Vibrissal sensing in mammals in a changing world.

Mammalian vibrissae are part of a specialised, sensitive and precise sensory system. They are involved in multimodal reception, including vibrotactile and electric sensing, which might make them particularly prone to multiple perceptual elements of environmental change. This Review considers the important implications of environmental change for vibrissal form, behaviour and neural signalling. Findings reveal that environmental change can impact all modalities of vibrissal sensing. Increasing exposure to new plant species, pathogens and chemicals in the environment impacts vibrissal growth, sensitivity and neural processing. Acoustic noise and altered air and water flow regimes will cause vibrissal shaft oscillations and may even have the capacity to mask critical stimuli, such as prey signals, although this has not yet been studied. Despite evidence of vibrissal sensing being robust to environmental change in some contexts, such as being able to regulate warm temperatures, many environmental impacts remain poorly understood. There is a need to better understand the levels of pollution and noise in the environment and incorporate these as relevant environmental stimuli in experiments to investigate their impact on vibrissal sensing. Adopting a broader taxonomic focus would also give greater insight into species-specific vibrissal adaptations, many of which can be seen in this Review in response to dietary adaptations. Adopting these approaches in future studies will enhance our understanding of the resilience and vulnerability of vibrissal sensing in the face of rapid environmental change.