Most of us start to tire after about half a day without any sleep. Staying awake for five in a row would be extremely difficult and even if you could manage it, you'd be a physical and mental wreck by the end. But not all animals suffer from the same problem. A dolphin can stay awake and alert for at least 5 days straight, chaining together all-nighters without any noticeable health problems or loss of mental agility.
The two halves of a dolphin's brain can sleep in shifts, "shutting down" one at a time so that the animal is always half-awake. They can truly sleep with one eye open, an…
bottlenose
Cuttlefish are intelligent animals that can hide from predators by changing colour and texture, and squirting out a smokescreen of black ink. But amazing though cuttlefish are, their defences mean nothing against one of the most intelligent hunters in the ocean - the bottlenose dolphin.
Julian Finn, Tom Tregenza and Mark Norman (the trio who first described the amazing mimic octopus) have discovered a single female bottlenose, who has developed a way of hunting cuttlefish. Not only does she successfully capture them, but she has learned how to prepare them for the perfect meal, with all the…
In Shark Bay, off the Western coast of Australia, a unique population of bottlenose dolphins have a unusual trick up their flippers. Some of the females have learned to use sponges in their search for food, holding them on the ends of their snouts as they rummage through the ocean floor.
To Janet Mann at Georgetown University, the sponging dolphins provided an excellent opportunity to study how wild animals use tools. Sponging is a very special case of tool use - it is unique to Shark Bay's dolphins and even there, only about one in nine individuals do it. The vast majority of them are…