题目内容：

Oh, the places you’ll go!

When it comes to habitat, human beings are creatures of habit. It has been known for a long time that, whether his habitat is a village, a city or, for real globe-trotters (周游世界者), the planet itself, an individual person generally visits the same places regularly. The details, though, have been surprisingly obscure. Now, thanks to an analysis of data collected from 40,000 smartphone users around the world, a new property of humanity’s locomotive (移动的) habits has been revealed.

It turns out that someone’s “location capacity”, the number of places which he or she visits regularly, remains constant over periods of months and years. What constitutes a “place” depends on what distance between two places makes them separate. But analyzing movement patterns helps illuminate the distinction and the researchers found that the average location capacity was 25. If a new location does make its way into the set of places an individual tends to visit, an old one drops out in response. People do not, in other words, gather places like collector cards. Rather, they cycle through them. Their geographical behavior is limited and predictable, not fancy-free.

The study demonstrating this, just published in Nature Human Behavior, does not offer any explanation for the limited location capacity it measures. But a statistical analysis carried out by the authors shows that it cannot be explained solely by constraints on time. Some other factor is at work. One of the researchers draws an analogy. He suggests that people’s cognitive capacity limits the number of places they can visit routinely, just as it limits the number of other people an individual can routinely socialize with. That socialization figure, about 150 for most people, is known as the Dunbar number, after its discoverer, Robin Dunbar.

Lehmann says his group is now in search of similar data from other primates (灵长目动物), in an attempt to work out where human patterns of mobility have their roots. For those, though, they will have to rely on old-fashioned methods of zoological observation unless they can work out a way to get chimpanzees to carry smartphones.

1.The underlined word “obscure” in paragraph 1 can be replaced by     .

A. clear    B. little known

C. accurate    D. long forgotten

2.How can the researchers get similar data from other primates?

A. Observe the primates or let them carry smartphones.

B. Work together with Robin Dunbar.

C. Carry out statistical analysis.

D. Publish essays in Nature Human Behavior.