1 . What Does Humanely Raised Mean?

Chicken labels often bear claims related to how the birds were raised. But “humane (人道的) treatment” means different things to different groups-and may not match what you'd expect. Below, several labels are rated on how well they meet those expectations. (Note that the score for animal welfare shown below relates to chicken raised for meat.)

USDA Organic		Animal Welfare Approved
Overall Score	5	Overall Score	5
Animal Welfare	1	Animal Welfare	5
Overall, this is one of the most meaningful labels a food can carry, indicating that producers stick to national standards requiring that animals be raised without added antibiotics (抗生素). But it falls short as far as animal welfare is concerned mainly because the Department of Agriculture hasn't introduced relevant rules on outdoor access.		Standards for this label are set by a nonprofit group, A Greener World. Chickens must have access to the outdoors and be freely raised on family farms, meaning the farmer owns the animals. Painful procedures are forbidden, and birds must be stunned (打昏)before slaughter (屠宰).
Certified Humane Raised & Handled		American Humane Certified
Overall Score	4	Overall Score	3
Animal Welfare	4	Animal Welfare	3
Humane Farm Animal Care, a nonprofit, monitors this label. Outdoor access isn't required, but birds are given slightly more room than the industry norm and living conditions are carefully controlled. An “animal welfare officer” must monitor slaughter to ensure that proper procedures are followed.		Under this label from the nonprofit American Humane Association, outdoor access isn't required and indoor space can be minimal. Birds must be given at least 4 hours of continual darkness, which is more than required but less than what some other animal welfare programs ask for.
1          2          3          4          5 Worse- - - - - Better

2 . Vampire bats live in the warmer areas of Central and South America. They are the only warm-blooded animals with a blood-only diet. They live in groups that can number from the tens to thousands of individuals.

Most people would not think of friendship and cooperation(合作)when considering vampire bats. But experts say maybe we should. New research shows that vampire bats have deeper social relationship with one another than scientists had thought. The study shows that vampire bats form friendships and meet at feeding time to hunt together.

Researchers attached small devices to 50 vampire bats in Panama to follow their path as they feed at night. The bats drink blood from wounds they cause on cows in open fields. Female bats were chosen in the study, as researchers believe they have stronger social relationships than males.

Twenty-three bats born in the wild had been caught and studied for about two years for related research into bat social behavior. Social connections had already been observed among some of them. They live together in trees, clean each other and share meals. The scientists used tiny sensor devices on the flying bats to learn whether their hunting behavior was also social. The sensor data showed that the bats would often join a “friend” while searching for food.

Gerald Carter is a scientist with the Ohio State University and the Smithsonian Tropical Research Institute. He led the research published in the journal PLOS Biology. “This study opens up an exciting new window into the social lives of these animals.” he said, “Each bat maintains its own network of close cooperative social connections.”

The researchers guess that the bats join their friends during the hunt to help each other. They think the bats might exchange information about prey(猎物)position or access to an open wound for feeding.

Simon Ripperger, a researcher at the Smithsonia Tropical Research Institute and a writer of the study said people’s first response to vampire bats is usually fear. He added, “but once you tell them about their complex social lives, they are quite surprised that we can find such behavior that is somewhat similar to what humans do-and which one would maybe expect in primates(灵长类)—in bats.”

3 . Here's why Disney World doesn't have mosquitoes(蚊子)

There is a lot that goes into making Disney World the "Most Magical Place on Earth”. Considering Walt Disney World is in Central Florida, and has various amusement parks at Walt Disney World, there is one thing missing from the huge property that you may not have even noticed: mosquitoes.     1    .

Naturally, this is due to efforts from Walt Disney World staff to ensure health among guests and a uniform consumer experiences.    2    Disney employs a project called the “Mosquito Surveillance Program“ which can avoid the noisy pests and keep visitors safe from the threat of disease.

    3    Mosquitoes are attracted to the gas, which is one reason why they are so good at finding humans, as we breathe it out constantly. Once caught, the mosquitoes are then frozen and studied in labs where experts discover the best ways to keep mosquitoes off of our skin when we arrive on-site.

    4    Due to the birds' immunity to mosquito-borne viruses such as West Nile they can be used to observe the presence of the virus without experiencing any harmful symptoms(症状)after that. The chickens are kept in cages, unlike flying birds that would travel long distances. So, if a virus is detected, it is easy for Disney to find out exactly which part of their parks has been affected by viral mosquitoes.

Occasionally, Disney has had to close certain sections of their park during the busiest times.     5     It's time of year when we can finally get back outdoors in Disney with family and friends without worry.

4 . As our boat moves quickly up and down in a windy ice-filled small bay, I try to judge the health condition of the polar bear (北极熊)in front of me. We are in Franz Josef Land, a remote part of Russia between the Barents Sea and the Arctic Ocean.

While offshore bears follow the sea ice, hunting seals (海豹)on ice all year round, bears that live by the sea spend their summers on land and are forced to search for whatever they can find. Relying on low-calorie meals such as the eggs of nesting seabirds, it is harder for these bears to pack on the pounds. Researchers recently found that offshore bears around the Barents Sea are some of the most polluted animals on Earth. This is a direct consequence of the seals they feed on.

Over a period of 14 years' study, Heli Routti from the Norwegian Polar Institute found that offshore female bears were in a better health, having greater body weight, than female bears by the sea, but on average their levels of pollutants called PFASs are 33 percent higher.

PFASs are used to make industrial products which are poisonous and degrade (降解)very slowly. These pollutants find their way to the Arctic through air, where they fall in snow and gradually add up in the ice. As the ice melts every summer, the PFASs go into the water, where they enter the food chain. They eventually make their way into the fat that keeps seals warm and from there into the bears that eat them.

During my 15 days in Franz Josef Land, I saw five bears, all living by the sea. Each looked relatively healthy. There are signs that these bears are dealing with the global-warming-caused ice loss relatively well. “The bears, so far, seem to be handling the sea ice loss,” says Andrew Derocher at the University of Alberta, who worked with Routti on the study, “But I'm sure that's going to change if the speed of ice loss increases sharply in the area.”