Neurobiology of phenotypic plasticity in the light of climate change

Abstract Phenotypic plasticity describes the ability of an organism with a given genotype to respond to changing environmental conditions through the adaptation of the phenotype. Phenotypic plasticity is a widespread means of adaptation, allowing organisms to optimize fitness levels in changing environments. A core prerequisite for adaptive predictive plasticity is the existence of reliable cues, i.e. accurate environmental information about future selection on the expressed plastic phenotype. Furthermore, organisms need the capacity to detect and interpret such cues, relying on specific sensory signalling and neuronal cascades. Subsequent neurohormonal changes lead to the transformation of phenotype A into phenotype B. Each of these activities is critical for survival. Consequently, anything that could impair an animal’s ability to perceive important chemical information could have significant ecological ramifications. Climate change and other human stressors can act on individual or all of the components of this signalling cascade. In consequence, organisms could lose their adaptive potential, or in the worst case, even become maladapted. Therefore, it is key to understand the sensory systems, the neurobiology and the physiological adaptations that mediate organisms’ interactions with their environment. It is, thus, pivotal to predict the ecosystem-wide effects of global human forcing. This review summarizes current insights on how climate change affects phenotypic plasticity, focussing on how associated stressors change the signalling agents, the sensory systems, receptor responses and neuronal signalling cascades, thereby, impairing phenotypic adaptations.