Almost all new parents struggle to get enough sleep while caring for their newborns. For some penguin (企鹅) parents, though, periods of sleep are especially short.

Researchers recently found that Chinstrap penguins only sleep for about four seconds at a time in order to protect their eggs and newborn chicks. They do this thousands of times throughout the day. The short "microsleeps" total around 11 hours each day. The microsleeps appear to be enough to keep the parents going for many weeks.

Niels Rattenborg, a sleep researcher at the Max Planck Institute for Biological Intelligence in Germany, said, "What's surprising is that the penguins are able to function okay and successfully raise their young."

Chinstrap penguins usually lay their eggs in November in nests made up of small rocks. Mated (交配的) pairs share parenting responsibilities. One parent usually watches the eggs and chicks alone while the other goes off fishing for family meals. Adult penguins don't face many natural enemies in the mating season. But large birds called brown skuas eat the penguin eggs and small chicks. Other adult penguins may also try to steal the small rocks from the nests, so penguin parents must always be on guard.

For the first time, scientists followed the sleeping behavior of Chinstrap penguins. They did this by attaching devices that measure brain waves. They collected data on 14 adults over 11 days on King George Island off the coast of Antarctica.

Won Young Lee, a biologist at the Korean Polar Research Institute, thought of the idea for the study when he saw mating penguins often blinking (眨) their eyes and possibly sleeping. But the team needed to record brain waves to confirm the animals were sleeping. "For these penguins, microsleeps have some restorative functions," he said. He added that they would not survive without it.

The researchers didn't collect sleep data outside the mating season. But they suspect that the penguins may sleep for longer periods at other times of the year.

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The world's only captive (圈养) brown giant panda, Qizai, has been taking more exercise in preparation for the upcoming breeding (繁育) season. He is encouraged to stand up by keepers who place food on the end of a stick held just out of his reach. Panda experts believe that strengthening the giant animal's legs will improve his ability to breed successfully.

The world's first brown panda was discovered in 1985 in the Qinling Mountains. All photographs of wild brown pandas were taken in the area, which they were named after. The Qinling giant panda, first recognized in 2005, is a subspecies of giant panda. As well as its brown and white fur, it has a smaller and rounder skull and a shorter nose than the more familiar Sichuan giant panda.

Qizai, whose name means the seventh son, was found as two-month-old cub, weak and alone, by researchers in a nature reserve in the Qinling Mountains. For his safety, the researchers took him to the nearby Shanxi Rare Wildlife Rescue Centre where he was given medical treatment and fed on milk from other pandas.

There are 1, 864 giant pandas in the wild, according to World Wildlife. They live mainly in bamboo forests high in the mountains of south-west China, mostly in Sichuan province, but they can also be found in Shanxi province, where Qizai is from. He was previously thought to be the only living brown panda in the world until a wild panda with the same colour pattern was spotted roaming in a nature reserve in Shanxi in March, 2018. Up to now spotting brown pandas in the wild has taken place no more than ten times, all of which were in the central Qinling Mountains.