Recordings (录音) of angry bees are enough to send big, tough African elephants running away, a new study says. Beehives ( 蜂窝) either recorded or real may even prevent elephants from damaging farmer’s crops.

Years ago, scientist Lucy King and her team found that elephants avoid certain trees with bees living in them. Today, Lucy wants to see if African honeybees might stop elephants from eating crops.

But before she asked farmers to set up beehives on their farms, she needed to find out if the bees would frighten elephants away.

Lucy found a wild beehive inside a tree in northern Kenya and set up a recorder. Then she threw a stone into the beehive, which burst into life. Lucy and her assistant hid in their car until the angry bees had calmed down. Next, Lucy searched out elephant families in Samburu National Reserve in northern Kenya and put a speaker in a tree close to each family.

From a distance, Lucy turned on the pre-recorded sound of angry bees while at the same time recording the elephants with a video camera. Half the elephant groups left the area within ten seconds. Out of a total of 17 groups, only one group didn’t react to the sound of the angry bees. Lucy reported that all the young elephants immediately ran to their mothers to hide under them. When Lucy played the sound of a waterfall ( 瀑布) instead of the angry bees to many of the same elephant families, the animals were undisturbed. Even after four minutes, most of the groups stayed in one place.

Lucy is now studying whether the elephants will continue to avoid the sound of angry bees after hearing it several times. She hasn’t tested enough groups yet to know and she has now begun placing speakers in the fields to see if elephants are frightened away.

“We thought dogs would behave like children under age 5, but now we guess that perhaps dogs can understand when someone is dishonest,” says Huber at the University of Vienna in Austria. “Maybe they think, ‘This person has the same knowledge as me, but is giving me the wrong information.’ It’s possible they could see that as intentionally misleading, which is lying.”

Once that trust was established, the team had the dogs witness another person move the food from the first to the second bowl. The communicators were either in the room, and also witnessed the switch, or were briefly absent and so apparently unaware that the food had been switched. In either case, the communicators would later recommend the first bowl, which was now empty.

In previous versions of this experiment with children under age 5, the participants reacted in particular ways. They would typically ignore the communicator who gave honest but misleading advice on where the food was. However, if the communicator had been in the room and witnessed the switch, but still recommended the first (now empty) bowl, young children were actually much more likely to follow the communicator’s knowingly misleading suggestion.

This may be because the children and non-human primates (灵长类) trusted the communicator over the evidence of their own eyes, says Huber.

The dogs in the new experiment, however, weren’t so trusting of lying communicators, much to the researchers’ surprise, says Huber. Half of the dogs would follow the communicator’s misleading advice if the communicator hadn’t witnessed the food switch. But about two-thirds of dogs ignored the communicator who had witnessed the food switch and still recommended the now-empty bowl. These dogs simply went to the bowl filled with food instead. “They did not rely on the communicator anymore,” says Huber.

New research on ants has firstly shown that insects have the ability to shrink and then regrow their brains. It relates to how these particular ants, called the Indian jumping ant, reproduce.

“In most ant colonies (种群), the queen is the only member of the colony that lays eggs. When she dies, the colony dies. The workers just do the hunting and take care of the babies and the chores.” says Clint Penick, a professor of biology at Kennesaw State University in Georgia. But this is not true for Indian jumping ants. Their worker ants have the ability to mate and reproduce. So when the queen dies, a dominance tournament starts. They’ll fight each other over a month to decide who’s going to be the next queen.

The queen doesn’t have an exact replacement. Tournament winners — called “gamergates” — all assume queen-like duties of laying eggs. The study found that when the ants take on the role of gamergates, their brains reduce its size by 19% on average, so that they can save energy to focus on producing eggs. The fact that the ants’ brains shrink to reproduce wasn’t new. But what scientists didn’t know was whether they had the ability to regrow.

Penick’s team separated gamergates from their colonies for a few weeks. The thinking was that the lack of social interaction and care would make them return to their previous status. It worked. After several weeks, the ex-gamergates were back to being low-class workers — with their bigger brains regrown. “We are now starting to find that there are animal species that are capable of shrinking their brains and then regrowing them, even humans to some degree.” Penick says.

There are still potential suggestions for humans. According to Penick, the brains are more flexible in size than we knew. The brains of ants have some shared features with humans. So now scientists are looking at digging into the genetic and other neural mechanisms (神经机制) supporting these brain changes.