Microbial clues uncover how wild songbirds respond to stress

Every animal carries a microscopic community of bacteria, fungi, and other microbes that play a critical role in health. These gut microbes help regulate the immune system, support digestion, and even influence how animals respond to stress. In birds, stress triggers the hormone corticosterone, which helps individuals cope with challenges. But when stress is prolonged or repeated, it can disrupt the balance of microbes in the gut, potentially affecting health in ways that aren't immediately visible.