Artificial Light at Night and Phenotypic Evolution
Poster Number
15B
Research or Creativity Area
Natural Sciences
Abstract
Approximately 25% of land surfaces worldwide are exposed to artificial light at night (ALAN) or ecological light pollution. Animals exposed to ALAN often exhibit disruptions to their circadian rhythms, and nocturnal animals are particularly sensitive to ALAN. However, the multi-generational (i.e., evolutionary) effects of ALAN are unknown, even though levels of ALAN globally are dramatically increasing each year. Thus, we used a laboratory natural selection experiment (a type of experimental evolution) with a nocturnal field cricket (Gryllus lineaticeps)--we exposed one population to ALAN for 14 generations while another population experienced control (dark night) conditions. In the 15th generation, we exposed some of the ALAN-selected crickets to control conditions. We then determined circadian rhythms for feeding and egg-laying, as well as important traits of life history (e.g., body size, dispersal capacity, and reproductive investment). Our experimental design allowed us to characterize whether ALAN’s effects were driven more by phenotypic plasticity (within-generation effects) relative to phenotypic evolution (across-generation effects). For example, if ALAN-induced phenotypic plasticity is important, then restoring dark night conditions for one generation may reduce disruptions to circadian rhythms brought upon by ALAN selection. Alternatively, a strong genetic (evolutionary) effect of ALAN would mean that effects of ALAN selection are more fixed and less responsive to within-generation changes to night-time light levels. Results from our experimental evolution study will be the first to quantify the evolutionary role of ALAN, which is an emerging and unprecedented feature of global environmental change.
Location
Don and Karen DeRosa University Center (DUC) Poster Hall
Start Date
27-4-2024 10:30 AM
End Date
27-4-2024 12:30 PM
Artificial Light at Night and Phenotypic Evolution
Don and Karen DeRosa University Center (DUC) Poster Hall
Approximately 25% of land surfaces worldwide are exposed to artificial light at night (ALAN) or ecological light pollution. Animals exposed to ALAN often exhibit disruptions to their circadian rhythms, and nocturnal animals are particularly sensitive to ALAN. However, the multi-generational (i.e., evolutionary) effects of ALAN are unknown, even though levels of ALAN globally are dramatically increasing each year. Thus, we used a laboratory natural selection experiment (a type of experimental evolution) with a nocturnal field cricket (Gryllus lineaticeps)--we exposed one population to ALAN for 14 generations while another population experienced control (dark night) conditions. In the 15th generation, we exposed some of the ALAN-selected crickets to control conditions. We then determined circadian rhythms for feeding and egg-laying, as well as important traits of life history (e.g., body size, dispersal capacity, and reproductive investment). Our experimental design allowed us to characterize whether ALAN’s effects were driven more by phenotypic plasticity (within-generation effects) relative to phenotypic evolution (across-generation effects). For example, if ALAN-induced phenotypic plasticity is important, then restoring dark night conditions for one generation may reduce disruptions to circadian rhythms brought upon by ALAN selection. Alternatively, a strong genetic (evolutionary) effect of ALAN would mean that effects of ALAN selection are more fixed and less responsive to within-generation changes to night-time light levels. Results from our experimental evolution study will be the first to quantify the evolutionary role of ALAN, which is an emerging and unprecedented feature of global environmental change.
