Reading: True/False - 2024 tavaszi

Penguins are champion power nappers. Over the course of a single day, they fall asleep thousands of times, each time only for a few seconds, a new study has found. Although animals have a wide range of sleeping styles, penguins easily take the record for fragmented sleeping. The science of sleep got its start in the early 1900s when researchers used scalp electrodes to discover that people produce slow brain waves when dozing. They found similar wave patterns in mice, pigeons and other captive animals. Over time, scientists discovered that every animal they studied spent some time each day unresponsive to their environment. Even jellyfish sleep despite their lack of a brain. But how animals sleep varies. Brown bats remain asleep for 20 hours a day, whereas giraffes get by on less than two hours. Seals are able to shut down a single side of their brain: with the other still awake, they can continue swimming as they doze. As technological devices have become smaller and more powerful, researchers have discovered that sleep patterns documented in animals in captivity are significantly different from those observed in the wild. In zoos, for example, sloths will sleep for almost 16 hours a day. But in a Panamanian rainforest, scientists observed the animals sleeping for less than 10. In 2019, neuroscientist Paul-Antoine Libourel and his colleagues tracked sleeping animals in a remote environment: King George Island, 70 miles north of Antarctica, where several thousands of breeding pairs of chinstrap penguins gather in nesting colonies to raise their young. They found that the birds split their time between swimming in the ocean and staying at the nests to keep their eggs and chicks warm. While in the ocean, the birds barely slept, spending just three percent of their time resting on the surface of the sea. When the penguins returned to their nests, however, their brain waves slowed to a pattern that is typical for sleeping birds — but only for a few seconds. They woke up again, only to fall back asleep. The birds sped through this cycle 600 times in an hour. Humans, too, can experience this sort of microsleep, though typically only after failing to get a good night's sleep. It can be dangerous, especially if we're nodding off at the wheel. But for chinstrap penguins, microsleep seems to be the norm.