It could be the return of “The Blob (变形怪体),” and scientists are worried. A mass of warm water extending from Baja California in Mexico all the way to Alaska and the Bering Sea could result in death for many sea lions and salmon, as well as poisonous algae (藻) blooms that can poison mussels (贻贝), crabs and other sea life. When it happened in 2014 it was known as “The Blob” and disturbed sea life between Southern California and Alaska. Now it’s back. The ocean heat wave began to form in June.

The surface temperatures in the affected areas are 5 to 7 degrees above the long-term average. The so-called blob (团)covers an area of 4 million square miles, or three times the size of Alaska. It’s 165 to 325 feet deep. The warming comes from some high pressure that keeps winds calm.

Whether it will last as long as the 2014 heat wave is impossible to know. “If the weather patterns that led to its development change all of the sudden and we get some cold weather and storms, then it could disappear pretty quickly,” said Stephanie Moore.

The heat waves are unprecedented. Satellite records go back about 40 years and ship observations 100 years, but nothing in the historical record has matched either of these two events.

Along the California coast, the blob-like warm areas are still about 1,000 miles away from shore.

In Washington state, the warm area has reached the shore, where it is causing a poisonous algae bloom that has prompted health officials to warn against eating mussels from state beaches.

Mussels have been collected on Washington shores that contained more than 10 times the regulatory limit of the toxin for human consumption. The warm area that continued to exist off the West Coast in 2014 and 2015 wasn’t something scientists had seen before.

Vampire bats live in the warmer areas of Central and South America. They are the only warm-blooded animals with a blood-only diet. They live in groups that can number from the tens to thousands of individuals.

Most people would not think of friendship and cooperation(合作)when considering vampire bats. But experts say maybe we should. New research shows that vampire bats have deeper social relationship with one another than scientists had thought. The study shows that vampire bats form friendships and meet at feeding time to hunt together.

Researchers attached small devices to 50 vampire bats in Panama to follow their path as they feed at night. The bats drink blood from wounds they cause on cows in open fields. Female bats were chosen in the study, as researchers believe they have stronger social relationships than males.

Twenty-three bats born in the wild had been caught and studied for about two years for related research into bat social behavior. Social connections had already been observed among some of them. They live together in trees, clean each other and share meals. The scientists used tiny sensor devices on the flying bats to learn whether their hunting behavior was also social. The sensor data showed that the bats would often join a “friend” while searching for food.

Gerald Carter is a scientist with the Ohio State University and the Smithsonian Tropical Research Institute. He led the research published in the journal PLOS Biology. “This study opens up an exciting new window into the social lives of these animals.” he said, “Each bat maintains its own network of close cooperative social connections.”

The researchers guess that the bats join their friends during the hunt to help each other. They think the bats might exchange information about prey(猎物)position or access to an open wound for feeding.

Simon Ripperger, a researcher at the Smithsonia Tropical Research Institute and a writer of the study said people’s first response to vampire bats is usually fear. He added, “but once you tell them about their complex social lives, they are quite surprised that we can find such behavior that is somewhat similar to what humans do-and which one would maybe expect in primates(灵长类)—in bats.”

A sleeping animal cannot look for food or flee from danger. But the fact that sleep is widespread among animals shows its restorative powers are essential. Some animals, though, try to have their cake and eat it. Dolphins and ducks sleep with half their brains, leaving the other half on guard. A paper in Science by Dr Le reports another innovative workaround. Chinstrap penguins take their sleep in thousands of naps, tiny micro- sleeps-or at least when they are nesting.

Chinstraps sleep with either their whole brain or just one half. Data confirmed they sleep in the ocean or on land. Ducks sleep in long periods, while the penguins nod of for several seconds at a time, hundreds of times an hour. The naps average 4 seconds in length; 72% lasted less than 10 seconds. Micro-sleeps aren’t unknown. Exhausted humans, like jet-lagged (倒时差) tourists and parents of newborn babies, can experience them. Totaling the duration, the researchers concluded Chinstraps get around 12 hours of sleep daily.   

Two explanations are given for Chinstraps’ sleep pattern. The first is to do with external threats. Penguins hatch eggs alone while their partners are away seeking for food. Colonies (领地) are threatened by big birds that’ll steal unattended eggs. Broken sleep is a clever strategy of getting some shut-eye during long egg-guarding periods.   

Penguins with nests near the edge of the colony are at greater risk than those in the centre, but enjoy more extended naps. The second is threats from within, as penguin colonies are noisy, crowded places. They steal nesting materials from careless neighbors, so penguins in the crime-ridden centre find it harder to sleep than those in the safer suburbs.   

Choosing between those theories requires more research. Dr Lee said, “Nor can we measure how restorative such naps are. Chinstraps are evidently able to hatch their young under such conditions, which suggests they’re getting something from their constant nodding-off. So, humans nurturing their newborns should take heart.”