Did you often wonder at how those tiny birds literally fly from one continent to the other? They do this twice a year migrating from a cold place to a warmer place. A new study conducted by a group of researchers Wojciechowski and colleague Berry Pinshow at Nicolaus Copernicus University in Torun, Poland revealed that the birds reduce their night time body temperatures when they stop at a place to refuel during their trips.

The birds use ‘hypothermia’ as the top strategy for their migration. The fascinating part is how these little birds deal with their environments according to their energy requirements. It is believed that humans and other warm-blooded animals experience a dip in body temperature overnight by a degree or two. While bats, rodents and chickadees can go lower than that and they do this to save energy either when the weather gets cold or when the energy supplies run low.

For this study, the researchers looked for a similar phenomenon in blackcaps that spends winters in Africa and summers in Europe. They caught 8 migrating blackcaps and implanted radio transmitters and put them in a cage. They fed them with a lot of fruits and mealworms. Their body temperatures and metabolism rates were monitored.

The study found that the birds maintained an average temperature of about 42.5 degrees Celsius during the day but at night it dropped to 39 degrees Celsius, with one bird dipping as low as 33 degrees Celsius. The study further showed that the skinniest birds cooled down the most. On the contrary, bulking up quickly helps birds get back on the road and gives them a better chance of claiming a prime spot for breeding.

Via: Discovery