Every year millions of breeding monarch butterflies in the U. S. and southern Canada search for milkweed plants on which to lay their eggs. Concern over shrinking habitat （居住地）has urged conservationists to create monarch-friendly spaces along roadsides, which are more than enough within the butterflies range and usually publicly owned. But traffic noise stresses monarch caterpillars out, a new study finds. They eventually do become desensitized to it—but that might cause trouble to them later on, too. 

Noise pollution is known to affect the lives of birds, whales and other creatures. But until recently, scientists had never tested whether it leads to a stress response in insects. When Andy Davis, a conservation physiologist at the University of Georgia, noticed online videos of roadside monarch caterpillars apparently trembling as cars came by, he wondered how the constant noise might affect them. Davis built a custom caterpillar heart monitor, fitting a small sensor into a microscope to precisely measure monarch caterpillars' heart rates as they listened to recordings of traffic sounds in the laboratory.

The hearts of caterpillars exposed to highway noise for two hours beat 17 percent faster than those of caterpillars in a silent room. But the heart rates of the noise-exposed group returned to baseline levels after hearing the traffic sounds nonstop for their entire 12-day development period, Davis and his colleagues reported in May in Biology Letters. 

This desensitization could be problematic when the caterpillars become adults, Davis says. A rapid stress response is vital for monarch butterflies on their two-month journey to spend winters in Mexico, as they narrowly escape predators（捕食者）and fight wind currents. 

Whether a noisy developmental period reduces monarchs' survival rates remains unknown, notes Ryan Norris, an ecologist at the University of Guelph in Ontario, who was not involved in the study. But in any case, he believes roadside habitat almost certainly drive up the butterflies' death rates as a result of crashes with cars. " There is so much potential road habitat for monarchs and other insects一it would be such a nice thing to capitalize on, " Norris says. ‌" But you just can't get around the traffic. " Davis adds: " I think roads and monarchs just don't mix. "

I had a great time producing a short film with my other crew members, myself in the scene, the light and shadow seen through the camera lens, and the warmth of intimate friendship.

It was through a short film festival at our school that I had the chance to make a short film. Our film crew decided to develop a simple story focusing on friendship, growth and hospice care(临终关怀). The story was set around Christmas Eve where two kids are assigned to accompany a terminally(晚期地)ill kid during her last few days. There were conflicts and tears, but finally, the kids became close friends on Christmas Day, which was just before the ill kid passed away. We expected it to be a warm story mingled with a little sorrow and planned to name it Merry Christmas.

In producing our short film, things weren't so easy at first. We were able to use a crew member's house for shooting but it was far from the city. We experienced technical problems, among others.

It was the middle of winter, and emotional collapses of our actors were wearing our patience thin. Pale light the snow and the nervous excitement of telling ghost stories accompanied our night scene shooting.

As the cameraman, I adjusted the camera to produce the best composition of the image, specially designed with the director to achieve the desired effect. I held the camera in one hand and the spotlight in the other till midnight to finish our night scene.

As we decorated the tiny Christmas tree and looked at each other's drowsy faces in the warm light, we couldn't help wolfing down the dessert the host family offered before making the other cakes and fruits for our props(道具). We made jokes about the look of the giant spotlight which was like a huge shiny umbrella. We somehow felt closer to the characters in the film, experiencing what they experience leisurely chatting about films and songs in the serenity of night and forming a special connection with each other.

Through this experience, I realized that making short films is not only about creating art, but also about creating shared stories and bonds that last a lifetime.

C

Almost all new parents struggle to get enough sleep while caring for their newborns. For some penguin （企鹅） parents, though, periods of sleep are especially short.

Researchers recently found that Chinstrap penguins only sleep for about four seconds at a time in order to protect their eggs and newborn chicks. They do this thousands of times throughout the day. The short "microsleeps" total around 11 hours each day. The microsleeps appear to be enough to keep the parents going for many weeks.

Niels Rattenborg, a sleep researcher at the Max Planck Institute for Biological Intelligence in Germany, said, "What's surprising is that the penguins are able to function okay and successfully raise their young."

Chinstrap penguins usually lay their eggs in November in nests made up of small rocks. Mated （交配的） pairs share parenting responsibilities. One parent usually watches the eggs and chicks alone while the other goes off fishing for family meals. Adult penguins don't face many natural enemies in the mating season. But large birds called brown skuas eat the penguin eggs and small chicks. Other adult penguins may also try to steal the small rocks from the nests, so penguin parents must always be on guard.

For the first time, scientists followed the sleeping behavior of Chinstrap penguins. They did this by attaching devices that measure brain waves. They collected data on 14 adults over 11 days on King George Island off the coast of Antarctica.

Won Young Lee, a biologist at the Korean Polar Research Institute, thought of the idea for the study when he saw mating penguins often blinking （眨） their eyes and possibly sleeping. But the team needed to record brain waves to confirm the animals were sleeping. "For these penguins, microsleeps have some restorative functions," he said. He added that they would not survive without it.

The researchers didn't collect sleep data outside the mating season. But they suspect that the penguins may sleep for longer periods at other times of the year.