Andy Coghlan in New Scientist:
Newborn dolphins and killer whales do not sleep for a whole month after birth, new research has revealed, and neither do their mothers, who stay awake to keep a close eye on their offspring.
The feat of wakefulness is remarkable given that rats die if forcibly denied sleep. And in humans, as any new parent will tell you, sleep deprivation is an exquisite form of torture.
The surprising sleeping patterns of captive killer whales – Orcinus orca – and bottlenose dolphins – Tursiops truncates – in the early months of life were observed by a team led by Jerome Siegel of the University of California at Los Angeles, US.
Unlike all animals previously studied, which maximise rest and sleep after birth to optimise healthy growth and development, the cetaceans actively avoided shut-eye. “The idea that sleep is essential for development of the brain and body is certainly challenged,” says Siegel.
More here.