A recent genetic discovery has revealed that the pale grey plumage of the tawny owl is linked to crucial functions that aid the bird’s survival in cold environments. As global temperatures rise, dark brown plumage is likely to become more common in tawny owls living in colder areas.
Coloration is an intriguing biological trait in animals and plants that has always fascinated biologists. Evolution has shaped the variety of colors to aid in a range of natural interactions. Coloration can help animals blend into their surroundings to avoid predators or attract a mate. It can also be linked to physiological properties conferred by pigments.
The tawny owl is a nocturnal bird of prey that inhabits woodlands across Europe and western Siberia. Their color ranges between pale grey and darker brown. The coexistence of both color morphs is believed to be due to their adaptations to the surrounding environment. Darker individuals are more consistently found in warmer and humid environments, whereas pale-grey individuals are more frequently observed in cold, dry, and snow-prone environments, such as northern Europe.
“Based on this assumption, it has been predicted that the warming climate and snow scarcity may lead to a shift towards darker feather colouration in cold regions that have been dominated by grey owls,” says Postdoctoral Researcher Miguel Baltazar-Soares, who led an international team composed by researchers from the University of Turku in Finland, and the University of Lund and the University of Linköping in Sweden.
In a recent study, researchers sequenced the entire genome of the tawny owl for the first time and screened the genome of 370 tawny owl specimens. The study aimed to find links between feather color polymorphism and adaptation to different environments. The researchers discovered that certain gene variants are associated with color polymorphism and may be involved in biological functions that are crucial for the owl’s survival in extreme weather conditions. These functions include energy homeostasis, fat deposition, and control of starvation responses, which indicate adaptations to local environmental conditions. The study found that the combinations of two genetic variants can predict grey coloration in owls with an accuracy of 70% to 100%. The researchers suggested that these co-occurring color morphs may be an adaptive response to climate conditions. However, the functionality of these genetic variants will need to be further verified in future studies.
