Seal(海豹) seizes raft

    This seal really rocked the boat when he found himself an unusual place to hang out. After the seal came across a boat in the harbor where he lives, he fell inside and wouldn't budge for four days.

“One morning the seal just pulled himself aboard,” says Ed Stubbings, who owns the boat-turned-bed. Probably thinking the boat was a rock, the seal made himself at home. The seal didn't move an inch—--not even to eat or drink.

    Stubbings was a little worried that the 500-pound animal might sink it. Luckily on the fifth day, the seal fell back into the water and swam off.

Alligator(短吻鳄)gets new tail

When Mr. Stubbs the alligator swims through his pool at the Phoenix Herpetological Society, he looks like any other gator—--except that his tail is made of rubber. Mr. Stubbs is the first alligator known to wear an artificial tail.

    Mr. Stubbs was brought to the society nine years ago. “His tail was missing when he arrived,” says President Russ Johnson. Mr. Stubbs couldn't walk or swim properly. “We showed him how to swim in the water,” Johnson says. “But that hurt his back.” Later, the scientists used rubber to build an artificial tail attached to Mr. Stubbs's back legs. “Once we put the tail on him, he walked with ease,” Johnson says.

Dog delivers papers

    Morgan started her “paper route” when she was young. One day as Morgan and her owner Bill set out on a walk, she spotted a rolled-up paper. To Bill's surprise, Morgan grabbed the object in her mouth, walked back to the house, and dropped it on the doorstep. Morgan enjoyed the activity so much that she wanted to deliver every paper she saw on her walks.

Now three-year-old Morgan brings the paper to her owner and neighbors, even in bad weather. “Morgan has a natural instinct(本能) to carry things with her mouth,” dog behaviorist Pat Miller says. “And she feels rewarded by the activity, so she keeps it up.”

    At least 35 percent of Beijing households will be covered by family doctor service at the end of this year. All local households will enjoy the service as of 2020, according to the Municipal Health and Family Planning Commission.

    It is good that Chinese communities can expect more general practitioners(从业者)，who do not specialize in any particular area of medicine but who are able to treat the general health problems for people of all ages. By the end of last year over 8 million residents in Beijing had reportedly signed up for family doctor services, accounting for more than 40 percent of the city's permanent population.

    Since 2009 China has launched scores of programs nationwide to ensure citizens have fairer access to elementary public health services ，among which the introduction of family doctors has been one of the most successful. Some regions have issued guidelines on the promotion of the family doctor service. And four months ago, Premier Li Keqiang said in this year's Government Work Report that the service should cover at least 85 percent of the Chinese cities this year.

    The expanding coverage, however, may not guarantee more residents will be offered quality medical services.

    Family doctors in some places rarely visit the families they are assigned to, and some of them have been struggling to solve patients problems either because of their unfitness or because they have too many households to attend to. In some cases, a family doctor might be assigned to see hundreds of residents a day.

    That highlights the need to better the arrangement of medical resources and to offer proper encouragement to family doctors, who should get patients to make appointments rather than employ temporary arrangements.

    Fashions have a lot of rules. Most of them, however, are just wrong. But there's one rule that goes beyond tradition and into the field of scientific study of the brain: Black clothes are slimming. It all comes down to how your visual system processes the light. The below holes in each square are the same in size, yet the white hole looks bigger than the black hole.

    In the 1500s, Galileo Galilei noticed that some of the planets looked larger when viewed with the naked eye than they did when viewed through a telescope, making the white light of Venus appear eight to ten times larger than Jupiter in the night sky. He knew something strange must be going on with his vision to cause this illusion, but he wasn't sure what it was. Luckily, scientists never stopped wondering, and in 2014, they figured it out.

    Our visual system operates via two main channels: "on" neurons (神经元) that are sensitive to light things and "off" neurons that are sensitive to dark things. When it came to the dark "off" neurons, the researchers found that they responded predictably to dark shapes on a light background the greater the contrast between the two, the more active these neurons were. But the light on" neurons behaved unpredictably. Even with the same amount of contrast, light objects on a dark background caused a greater response in these neurons.

    This phenomenon makes some sense, evolutionarily speaking. In the dark of night, you'd want to be able to take in every bit of light you can get, so a visual system that enlarges light objects on a dark background could be very useful. However, it's not that hard to see dark objects in the light of day. It has some effects in the colors of your clothes and in the appearance of the planets—the brighter appearance of Venus in the night sky makes it look bigger than the darker Jupiter.

Robots have long been drawing inspiration from animals, with the creation of robot dogs or snake-shaped robots. And yet, the field of robotics is far less enthusiastic about the other kind of living things—plants. Barbara Mazzolai, an Italian roboticist owes this to a misconception about plant behavior: that they cannot move or think. "It's not true at all," she says. To challenge this view, Dr Mazzolai and her team recently launched a machine called "FiloBot", a robot based on a climbing species.

To survive, a climbing plant must switch between several different behaviors. In forest environments, it must first grow out of the soil and travel along the ground in search of a support to hold onto, such as a nearby tree. Once a support is located, though, the plant fixes itself around the object and then growing towards the light. To choose the best angle to grow upwards, a climbing plant uses its shoots(芽) to receive information about light and gravity.

FiloBot has sensors on its main shoot. It can 3D-print its body with plastic and grow at a controllable rate. These functions researchers found, enabled FiloBot to cross gaps, and find things to attach to. The lack of heavy on-board computing device means that it is light and requires minimal care, while its slow pace means that it doesn't disturb things around it, making it possible to move through a complex, unseen environment, or monitoring disaster sites.

For now, FiloBot is still being tested. Its tendrils(卷须) have not left the laboratory. Still, it has already been employed in deconstructing plant behaviour. For example, it was long assumed that climbing plants find their supports by growing towards shade, though the exact mechanism was unclear. FiloBot could imitate this behaviour by detecting far-red light, which is typical of shaded areas, providing clues to how plants do it.

Dr Mazzolai hopes that such projects will inspire other roboticists to take their cues from plants and develop completely new technologies.