Artificial light at night disrupts gene activity and physical functions, research shows. Artificial light during darkness can have widespread effects on biological functions in animals, a study in lizards shows.Exposure to artificial light at night significantly altered gene activity in the brain, liver and skin of a common lizard.The findings show that natural cycles of light and darkness support the health of animals in wild urban habitats, and suggests that conservation efforts should be mindful of this, according to the research led by the Roslin Institute. Artificial night-time light disrupted genes across several organs in lizards. Gene disruption Groups of green anole lizards, a well-studied common reptile, were collected during midday light, darkness at midnight, or artificial light at midnight.Subsequent analysis of tissue samples compared gene activity in the brain, liver and skin across the three groups.Artificial light at night was found to affect activity in genes linked to the body’s natural 24-hour biological rhythms in all three organs.In addition, genes linked to metabolism in the liver and to wound healing in the skin were affected by light pollution.Collectively, the results indicate disruption to the body’s 24-hour circadian rhythms, as well as physiological processes. Growing evidence The study, which is the first to examine the impact of artificial light at night on several organs, aids understanding of the impact of urban light pollution on animals.It adds to findings from previous studies showing that artificial night-time light disrupts behaviours in mammals, amphibians, fish, birds and reptiles.The findings support the idea that light pollution may interfere with biological pathways across many light-sensitive species, the research team says.The research, published in Proceedings of the Royal Society B, was carried out in collaboration with Trinity University in San Antonio, US. This study builds on a growing body of evidence demonstrating the impact of light pollution on animal behaviour and physiology. Artificial light at night caused significant disruption in gene activity associated with metabolism and daily rhythms in reptiles that are commonly found in urban environments. Professor Simone Meddle Roslin Institute Collectively, these results offer further evidence that all living things benefit from natural light and dark cycles to support optimal functions. Conservation efforts should seek to mitigate light pollution as rapidly illuminated urbanised landscapes could pose a threat to the health and even survival of wild animal populations. Professor Michele Johnson Trinity University Related links Scientific publication Image credit: Professor Michelle Johnson. Tags News Roslin Publication date 13 May, 2026
