ArticleThe Journal of experimental biology2021
Exposure to artificial light at night alters innate immune response in wild great tit nestlings.
Article in The Journal of experimental biology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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Who cites it
15 citing papers in PubMed, 1 synthesis or guideline pooled it, 45 citations in OpenAlex.
- Artificial Light at Night Consistently Impacts Avian Physiology and Behaviour: A Meta-Analysis.Ecology letters · 2026Pooled it
- Dietary melatonin supplementation mitigates the negative effects of artificial light at night in the Pacific field cricket,Proceedings. Biological sciences · 2025Article
- Artificial light at night (ALAN) negatively affects nest site occupancy but does not influence breeding success in two sympatric owl species.Scientific reports · 2025Article
- Artificial light at night weakens body condition but does not negatively affect physiological markers of health in great tits.The Journal of experimental biology · 2025Article
- Eye catching light: Anthropogenic light at night and its evolutionary influence on the avian eye.iScience · 2025Article
- Avian circadian clock genes: ontogeny and role for adaptive programming in avian embryos.Frontiers in physiology · 2025Review
- Endocrine-circadian interactions in birds: implications when nights are no longer dark.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2024Review
- Molecular mechanisms of artificial light at night affecting circadian rhythm disturbance.Archives of toxicology · 2024Review
- Artificial light at night reduces earthworm activity but increases growth of invasive ragweed.BMC ecology and evolution · 2024Article
- Experimental light at night explains differences in activity onset between urban and forest great tits.Biology letters · 2023Article
- Interactive effects of rising temperatures and urbanisation on birds across different climate zones: A mechanistic perspective.Global change biology · 2023Review
- Innate immune function and antioxidant capacity of nestlings of an African raptor covary with the level of urbanisation around breeding territories.The Journal of animal ecology · 2023Article
- Effects of light pollution on photoperiod-driven seasonality.Hormones and behavior · 2022Review
- Light at night disrupts biological clocks, calendars, and immune function.Seminars in immunopathology · 2022Review
- Exposure to artificial light at night alters innate immune response in wild great tit nestlings.The Journal of experimental biology · 2021Article
Corrections and comments
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Authors and funding
7 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The large-scale impact of urbanization on wildlife is rather well documented; however, the mechanisms underlying the effects of urban environments on animal physiology and behaviour are still poorly understood. Here, we focused on one major urban pollutant - artificial light at night (ALAN) - and its effects on the capacity to mount an innate immune response in wild great tit (Parus major) nestlings. Exposure to ALAN alters circadian rhythms of physiological processes, by disrupting the nocturnal production of the hormone melatonin. Nestlings were exposed to a light source emitting 3 lx for seven consecutive nights. Subsequently, nestlings were immune challenged with a lipopolysaccharide injection, and we measured haptoglobin and nitric oxide levels pre- and post-injection. Both haptoglobin and nitric oxide are important markers for innate immune function. We found that ALAN exposure altered the innate immune response, with nestlings exposed to ALAN having lower haptoglobin and higher nitric oxide levels after the immune challenge compared with dark-night nestlings. Unexpectedly, nitric oxide levels were overall lower after the immune challenge than before. These effects were probably mediated by melatonin, as ALAN-treated birds had on average 49% lower melatonin levels than the dark-night birds. ALAN exposure did not have any clear effects on nestling growth. This study provides a potential physiological mechanism underlying the documented differences in immune function between urban and rural birds observed in other studies. Moreover, it gives evidence that ALAN exposure affects nestling physiology, potentially causing long-term effects on physiology and behaviour, which ultimately can affect their fitness.
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