We all know that unpleasant feeling when we're talking about something interesting and halfway through our sentence we're interrupted. But was that really an interruption? The answer depends on whom you ask, according to new research led by Katherine Hilton from Stanford University.

Using a set of controlled audio clips (录音片段), Hilton surveyed 5,000 American English speakers to better understand what affects people's perceptions of interruptions. She had participants listen to audio clips and then answer questions about whether the speakers seemed to be friendly and engaged, listening to one another, or trying to interrupt.

Hilton found that American English speakers have different conversational styles. She identified two distinct groups: high and low intensity speakers. High intensity speakers are generally uncomfortable with moments of silence in conversation and consider talking at the same time a sign of engagement. Low intensity speakers find it rude to talk at the same time and prefer people speak one after another in conversation.

The differences in conversational styles became evident when participants listened to audio clips in which two people spoke at the same time but were agreeing with each other and stayed on topic, Hilton said. The high intensity group reported that conversations where people spoke at the same time when expressing agreement were not interruptive but engaged and friendlier than the conversations with moments of silence in between speaking turns. In contrast, the low intensity group perceived any amount of simultaneous (同时) chat as a rude interruption, regardless of what the speakers were saying.

"People care about being interrupted, and those small interruptions can have a massive effect on the overall communication," Hilton said. "Breaking apart what an interruption means is essential if we want to understand how humans interact with each other."

Wild elephants wander across the crowded flatland of India; the forested river banks through fields in Brazil; a ribbon (缎带) of green spreads across Europe where the Iron Curtain used to be. Using such wildlife corridors (走廊) to link up larger but isolated (孤立的) protected areas is the most widely used method for stopping biodiversity decline (生物多样性衰退), with millions of dollars spent creating and protecting them every year. But has enthusiasm for a neat idea got ahead of the science?

As wild habitat is broken into isolated parts by farms, roads and settlements, we need to link them up with corridors of green. Then even if the entire habitat can't be recreated, old migration (迁徙) patterns can be brought back, escape routes created ahead of climate change and — perhaps most importantly — isolated populations can interbreed (杂交), improving their genetic (基因的) diversity and their ability to survive.

Recently, Paul Beier, a biologist from Northern Arizona University, and his colleague Andrew Gregory, warned that "in spite of much research, there is little evidence that protection corridors work as expected." There is, they say, plenty of evidence that wild animals will move through corridors. But supporters of corridors want, and claim, much more than this. They say that animals don't just go for a walk in their protection woods, but that they move in forever and interbreed with neighbouring populations. In this way corridors supposedly linked isolated and endangered populations into an interbreeding — and much more powerful — whole.

Such claims sometimes hold up. In the United Kingdom, the expansion (扩张) of Kielder Forest in the 1960s provided a link between isolated populations of endangered red squirrels. Genes from isolated populations have now "spread through hundreds of forest parts" across 100 kilometers and more. But the Kielder Forest is much wider than an ordinary corridor. Few studies have looked for gene exchange in corridors; even fewer have found it. One study researched the genetic diversity of small marsupials (有袋类动物) in a narrow forest corridor crossing 4.5 kilometers of grassland in Queensland, Australia. It found that genetically distinct populations had kept on staying at either end. Mixing was impossible.

Other studies have shown that protection corridors work. But most have looked at short corridors of 100 meters through largely natural landscape. "That species can travel along short corridors in a natural setting doesn't mean that they will be successful travelling along much longer corridors which are in a landscape greatly affected by human beings," says Gregory, "still less that such movements occur frequently enough to allow enough gene exchange to occur so that the connected habitat blocks function as one population."

Perhaps we shouldn't make the perfect the enemy of the good. Is any corridor surely better than none? But consider this. The edges of wild areas are known danger zones for wildlife, where enemies and diseases may invade (侵略). Linking two existing protected areas with a long narrow corridor may uncover it to greater danger along these edges. Unless the benefit exceeds (超过) the threat, then there is serious possibility to do harm.

"Hello. You are you and I am I. We are people, also known as humans. This makes us different from most of the things on Earth." This fairly straightforward observation is the opening spread of Like, written by Annie Barrows. It establishes a somewhat odd yet matter-of-fact tone with a young boy addressing the reader.

Matters get more quizzical-or philosophical (哲学意义的), if you prefer—on the following spread, which carefully thinks about the ways in which people are different from one specific thing on Earth, "We are not at all like tin cans. We are not shaped like tin cans. We cannot hold tomato sauce like tin cans. If you open up our lids, nothing good happens. We are not at all like tin cans." The target audience will no doubt be amused, as was I, and perhaps reassured.

Like next matches people with the swimming pools, "We are a little bit more like a swimming pool than a tin can. We have water and chemicals and dirt inside us. But unlike a swimming pool we don't have people splashing around inside us." Mushrooms, we learn, differ from tin cans and swimming pools by being alive, and by growing and reproducing-human traits, too! Mushrooms, however, don't have mouths and brains. But wait: Hyenas have all that. They run around really fast, like we do... But hyenas don't say words. They don't tell stories. They don't get embarrassed, even when they're caught eating something off the ground.

Where to go from there? "Look at all these people, the text exclaims over the illustration full of people of seemingly every size, shape, color, age and means of mobility. They are not exactly like us. But they are more like us than they are different."

"I am more like you than I am like most of the things on Earth, the narrator concludes. I'm glad. I'd rather be like you than a mushroom-an appealing and inarguable understanding."