Written by: Lisa Stelzner
Primary Source: Daily Dose of Science Blog
Bar-headed geese migrate annually between Mongolia and Tibet or India, which means they have to cross the high-elevation Himalayas. Scientists used to believe they flew at a constant, high altitude before coming down to land. However, after implanting tracking devices in migrating geese, scientists found out that they fly up and down to follow mountains’ countours closer to the ground than would seem to make sense. It turns out that if they flew at a much higher altitude, the low air density would require them to use up more energy (flap their wings more) to produce lift. There is also less oxygen that high. By flapping their wings less when they stay closer to the ground, they reduce their heart beat and save energy.
Latest posts by Lisa Stelzner (see all)
- NASA Launches Groundbreaking Soil Moisture Mapper - February 8, 2015
- Scientists dig up a new weapon against antibiotic-resistant bacteria - January 21, 2015
- Roller-coaster flight: How geese save energy while migrating - January 20, 2015