Rats and other animals need to be highly attuned to social signals from others so they can identify friends to cooperate with and enemies to avoid. To find out if this extends to non-living beings, Laleh Quinn at the University of California, San Diego, and her colleagues tested whether rats can detect social signals from robotic rats.

    They housed eight adult rats with two types of robotic rat—one social and one asocial—for four days. The robot rats were quite minimalist, resembling a chunkier version of a computer mouse with wheels to move around and colorful markings.

    During the experiment, the social robot rat followed the living rats around, played with the same toys, and opened cage doors to let trapped rats escape. Meanwhile, the asocial robot simply moved forwards and backwards and side to side.

    Next, the researchers trapped the robots in cages and gave the rats the opportunity to release them by pressing a lever.

    Across 18 trials each, the living rats were 52 percent more likely on average to set the social robot free than the asocial one. This suggests that the rats perceived the social robot as a genuine social being. They may have bonded more with the social robot because it displayed behaviours like communal exploring and playing. This could lead to the rats better remembering having freed it earlier, and wanting the robot to return the favour when they get trapped, she says.

    The readiness of the rats to befriend the social robot was surprising given its minimal design. The robot was the same size as a regular rat but resembled a simple plastic box on wheels. “We’d assumed we’d have to give it a moving head and tail, facial features, and put a scent on it to make it smell like a real rat, but that wasn’t necessary,” says Janet Wiles at the University of Queensland in Australia, who helped with the research.

    The finding shows how sensitive rats are to social cues, even when they come from basic robots. Similarly, children tend to treat robots as if they are fellow beings, even when they display only simple social signals. “We humans seem to be fascinated by robots, and it turns out other animals are, too,” says Wiles.

答案精析：本题为细节题。根据题干中的According to Quinn和the rats released the social robot可定位至原文第五段。原文中set the social robot free对应题干中的released the social robot，段末的says Quinn对应题干中的According to Quinn。该段开头说到，在18次试验中，真老鼠释放社交机械鼠的可能性比释放非社交机械鼠的可能性平均高出52%。该段后面的内容接着指出，真老鼠会释放社交机械鼠，这表明真老鼠会把机械鼠看作真正的社交个体，而这可能会让真老鼠更容易记住自己早些时候释放过它，并希望在它们自己被困时，机械鼠能反过来帮助它们来作为回报。由此可知，老鼠释放了社交机械鼠是因为它们期望机械鼠能以同样的方式予以回报，B项中的to do the same in return对应原文中的return the favour，故正确答案为B项。

错项排除：A项利用原文中的set…free和get trapped进行干扰，但原文并未提到有关“练习逃跑方法”的信息，故A项错误。C项利用原文中的displayed进行干扰，但原文说的是社交机械鼠表现出了探索和玩耍的行为，并不是说真老鼠想展示它们的智慧，故C项错误。D项利用原文中的playing进行干扰，但原文说的是社交机械鼠表现出了玩耍行为，并没有提到真老鼠认为释放机械鼠是一个有趣的游戏，故D项错误。