigan State University
item Thivierge, Gabrielle - University Of Notre Dame
item Aardema, Matthew - Michigan State University

Submitted to: Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/21/2017
Publication Date: 2/21/2017
Citation: Ryan, S.F., Scriber, J.M., Valella, P., Thivierge, G., Aardema, M. 2017. The role of latitudinal, genetic and temperature variation in the induction of diapause of Papilio glaucus (Lepidoptera: Papilionidae). Insect Science. doi:10.1111/1744-7917.12423.

Interpretive Summary: Understanding how insects adapt to changes in climate is critical to their conservation, management and control. A key adaptation in insects to deal with variable environmental (i.e., climatic) conditions is the ability to diapause (seasonal dormancy). Papilio glaucus and P. Canadensis are excellent models to investigate climate change and diapause, because they differ in this trait and form a hybrid zone. A scientist at the Center for Medical, Agriculture, and Veterinary Entomology, USDA-ARS, Gainesville, Florida and Scientists at the University of Notre Dame, Michigan State University, the University of Florida, Long Beach City College, the American Museum of Natural History, and Sackler Institute for Comparative Genomics, found that diapause induction occurs in the larval stage, is not sensitive to a broad range of temperatures, appears to have a complex genetic basis, and that the critical photoperiod decreases by 0.4 h with each increasing degree in latitude. This work extends our understanding of how spatial, environmental and genetic variation influences diapause induction (a key seasonal adaptation) in a well-developed ecological model system and will make possible future studies that explore how climatic variation affects the population dynamics and genetics of this system. S.R. carried out this work as part of his dissertation research before joining USDA-ARS.

Technical Abstract: A key adaptation in insects to deal with variable environmental (i.e., climatic) conditions is the ability to diapause. Papilio glaucus and P. canadensis are ideal species to explore the genetic causes and population genetic consequences of diapause because divergence in this trait is believed to be a salient factor in the maintenance of the hybrid zone between these species. Yet little is known about the factors that influence diapause induction in this system. Here we explored how spatial (latitudinal), environmental (temperature), and genetic (hybridization) factors affect diapause induction in this system. Specifically, a series of growth chamber experiments using wild caught individuals from across the eastern United States were performed to 1) evaluate how critical photoperiod varies with latitude, 2) isolate the stage in which induction occurs, 3) test whether changes in temperature affected rates of diapause induction, and 4) explore how the incidence of diapause is affected in hybrid offspring. We found that induction occurs in the larval stage, is not sensitive to a relatively broad range of temperatures, appears to have a complex genetic basis (i.e., is not simply a dominant trait following a Mendelian inheritance pattern) and that the critical photoperiod decreases by 0.4 h with each increasing degree in latitude. This work deepens our understanding of how spatial, environmental and genetic variation influences a key seasonal adaptation (diapause induction) in a well-developed ecological model system and will make possible future studies that explore how climatic variation affects the population dynamics and genetics of this system.