It was a hot, humid day, and my brother Walt and I had decided that the only way to survive it would be to go swimming in a deep swimming hole across Mr. Blickez's pasture(牧场) and through some woods.

    The only problem with our plan was that this pasture was guarded by a huge, mean Hereford bull. Mr. Blickez had told us that Elsie was them eanest bull in the township, maybe even the county, and we believed him. But the hotter it got, the more we thought there was something doubtful about his claim. For one thing, we remembered Mr. Blickez liked telling tall tales; for another, Elsie seemed like an odd name for a bull.

    Finally, I talked Mom into asking permission for us to walk through the pasture, but then another problem surfaced. Mom said she would talk to Mr. Blickez if we would take our cousin Joanie along with us. Joanie was almost two years older than me and a head taller. If her teasing ever got around my grade school, it would be all over for me. In fact, I still had a headache from a quarrel with her that morning. “I'm not going swimming with that dumb girl cousin.” I told my mom.

  “Either Joanie goes with, or you stay home alone,” Mom said inher serious tone. I gave in and we set out. On our way across the pasture, Walt yelled suddenly. Elsie had approached him quietly and was licking(舔) his back. Joanie and I dove under the wire fence, but while I was on the ground I looked up and saw that Elsie wasn't a big mean bull after all. She was going to keep licking my brother's back as long as he stood still.

    We had many good days growing up and visiting our secret swimming hole guarded by the so-called “big mean bull”. And as it turned out, fora girl cousin, Joanie hasn't been too bad. She's been one of my best friendsover the years.

    TransNatura International Nature Photo Competition

    The application is open, and all photographers are invited from all over the world, except the jury (评委会) and the organizers. The basic requirement is that the recordings have to be made of natural habitats without disturbing the wildlife. On the photos only wild animals can be included.

    Two categories:

    A Category: Open—any type of nature photography, representing animals, plants, landscape, and so on

    B Category: The art of flying—nature pictures that represent the movement of flying animals and the beauty of flying

    The assessment by the jury: 16th September〜10th October

    Announcement of results: 30th of October

    Exhibition Opening: 23th of November

    The works received will be evaluated and decided upon by an international jury made up of the five persons from Hungary and Romania.

    A total number of competition prizes will be awarded:

    Grand Prize—1,000 Euro;

    1st Prize—600 Euro;

    2nd Prize—400 Euro;

    3rd Prize—200 Euro.

    Entry requirements:

    A participant may enter the competition with at most four pictures per category.

    The pictures for the competition have to be submitted before 15th of September in the form of digital images, in jpg format.

    The participant must have full copyright over the submitted photos.

    The entry fee is 10 Euro for a category, 15 Euro for two categories.

    Additional information can be obtained by e-mail at: transnatura@vadon.ro.

    Do you often feel tired? Is it really because of the large amount of mental work you do? Here is an astonishing and significant fact: Mental work alone can't make us tired. It sounds absurd. But a few years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue (疲劳). To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we would find it full of fatigue toxins(毒素) and fatigue products. But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

    So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of effort as at the beginning. The brain is totally tireless. So what makes us tired?

    Some scientists declare that most of our fatigue comes from our mental and emotional attitudes. One of England's most outstanding scientists, J.A. Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin. In fact, fatigue of purely physical origin is rare.” Dr. Brill, a famous American scientist, goes even further. He declares, “One hundred percent of the fatigue of a sitting worker in good health is due to emotional problems.”

    What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated —— those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

    Measles (麻疹), which once killed 450 children each year and disabled even more, was nearly wiped out in the United States 14 years ago by the universal use of the MMR vaccine (疫苗). But the disease is making a comeback, caused by a growing anti-vaccine movement and misinformation that is spreading quickly. Already this year, 115 measles cases have been reported in the USA, compared with 189 for all of last year.

    The numbers might sound small, but they are the leading edge of a dangerous trend. When vaccination rates are very high, as they still are in the nation as a whole, everyone is protected. This is called "herd immunity", which protects the people who get hurt easily, including those who can't be vaccinated for medical reasons, babies too young to get vaccinated and people on whom the vaccine doesn't work.

    But herd immunity works only when nearly the whole herd joins in. When some refuse vaccination and seek a free ride, immunity breaks down and everyone is in even bigger danger. That's exactly what is happening in small neighborhoods around the country from Orange County, California, where 22 measles cases were reported this month, to Brooklyn, N.Y., where a 17-year-old caused an outbreak last year.

    The resistance to vaccine has continued for decades, and it is driven by a real but very small risk. Those who refuse to take that risk selfishly make others suffer.

    Making things worse are state laws that make it too easy to opt out (决定不参加) of what are supposed to be required vaccines for all children entering kindergarten. Seventeen states allow parents to get an exemption (豁免), sometimes just by signing a paper saying they personally object to a vaccine.

    Now, several states are moving to tighten laws by adding new regulations for opting out. But no one does enough to limit exemptions. Parents ought to be able to opt out only for limited medical or religious reasons. But personal opinions? Not good enough. Everyone enjoys the life-saving benefits vaccines provide, but they'll exist only as long as everyone shares in the risks.

    Parents often believe that they have a good relationship with their teenagers. But last summer, Joanna and Henry noticed a change in their older son. Suddenly he seemed to be talking far more to his friends than to his parents. "The door to his room is always shut." Joanna noted.

    Tina and Mark noticed similar changes in their 14-year-old daughter. "She used to sit in my arms on the sofa and talk with me," said Mark. "Now we joke that she does this only when she wants something. Sometimes she wants to be treated like a little girl and sometimes like a young lady. The problem is figuring out which time is which."

    Before age 11, children like to tell their parents what's on their minds. "In fact, parents are first on the list." said Michael Riera, author of Uncommon Sense for Parents with Teenagers. "This completely changes during the teen years." Riera explained. "They talk to their friends first, then maybe their teachers, and their parents last."

    Parents who know what's going on in their teenagers' lives are in the best position to help them. To break down the wall of silence, parents should create chances to understand what their children want to say, and try to find ways to talk and write to them. And they must give their children a mental (思想的) break, for children also need freedom, though young. Another thing parents should remember is that to be a friend, not a manager, with their children is a better way to know them.

If you've ever seen a sparrow steal your dog food or a crow open a garbage bag, you get a sense of that some birds have learned to take advantage of new feeding opportunities—a clear sign of their intelligence. Scientists have long wondered why certain species of birds are more innovative than others, and whether these capacities stem from larger brains or from a greater number of neurons（神经元）in specific areas of the brain.

It turns out that it's a bit of both, according to a recent study by an international team that included members from McGill University published in Nature Ecology and Evolution.

The researchers used a new technique to estimate the number of neurons in a specific part of the brain called the pallium in 111 bird species. The pallium in birds is equal to the human cerebral cortex（大脑皮层）, which is involved in memory, learning, reasoning, and problem-solving, among other things. When these estimates about neuron numbers in the pallium were combined with information about over 4,000 feeding innovations, the team found that the species with the higher numbers of neurons in the pallium were also likely to be the most innovative.

"The amount of time chicks spend in the nest as their brains develop might also play a crucial role in the evolution of intelligence," says McGill University Emeritus Professor Louis Lefebvre who spent more than 20 years gathering examples of feeding innovations. "Larger species of crows and parrots, which are known for their intelligence, spend longer in the nest, which allows more time for the brain to grow and accumulate pallial neurons."

The results of the study help to deal with previously opposed views of the evolution and significance of brain size and show how a life-history perspective helps to understand the evolution of cognition.