CAREER: From clock genes to phenotype: organismal response to artificial light at night

Currently, over 65% of the world’s population live under light pollution, with artificial light raising night sky luminance by over 10% of natural lighting levels. By 2025, over 80% of the world’s population will live under light polluted skies, which raises concern for human and wildlife wellbeing. This project will investigate how different colors of night lighting affect the health and behavioral rhythms of wild birds.

It will also test how night light affects avian offspring. Lastly, an integrated educational plan seeks to train the next generation of young scientists. The proposed project will: 1) provide tangible outcomes through outreach to the community, 2) provide critical information for addressing light pollution, and 3) contribute significant educational outcomes, particularly for underrepresented students.

Project results will enhance scientific and technological understanding by converting light data into the index used by light engineers, which will inform engineers about artificial light sources that are most eco-friendly. In turn, the research will benefit society by informing public policy on the biological effects of light pollution. The PI will collaborate with Philips lighting company to develop light boxes as an educational tool for elementary schools.

Additionally, the education plan contains a partnership with Sierra Nevada Journeys to develop an “ALAN (artificial light at night) and clocks” station for family STEM nights, reaching a broader audience of families, teachers, and administrators. Together, the findings of this project and the educational programs cohesively tackle an environmental pressure that is of growing societal and scientific concern.

Cycles of light are a fundamental component of natural environments, but over the last half century, electric lighting has inundated the world with ALAN. ALAN profoundly disrupts the temporal organization of light cycles, and the growing diversity of electric lights also provides light with spectra different from any natural light. It is clear from decades of research that light is the most important time cue for the regulation of circadian rhythms.

Growing evidence also suggests that light pollution causes physiological disruption and pathology. However, the molecular mechanisms that cause these downstream effects remain unclear. This project will test whether short-wavelength ALAN reduces fitness through circadian disruption.

The objectives of this proposal are to 1) evaluate whether observed physiological and behavioral effects of ALAN are due to changes in the central and peripheral clock, 2) identify effects on reproductive fitness and offspring development, and 3) engage the next generation of young scientists through educational tools and mentoring. We will combine field and laboratory experiments to test the effects of nocturnal lighting with modified spectra on behavior, physiology, reproduction, and gene expression.

By uncovering the mechanisms underlying responses to artificial light, we will be able to measure, predict and ameliorate potential harmful effects of light pollution, especially because the disruptive effects vary depending on the spectral composition of light. Merging genetic, mechanistic, and behavioral approaches is a way forward to uncover the proximate as well as ultimate consequences of light pollution.

This project is jointly funded by Integrative Ecological Physiology Program, the Behavioral Systems Cluster, and the Established Program to Stimulate Competitive Research (EPSCoR).

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.