Kids everywhere love to play. And they know that a ball is a perfect thing to play with. Now scientists report bumblebees(大黄蜂)seem to know the same thing, making bumblebees the first insects known to play.

Lots of animals play. But the behavior is best known in mammals(哺乳动物)and birds. For many animals, playing is often seen as a kind of training for things they’ll have to deal with in later life.   But before this, there were no reports of insects playing.

Dr. Lars Chittka did an earlier experiment, where he trained bumblebees to roll balls into a goal for food. He noticed some bees were rolling balls even when they weren’t rewarded. He wondered if they were playing.

To test the idea，he with other scientists set up a new experiment. First, they marked 45 young bumblebees, both male and female, between one and 23 days old. Then they set up a clear pathway from the bumblebees’ nest to a feeding area. On either side of the open pathway, small colored wooden balls were placed. On one side of the path，the balls couldn’t move. On the other side, the balls could roll around.

For three hours a day over 14 days, the scientists opened the pathway. The bumblebees never had to leave the pathway to find food, but they left anyway. They weren’t so interested in the side where the balls couldn’t move, but they made lots of visits to the side with the rolling balls.

Grabbing the balls with their legs, the bumblebees would beat their wings to pull on the balls, causing them to roll. The 45 marked bumblebees did this 910 times during the experiment. Though some only did it once, others did it a lot. The scientists found the younger bumblebees spent more time rolling balls, and that males seemed more likely to play than females.

The scientists say it’s not clear why the bumblebees roll the balls or whether they enjoy it. But the experiment raises important questions about how the insects’ minds work and whether they have feelings.

According to a paper in Psychological Science, how you represent yourself in the virtual world may affect how you behave towards others in the real world. The authors wondered whether virtual experiences—specifically, the experiences of taking on heroic or villainous (反派的) avatars—might carry over into everyday behavior. “Our results show that just five minutes of role-play in virtual environments as either a hero or a villain can easily cause people to reward(回报) or punish strangers,” says author Gunwoo Yoon.

The researchers had 194 college students take part in two different studies. In the first study, the participants were asked to play as Superman (a heroic avatar) or Voldemort (a villainous avatar). They played a game for 5 minutes in which they, as their avatars, were tasked with fighting enemies. Then, in the other study, they took part in a blind taste test. They were asked to taste chocolate or chili sauce (辣椒酱) and then it’s up to them to decide whether to give the next participant chocolate or chili sauce. They were told that the next participant would eat all of the food provided.

Participants who had played as Superman poured, on average, nearly twice as much chocolate as chili sauce for the next participant. And they poured much more chocolate than those who played as Voldemort. Participants who played as Voldemort poured nearly twice as much chili sauce as chocolate, and they poured much more chili sauce compared to those who played as Superman.

A second experiment with 125 college students reported the same findings and showed that actually playing as an avatar had stronger effects on the following behavior than just watching someone else play as the avatar. “In virtual environments, we can freely choose avatars that allow us to get into a certain group,” says Yoon. “However, remember that there can be strong imitative (模仿的) effects when we put on virtual masks. ”

Karambelas, a junior at Mira Costa High School in Manhattan Beach，started a Permaculture(永续栽培) Club at school this year to make her fellow students more aware of ways to grow food “in harmony with nature”, and chose the aquaponics(鱼菜共生)project as a way to promote the message.

With Garcia’s help, they completed the project in a weekend, building a handsome two-tiered, 4-by-8-foot redwood structure in one of the school’s courtyards that would easily fit in a front yard, a patio (露台)or even a balcony.

Many of the materials were donated, Karambelas said, but it would have cost her about $1,500 to build the structure at full price. The materials included 26 redwood boards, pond liners, Arqlite Smart Gravel—lightweight nuggets made from recycled food-safe plastics—PVC pipes,40 small goldfish and an Oase AquaMax Eco Classic 3600 pump, which Garcia recommended because of its low energy use.

The lower box is covered with a pond liner, filled with water and the little fish. Garcia helped install the pump, which pushes the water from the fish tier to the vegetables planted in Smart Gravel above. The constantly recycling water drenches(使湿透)the planting boxes, and the run-off drips back into the fish tank, keeping the water aerated(使透气).

Students’ response has been positive, Karambelas said, and she’s hoping the project can create enough interest to attract more members to her new club next year.