Light pollution affecting lizards’ physical functions
Artificial light affected the body's 24-hour biological rhythm.
Research has suggested that artificial light during darkness could be having a widespread effect on the biological functions of animals.
Urban lizards were found to have significantly altered gene activity in their brain, skin and liver as a result of exposure to the light.
To examine the genetic impact of different light sources, researchers examined groups of green anole lizards. These reptiles were collected during midday light, darkness at midnight and artificial light at midnight.
Tissue samples were then taken and analysed to compare gene activity in the brain, liver and skin across the three groups.
Exposure to artificial light during the night was found to affect genes involved with the body’s natural 24-hour biological rhythms in all three organs. Similarly, genes linked to metabolism in the liver and wound healing in the skin were also affected.
Researchers say that, collectively, the project proves that light pollution not only disrupts the body’s 24-hour circadian rhythm, but also its physiological processes.
The study is believed to be the first to examine the impact of artificial light at night on several organs.
It is hoped its findings will improve understanding of the impact of urban light pollution on animals, supporting previous studies into how light affects behaviours. The research team state that the findings support theories that light pollution interferes with biological pathways across many light-sensitive species.
Prof Simone Middle, of the Roslin Institute, said: “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.”
Prof Michele Johnson, from Trinity University, added: “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.”
The full study can be found in the journal Proceedings of the Royal Society B.
Image © Colombe Photographie/Shutterstock
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