If you’ve ever emerged from the shower or returned from your walk with a clever idea or a solution to a problem you had been struggling with, it may not be a surprise. Rather than constantly concentrating on a problem, research from the last 15 years suggests that people may be more likely to have creative breakthroughs when they’re doing a habitual task that doesn’t require much thought.

“People always get surprised when they realize they get interesting, novel ideas at unexpected times,” says Kalina Christoff, a scientist at the University of British Columbia in Vancouver, “because our culture tells us that we should do it through hard work.”

Now researchers begin to understand why these clever thoughts occur during more passive activities and what’s happening in the brain. They have found that the key is a series of brain activities—within what’s called the default mode (DM) network—that occur while an individual is resting or performing habitual tasks that don’t require much attention.

“Simply put, it is a state that your brain returns to when you’re relaxed,” explains Christoff. “By contrast, when you’re working on a demanding task, the brain’s executive control (EC) systems keep your thinking focused, analytical, and logical.”

Researchers find that the DM network is also involved in the early stages of idea generation, drawing from past experiences and knowledge about the world. When your mind wanders, you’re allowing thoughts to playfully cross your mind, which helps you combine information and ideas in new ways and something clicks.

“A cautionary note: While the DM network plays a key role in the creative process, it is the EC systems that help you to evaluate and apply the creative ideas effectively to your problems in the real world,” Christoff says. “So it’s unwise to place blind faith in the discovery that creative ideas can be generated in the shower or during any other kinds of mind wandering. Instead, you have to do the work to set the groundwork for creative ideas to emerge in the first place.”

Mountaineers have noted that as they climb, for example, up to the 12,633 foot Humphreys Peak in Arizona, plant life changes greatly. In the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless tundra (冻土带) on the top of the mountain. It may seem that plants at a given altitude are associated in what can be called “communities” — groupings of species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and are frequently to be found together. Scientists study the history of plant life and build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit caused great sheets of ice to spread from poles. These glaciers (冰川) covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to occupy, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they release pollen (花粉). Some would fall into the lake, sink to the bottom and mix with the sand. By drilling into the lake bottom it is possible to read the record of the plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual living things moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to move about — to respond to environmental changes.

Once upon a time, the family dining table would be set with a simple cloth each night. Plates, forks, and spoons would be laid out. As dinner time approached, an increasing number of hungry mouths would begin to appear with the question, “What’s for dinner?”

Now the situation is different. Where did your family eat dinner last night? In the car on the way to sports? At McDonald’s? Or at the dinner table? A survey taken a few years ago found that 28% families ate dinner together at home seven nights a week. Another quarter said they ate together three or fewer nights a week.

What accounts for this decline in families eating together today though? The data seems to point to two main issues: overworked parents and over- scheduled children. When mum or dad does get home in the evening, they are soon in the car again to send the children to soccer, music, tutoring, and a host of other events.

This nightly ceremony around the dinner table is what keeps a family together. Sure, the conversation is not always significant, and children argue. And sometimes the deepest and most meaningful times in a family are not at the table at all. However, there is still something unique about the time a family spends around the dinner table. The dinner table is the place where a family builds an identity. Stories are passed down, jokes are exchanged, and the wider world is examined through the lens (镜头) of a family’s values. Children pick up vocabulary and a sense of how a conversation is structured. Dinner time is “family time”. Coming back daily to the same place helps gain familiarity.

The significance of dinner time is more than the above. Studies show that the more families eat together, the less likely the children are to smoke, drink, and develop eating disorders, and the more likely they are to do well in school and learn how to socialize. One professor at Rutgers University in New Jersey stated, “A meal is about civilizing children. It’s a time to teach them to be a member of their culture.”

So start by planning some stay-at-home family dinners together. Just family talk.