Scientists have long speculated that falcons’ eye markings improve their ability to target fast-moving prey, like pigeons and doves, in bright sunlight. Dark ‘eyeliner’ feathers of peregrine falcons act as sun shields to improve the birds’ hunting ability, says a new study. It suggests that these markings have evolved according to the climate; the sunnier the bird’s habitat, the larger and darker are the tell-tale dark ‘sun-shade’ feathers.
The distinctive dark stripes directly beneath the peregrine falcon’s eyes, called the malar stripe or ‘moustache’, likely reduce sunlight glare and confer a competitive advantage during high-speed chases. It’s an evolutionary trait mimicked by some top athletes who smear dark make-up below their eyes to help them spot fast-moving balls in competitive sports.
Scientists used photos of peregrine falcons by bird watchers from around the world and scored the size of the malar stripe for each bird. They explored how these stripes varied in relation to aspects of the local climate, such as temperature, rainfall, and strength of sunlight. Results showed that malar stripes were larger and darker in regions where sunlight is stronger.
Associate Professor Arjun Amar from the UCT FitzPatrick Institute, who supervised the research, said: “The peregrine falcon represents the ideal species to explore this long-standing hypothesis, because it has one of the most widespread distributions of all bird species, being present on every continent except Antarctica – it is therefore exposed to some of the brightest and some of the dullest areas around the globe.”
Picture Credit : Google
