Skip to Main content Skip to Navigation
Journal articles

Adaptive Developmental Delay in Chagas Disease Vectors: An Evolutionary Ecology Approach

Abstract : Background: The developmental time of vector insects is important in population dynamics, evolutionary biology, epidemiology and in their responses to global climatic change. In the triatomines (Triatominae, Reduviidae), vectors of Chagas disease, evolutionary ecology concepts, which may allow for a better understanding of their biology, have not been applied. Despite delay in the molting in some individuals observed in triatomines, no effort was made to explain this variability. Methodology: We applied four methods: (1) an e-mail survey sent to 30 researchers with experience in triatomines, (2) a statistical description of the developmental time of eleven triatomine species, (3) a relationship between development time pattern and climatic inter-annual variability, (4) a mathematical optimization model of evolution of developmental delay (diapause). Principal Findings: 85.6% of responses informed on prolonged developmental times in 5th instar nymphs, with 20 species identified with remarkable developmental delays. The developmental time analysis showed some degree of bi-modal pattern of the development time of the 5th instars in nine out of eleven species but no trend between development time pattern and climatic inter-annual variability was observed. Our optimization model predicts that the developmental delays could be due to an adaptive risk-spreading diapause strategy, only if survival throughout the diapause period and the probability of random occurrence of ‘‘bad'' environmental conditions are sufficiently high. Conclusions/Significance: Developmental delay may not be a simple non-adaptive phenotypic plasticity in development time, and could be a form of adaptive diapause associated to a physiological mechanism related to the postponement of the initiation of reproduction, as an adaptation to environmental stochasticity through a spreading of risk (bet-hedging) strategy. We identify a series of parameters that can be measured in the field and laboratory to test this hypothesis. The importance of these findings is discussed in terms of global climatic change and epidemiological consequences.
Document type :
Journal articles
Complete list of metadata
Contributor : Dominique Lidoreau Connect in order to contact the contributor
Submitted on : Friday, January 7, 2011 - 2:30:16 PM
Last modification on : Tuesday, January 11, 2022 - 5:56:17 PM

Links full text




Fréderic Menu, Marine Ginoux, Etienne Rajon, Claudio Lazzari, Jorge E. Rabinovich. Adaptive Developmental Delay in Chagas Disease Vectors: An Evolutionary Ecology Approach. PLoS Neglected Tropical Diseases, Public Library of Science, 2010, 4 (5), pp.e691. ⟨10.1371/journal.pntd.0000691⟩. ⟨hal-00553488⟩



Record views