Baby girls make their way to dolls as soon as they can crawl, while boys will head for the toy cars,  a study has shown. The findings, the first to show consistent differences in very young babies, suggest there is a biological basis to their preferences.

    Psychologists Dr Brenda Todd from City University London carried out an experiment involving 90 babies aged nine months to 36 months. They were allowed to choose from seven toys. Some were boys' toys - a car, a digger, a ball and a blue teddy.  The rest were girls' toys: a pink teddy, a doll and a cooking set. They were placed a meter away from the toys, and could pick whichever toy they liked. Their choice and the amount of time they spent playing with each toy were recorded.

    Of the youngest children (nine to 14 months), girls spent much longer playing with the doll than boys, and boys spent much more time with the car and ball than the girls did. Among the two-and three-year-olds, girls spent 50 percent of the time playing with the doll while only two boys briefly touched it. The boys spent almost 90 percent of their time playing with cars, which the girls barely touched. There was no link between the parents' view on which toys were more appropriate for boys or girls, and the children's choice.

    Dr Brenda Todd said: “Children of this age are already exposed to much socialization. Boys may be given ‘toys that go' while girls get toys they can care for, which may help shape their preference. But these findings agree with the former idea that children show natural interests in particular kinds of toys. There could be a biological basis for their choices. Males through evolution have been adapted to prefer moving objects, probably through hunting instincts（本能）, while girls prefer warmer colors such as pink, the color of a newborn baby.”

    Three boys were enjoying themselves in their hometown of Bovina, Mississippi .However, their lives were turned upside down when they discovered the jawbone of a Mastodon (齿乳象).

    Brothers Shawn and Caid Sellers and cousin Michael Mahalitc found the prehistoric bone in a piece of earth that was recently plowed (犁、耕)."I thought it was a log," Caid said. "I tried to pick it up and it was really heavy and I saw teeth on it." The bone weighed about 50 pounds. They eventually got the bone to their home and fitted it in their tub (浴盆), but it took their collective strength, might and a golf cart, to carry the large Mastodon bone.

    "They didn't expect to find that," Michael's mom said. "Now that they have, I believe that they will be more aware of their surroundings and what they're digging up when they are digging and playing."

    "We've gotten a lot of petrified (石化的) wood and Civil War relics from the area and that's what I thought it was," the brothers' mother said. "This is our first set of teeth we've found. So we thought it was their imagination. We were quite surprised to see that it was not their imagination."

    They were exploring near the brothers' home. Lo and behold (真想不到), they saw what they thought resembled a fossil. It was the curator of paleontology (古生物负责人) of the Mississippi Museum of Natural Science, George Phillips, who first identified the bone as a "very mature individual."

    The Mastodon was a mammal who lived during the prehistoric times. They had long tusks and trunks, like elephants. They were clearly different from their modern-day counterparts, as well as woolly mammoths (猛犸).

    Can I talk about salary at work? In a word: yes. As HR company Insperity put it in a recent blog post: Can your employees discuss their salaries or wages with their co-workers? Yes. Even if you have a company policy against it? Yes.

    The freedom to discuss your salary at work is a protected right under federal labor law. The National Labor Relations Act of 1935 protects your right to discuss the conditions of your employment, including issues related to safety and pay, even when you're not protected by a union.

    Talking about salary with colleagues can be uncomfortable, since there's such a taboo about discussing money matters, but it's an important step towards achieving equal pay for equal work. One barrier, however, stems from how we think of our own financial worth. Too many people I talk to wrongly consider their salary a reflection of their worthiness, a statement about their skills, experience, or value. At the end of the day, if we can all separate our self-worth from our salaries a bit more, it'll become easier to talk frankly with our colleagues.

    Asking about money outright can be tough, so one trick I've picked up along the way is to ask for your colleagues to confirm or deny. For instance, you might volunteer your salary first and ask "Does that sound about right to you?" by way of comparison. Or, let's say you're interviewing for a promotion to become a manager. You might ask a fellow manager about the kind of salary you should expect by saying, “I'm seeing salaries for this kind of position ranging from $65, 000 to$70, 000—does that seem accurate to you?" This way, even if your colleague isn't comfortable sharing their salary outright, they can help you identify if your expectations are on point or way off.

    City trees grow faster and die younger than trees in rural forestry, a new study finds. Over their lifetimes, then, urban trees will likely absorb less CO₂ from the air thah forest trees.

    As we all know, the earth would be freezing or burning hot without CO₂. However, CO₂ is a greenhouse gas, meaning it traps energy from the sun as/heat. That makes temperatures near the ground rise. Human activities, especially the widespread burning-of fossil(化石)fuels, have been sending extra greenhouse gases into the air. This has led to a rise in average temperatures across the globe.

    Studies had shown forests readily absorb CO₂, but there hadn't been much data on whether city trees grow, die and absorb CO₂ at the same rate as forest trees do. So some researchers decided to find out.

    To figure out how quickly trees were growing, researchers tracked their diameters (the width of their trunks) between 2005 and 2014. A tree's diameter increases as it grows, just as a person's waist size increases as they gain weight. About half the weight of a tree is carbon, research has shown. Most of the rest is water. Over the nine years' tracking, the researchers found city trees absorbed four times as much carbon from the air as forest trees. However, they were twice as likely to die. So over the lifetime of each type of tree, forest trees actually absorbed more CO₂.

    City trees grew faster because they had less competition for light from their neighbors. In a forest, trees tend to grow close together, shading their neighbors. Street trees also benefit from higher levels of nitrogen (氮)in rainwater. Nitrogen helps plants grow. Waste gases from gas-burning cars also contain nitrogen, thus enriching city air with nitrogen. Later, rainwater may wash much of it to the ground. Some street trees may also have better access to water than trees in the country because the underground water pipes can leak.

Before traveling to Lake Tahoe, make sure your plans are in order. Here are several vacation packages to the area offered online. Easily find the perfect route or simply build your own to experience the wonders of Lake Tahoe.

Get Outdoors in Lake Tahoe Package

Get outdoors and explore! With this fun vacation package, you can stay in the Lake Tahoe area for three nights and have a few adventures along the way. This package also features Lake Tahoe Sport Fishing, allowing guests to get out and fish!

Package includes: 3 nights' lodging（住宿）in your choice of over 33 hotels.

Lake Tahoe Romantic Getaway Package

Lake Tahoe Romantic Getaway Package is perfect for people who want to have a romantic time. It also includes the Lake Tahoe Emerald Bay Sunset Cruise on the Bleu Wave, which allows you the chance to see the beautiful surroundings of Lake Tahoe.

Package includes: 4 nights' lodging in your choice of over 11 hotels.

Lake Tahoe Family Vacation Package

Due to the amazing sights, there are lots of activities in this package to take part in. If your next trip happens to be in the Lake Tahoe area, then consider booking the Lake Tahoe Family Vacation Package. Everyone is suitable to visit.

Package includes: 3 nights' lodging in your choice of over 11 hotels.

Lake Tahoe Weekend Getaway Package

Lake Tahoe Weekend Getaway Package is great for people of all ages, so this is a great choice for families. It also includes a Lake Tahoe Emerald Bay Cruise, which takes place aboard the Bleu Wave.

Package includes: 2 nights' lodging in your choice of over 22 hotels.