Now that we’re done with the behavioral indicators, let’s check out the physical signs of aging in birds. Changing beak color In some species of birds, the beak starts to change color as the bird ages. Eclectus parrots, for instance, have orange beaks that turn yellow as they grow old...
Infectious diseases are one of the most common threats for both domestic and wild animals, but little is known about the effects on the physiological condition and survival of wild animals. Here, we have tested for the first time in a wild vertebrate facing a viral disease possibly due to he...