【推荐1】Birds have nostrils on their beaks (喙) that can help them smell all kinds of things. When animals breathe air, they can also breathe in different smells.

The nose can pick up on smells and send information to the brain by the olfactory system. We have an olfactory system, too. This system can help animals understand the world through a sense of smell.

Maybe you’ve used your olfactory system to smell your breakfast, lunch, and dinner or you’re your new school books.

Birds can also use their olfactory systems to sniff out food. The kiwi bird uses its long beak to dig into the dirt. Its nostrils are on the outside and very tip of its beak. It’s thought that they use that sense of smell to pick up chemicals (化学物质) emitted by their food — grubs, worms, and other things that are in the ground.

One bird of prey that has a really great sense of smell are turkey vultures. Vultures are scavengers, meaning they eat dead animals. They have a fantastic sense of smell. They use their nose to pick up chemicals from things that are decaying (腐烂). Turkey vultures have one of the strongest senses of smells among birds. They have been known to smell food that was over a mile away.

But albatrosses, which can have wingspans around ten feet, have been known to sniff out food from even greater distances — about 12 miles away. These seabirds can pick up chemicals from dead fish or groups of fish. They can even sense the smell that krill give off when they are eaten by fish. That helps them find the fish via the krill.

While a sense of smell is helpful for birds, it isn’t the only useful or even sometimes the strongest sense — they also use their senses of hearing, sight, and taste. The next time you watch your chickens, or other birds in the neighborhood, maybe you can observe how they use all these senses.

【推荐2】Caffeine myth or caffeine fact? It’s not always easy to know. Chances are you have some misunderstanding about caffeine. Read on. Here are some of the most common myths about caffeine and some facts have been gathered to shed light on them.

Myth one: Caffeine is addictive

Caffeine is a stimulant(起刺激作用的食物) to the central nervous system, and regular use of caffeine does cause mild physical dependence. But caffeine doesn’t threaten your physical, social, or economic health the way addictive drugs do. If you stop taking caffeine abruptly, you may have symptoms for a day or more, especially when you have been used to consuming two or more cups of coffee a day. However, caffeine does no cause the severity of withdrawal or harmful drug-seeking behaviors as drugs or alcohol. For this reason, most experts don’t consider caffeine dependence a serious addiction.

Myth two: Caffeine probably causes insomnia(失眠症)

Processed mainly through the liver, caffeine has a relatively short half-life. This means you can get rid of half of it within about five to seven hours on average. After eight to ten hours, 75% of the caffeine is gone. For most people, a cup of coffee or two in the morning won’t prevent them from sleeping at night. Consuming caffeine later in the day, however, can interfere with sleep. Your sleep won’t be affected if you don’t consume caffeine at least six hours before going to bed.

Myth three: Caffeine harms children

As of 2004, children aged 6 to 9 consumed about milligrams of caffeine per day. This is well within the recommended limit. However, energy drinks that contain a lot of caffeine are becoming increasingly popular, so this number may go up. Some kids are sensitive to caffeine, developing temporary anxiety or irritability, with a “crash” afterwards. Also, most caffeine that kids drink is in sodas, energy drinks, or sweetened teas, all of which have high sugar content. These empty calories put kids at higher risk for obesity. Even if the caffeine itself isn’t harmful, caffeinated drinks are generally not good for kids.

Myth four: Caffeine has no health benefits

Caffeine has few proven health benefits. But the list of caffeine’s potential benefits is interesting. Any regular coffee drinkers may tell you that caffeine improves alertness, concentration, energy and clear-headedness. Scientific studies support these subjective finding. One French study even showed a slower decline in cognitive ability among women who consumed caffeine. Other possible benefits include helping certain types of headaches. These research findings are interesting, but still need to be proven.

【推荐3】"Oh, my God! Did I really just send that text?" Most people have said something that they wish they could take back. And if they had paused to think about it first, they probably would have acted differently. Pausing doesn't pay off just when you speak. Scientific studies have shown that making a habit of pausing before you do something can actually have a big impact on how your life turns out.

In making decisions we rely on two areas of the brain. One area creates and processes emotions; the other governs logical thought. The type of decision, how we feel about it, and how prepared we are to handle it help determine which brain area has the most influence.

But our age also plays an important role. Thinking through the consequences of one's actions is actually harder for teens because the area controlling logical (逻辑的)thought is not fully developed until around age 25. This is why teens often feel an intense emotional drive to act impulsively(冲动地)---it's how their brains are structured! Though this tendency to act without considering the outcomes can lead to problematic situations, impulsivity during the developmental years evolves because it makes teens more open to new experiences and ideas. This openness helps teens to become independent adults.

The key to making impulsivity work for you instead of against you is to train your brain by practicing pausing. This doesn't mean you stop taking risks or being open to new experiences. But you won't know if the risk is worth it until you think it through. Deciding to take a risk based on logic shows self-control, not impulsivity.

What are different ways to pause? You might take a deep breath, count to 10, or ask "Is this worth it?" different strategies work for different people. Whatever works for you, keep doing it! By practicing pausing, you can actually change your brain. This means that over time, pausing, instead of immediately reacting, becomes your "natural" response.

And with this change, people are on their way to enjoying the life rewards that come with high levels of self-control---even if they weren't natural-born pausers!

【推荐2】October 15th is Global Handwashing Day. Activities are planned in more than twenty countries to get millions of people in the developing world to wash their hands with soap.

Experts say people around the world wash their hands but very few use soap at so-called critical moments. These include after using the toilet, after cleaning a baby and before touching food.

Global Handwashing Day is the idea of the Public-Private Partnership for hand washing with soap. The goal, they say, is to create a culture of hand washing with soap. The organizers say all soap is equally effective at removing disease-causing germs (细菌). They say the correct way to wash is to wet your hands with a small amount of water and cover them with soap. Rub it into all areas, including under the fingernails. Then, wash well under running water. Finally, dry your hands with a clean cloth.

The Partnership says soap is important because it increases the time that people spend washing. Soap also helps to break up the dirt that holds most of the germs. And it usually leaves a pleasant smell, which increases the chances that people will wash again.

It also says that washing hands with soap before eating and after using the toilet could save more lives than any medicine. It could help reduce cases of diarrhea (痢疾), which is the second leading cause of child deaths, killing more than one and a half million children a year, by almost half.

【推荐3】When our Scottish puppy reached doggie adolescence, she suddenly stopped obeying my commands. Previously, if I called “come,” Annie would fly across our yard to my arms. Now, the 8-month-old gave me an aggressive “make me” look and ran the other way.

Our dog trainer advised us to stop complaining. “She's a teenager,” she said. Now, a new study is backing that up: Dogs, it says, experience an oversensitive period just like human teenagers. “There is abundant folk knowledge that the behavior of adolescents differs from younger or older dogs,” says Barbara Smuts.

Puppies bond with humans much as children do. “But owners often feel like they're failing when their puppies reach adolescence,” about 8 months for most dogs, says Lucy Asher. Like teenagers, adolescent dogs can disregard and disobey their owners. Indeed, teenage dogs are the most likely age group to land in U.S. shelters.

To see exactly how adolescence changes dog behavior, Asher and her team monitored 70 female dogs being raised as potential guide dogs. They asked caregivers to score the puppies on separation-related behaviors, like trembling when left behind. Dogs with high scores on this behavior entered adolescence earlier-at about 5 months, compared with 8 months for those with lower scores. Various factors cause human teenage girls with poor parental relationships to also enter adolescence at a younger age. Thus, similar to humans, dogs that have bad relationships with their caregivers see changes in their development.

According to Smuts, adolescent dogs that were stressed by separation from their caregiver also increasingly disobeyed that person, showing the insecurity of human teenagers.

Because of the similarity between adolescent pups and humans, dogs can serve as a model species for studying adolescence in humans, the scientists say. The temporary nature of dogs which disobey the owners may make us worry less when our pups suddenly get minds of their own.