Dolphins have developed a unique ability to sleep using only half their brains, allowing them to fend off predators for at least 15 consecutive days, a new study has found.
A team of researchers led by the National Marine Mammal Foundation discovered that dolphins use echolocation - a process that involves using echoes to locate and identify objects - with near-perfect accuracy for days on end.
The study suggests that the adaptation serves a dual purpose. In addition to helping fend off sharks, a prolonged state of vigilance also prevents the dolphins from drowning.
The findings have been published online in the peer-reviewed journal PLOS One.