Climate change also affects very common species and birds. The barn owl has changed its appearance, becoming smaller and changing the color of its ventral plumage. This is demonstrated by a study of more than 5,000 specimens preserved in science museums around the world since 1900. The report was published in the Journal of Biogeography by researchers from the State University of Milan in collaboration with the University of Lausanne. The animal, present on all continents except Antarctica, was chosen as a model to study the impact of global warming on thermoregulation in endothermic species, that is to say those which maintain a constant body temperature whatever whatever the ambient temperature.
What has changed about barn owls
By analyzing specimens from 1900 to 2018, changes were detected in the length of the wings (size indicator) and the beak, the point of heat dispersion. The plumage of the ventral region (which can vary from white to dark reddish brown) has also changed. It has become lighter in areas where the climate has become hotter and drier, for better protection against the sun's rays, while it is darker where temperatures and precipitation have increased, to promote camouflage with vegetation. Body size decreased in areas most affected by global warming, while it did not change in areas where the climate remained the same. Shrinkage, explains the study, determines an increase in the ratio between the surface and volume of the body, facilitating the dispersion of heat. According to what the first author of the study, Andrea Romano, associate professor at the Department of Environmental Sciences and Policy at the University of Milan, said, barn owls could still change: “They will tend to increase in the decades to come in response to predicted global warming and that similar situations are occurring in many other species around the world.
Also read:
