Compared to dogs, cats are often considered to be cold to their human owners. It is usual for them to be indifferent（无动于衷的）when humans call their names. Are we sure that they don't understand human voices at all?

A recent study published in the journal of Scientific Reports suggests that we've been fooled. Japanese scientists found that cats can recognize their names if their owners regularly use them. In the study, scientists recruited (招募) 78 domestic cats. They played recordings of voices of their owners saying five words: the first four words were random nouns that resembled their names while the final word was the cat's name. Then they observed the cats' responses, if there were any.

Most of cats moved their ears or heads when they heard their names, while they made no response to other words. That suggested, "cats were paying attention to you, what you say and what you do," John Bradshaw, an expert on human-animal interactions at the University of Bristol, UK, told The Times. "And cats were just as good as dogs at learning," she added.

In the study, when people called their names, cats often associated (联系) the words with rewards, such as food or play, or with"punishments" such as having a bath or going to the vet. This made cats sensitive（敏感的）to words. After the cats had been called several times, they could respond to the words. But the scientists added that while dogs have evolved（进化）to follow their owners' orders, cats have not. Although cats appear to be distant, they do have special relationships with their owners.

According to study co-author Atsuko Saito, cats have evolved not to show their emotions as a survival method. One example is illness, which they tend to hide because “in the wild, no one can rescue them" and predators（捕食性动物）are more likely to pay attention to them, ” Saito explained.

However, technology may help bridge the communication gap between cats and us. There are now mobile apps available to explain what their meows mean. So, the next time you hear "meow, meow", your cat may be telling you, "Hi, you haven't cleaned my litter box recently."

Neanderthals were close relatives of modern day humans. The first Neanderthal remains were found in 1856 in the Neander Valley in Germany, which is where the name comes from. Neanderthals died out about 40,000 years ago, so there’s a lot that we still don’t know about them.

Until recently, many scientists believed that Neanderthals weren’t very smart. But recent discoveries have suggested that Neandelhals developed skills far more advanced than people used to believe.

For example, Neanderthals knew how to make a kind of glue from a birch tree. The method for making this glue isn’t simple.

Now, scientists report that they’ve found a tiny piece of string(线)on a stone tool made by Neanderthals about 50,000 years ago. Before this, the oldest piece of string was made by humans about 19,000 years ago.

On the side of the tool, researchers found a bit of string about 0.55 millimeters long. Almost all things made from plants during the time of the Neanderthals have broken down and disappeared, so it’s very special to find this bit of string.

The scientists don’t know if the string was attached to the tool or if the two were pressed together over time. But that doesn’t interest them as much as the fact that Neanderthals knew how to make string.

Making string is a complicated process. Bruce Hardy, the lead scientist on the project, says that knowing how to make string was important technology for humans. “We wouldn’t really be here today, where we are in the world, without twisted fibers (捻制的纤维品),” he said. So learning that Neanderthals also knew how to make string is an important discovery.

The scientists aren’t sure what the string was used for, but they say that string like the bit that was found could be used to make bags, mats, nets, cloth, baskets, traps, or other things.

A water-proof drone (无人机) is used by Australian scientists to collect the highly-treasured nasal mucus (鼻部黏液) of migrating whales which is rich in fresh DNA viruses and bacteria. It flies over the blowholes of humpback whales as they go on their annual journey along Australia’s east coast.

Vanessa Pirotta, a biologist at Macquarie University, says that nasal mucus indicates the health of the whale “It’s the juicy biological mixture you see as a whale surfaces from the water to take a breath,” she said. “You often see that mist and hear the sharp breaths as a whale breathes because after all, they are mammals like us and have two nostrils (鼻孔). As they take a breath a lot of lung bacteria come out from their lungs, which we can collect to provide a picture of whale health.”

Australian researchers have attached a petri dish (培养皿) that is used in scientific tests to a drone which flies through the whale’s nasal mist.

Vanessa Pirotta says, “As a whale surfaces to take a breath — you can actually see it on good weather days — the drone lowers, the petri dish is then opened and the drone is flown through the thickest part of the whale snot (鼻涕), collecting the sample in the petri dish. Now once this happens the lid is shut and the drone is flown back to the research ship and we collect the sample to later process it in the laboratory.”

The research could help to solve one of the mysteries of another wonderful creature of the deep-the Southern right whale. Its numbers have recovered on Australia’s west coast since hunting was illegalized but its population on the eastern seaboard remains stubbornly low.

In the past, studies into whale health had to rely on examining whales that were either killed or grounded on a beach. Now drones allow scientists to collect samples from free-swimming whales to gather information without harming them.