title: Reduced flight-to-light behaviour of moth populations exposed to long-term urban light pollution.
abstract: The globally increasing light pollution is a well-recognized threat to ecosystems, with negative effects on human, animal and plant wellbeing. The most well-known and widely documented consequence of light pollution is the generally fatal attraction of nocturnal insects to artificial light sources. However, the evolutionary consequences are unknown. Here we report that moth populations from urban areas with high, globally relevant levels of light pollution over several decades show a significantly reduced flight-to-light behaviour compared with populations of the same species from pristine dark-sky habitats. Using a common garden setting, we reared moths from 10 different populations from early-instar larvae and experimentally compared their flight-to-light behaviour under standardized conditions. Moths from urban populations had a significant reduction in the flight-to-light behaviour compared with pristine populations. The reduced attraction to light sources of 'city moths' may directly increase these individuals' survival and reproduction. We anticipate that it comes with a reduced mobility, which negatively affects foraging as well as colonization ability. As nocturnal insects are of eminent significance as pollinators and the primary food source of many vertebrates, an evolutionary change of the flight-to-light behaviour thereby potentially cascades across species interaction networks.
authors.affiliation: Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf, Switzerland Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland florian.altermatt@eawag.ch.
authors.forename: Florian
authors.identifier: http://orcid.org/0000-0002-4831-6958
authors.initials: F
authors.lastname: Altermatt
authors.affiliation: Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland.
authors.forename: Dieter
authors.initials: D
authors.lastname: Ebert
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects*; D002947:Cities; D005260:Female; D005426:Flight, Animal / Q000528:radiation effects; D005602:France; D008027:Light; D008029:Lighting / Q000009:adverse effects; D008297:Male; D009036:Moths / Q000528:radiation effects*; D013557:Switzerland
keywords: Lepidoptera; Yponomeuta; adaptation; environmental change; natural selection