The evolution of sensitive periods in development: insights from insects

Abstract

Recent models have identified evolutionary explanations for sensitive periods, when individuals are more responsive to experiences at certain stages of development, based on benefits and costs of attending to environmental cues. Empirical tests of these models face challenges, requiring complex, long-term experiments, and detailed understanding of physiology and ecology. Insect systems offer the opportunity to overcome these challenges, given their tractability, diversity and well-studied mechanisms. These studies shed light not only on fundamental biology, but have societal implications given the roles insects play in pollinating or decimating food crops and in spreading parasites. Understanding the role of sensitive periods can help to protect beneficial insect populations while controlling pests and vectors of disease.

Sensitive periods, but not critical periods, evolve in a fluctuating environment: a model of incremental development

“…The extent to which these patterns depend on the rate of environmental change, the reliability of cues or the duration of adulthood relative to ontogeny remain to be explored. Experimental evolution studies of bulb mites and other insect species can be used to explore different parameter combinations and test predictions from models like ours [40].…”

Early Life Exposure to Queen Mandibular Pheromone Mediates Persistent Transcriptional Changes in the Brain of Honey bee Foragers

“…1), suggesting that the time window for large-scale QMP effects closes very early in the life of a worker bee. ( Sensitive periods exist across the animal kingdom and are generally characterized by a limited duration for key developmental processes in response to external cues or stimuli (44,82,83). An individual's response to the cues or stimuli from the external environment is variable but the interaction can influence subsequent physiology and behavior.…”

Intergenerational Effects of Early Life Starvation on Life-History, Consumption, and Transcriptome of a Holometabolous Insect

“…Intergenerational effects of starvation events on offspring developmental trajectories have been found to differ depending on the exact starvation regime, sex, and traits that are considered (Saastamoinen et al 2013; McCue et al 2017; Paul et al 2019). Moreover, to fully elucidate the adaptive nature of intergenerational effects, studies should encompass different phases in development during the parental life cycle and how such experience affects individual offspring phenotypes (English and Barreaux 2020).…”

“…Periods of starvation are commonly encountered by insects in the wild (Jiang et al 2019) and, when experienced early in life, often have long-lasting consequences on an individual's phenotype (Miyatake 2001;Wang et al 2016;McCue et al 2017) and the phenotype of the offspring (Saastamoinen et al 2013;McCue et al 2017;Paul et al 2019). However, it is also becoming increasingly apparent that to fully elucidate the adaptive nature of intergenerational effects, studies should encompass different phases in development of the parental life cycle and how such life stage-specific experience affects offspring phenotype (English and Barreaux 2020).…”

“…With discrete phases during development, insects, particularly holometabolous insects, present ideal organisms in which to investigate how environmental cues experienced during early life but also during adulthood (e.g. mating) may interact with offspring environment, to influence individual offspring phenotypes (English and Barreaux 2020). Periods of larval starvation are known to influence developmental trajectories with knock-on effects on adult size, reproductive success and adult starvation resistance (Boggs and Niitepõld 2016;Wang et al 2016).…”