A biologist from the National Park Service discovered a rare and unusual mammoth(猛犸) skull(颅骨) buried in a 13,000-year-old rock layer on the Santa Rosa Island, the second largest landmass in the Channel Islands, California. The fossil of the extinct giant animal is leaving many paleontologists(古生物学家) scratching their heads. Despite the fact that it's possibly the best preserved mammoth skull ever found and of high scientific importance, the species of the individual it belonged to can't seem to be identified yet—it's too big to be a pygmy(特别矮小的) mammoth and too small to have come from a Columbian mammoth. Some say it's a new species while others believe the truth lies somewhere in between.

    The first mammoths showed up in North America around two million years ago, but it was only during the last two ice ages that the Columbian species, which could grow to be up to 14 feet tall, made its way to the Channel Islands 100 miles west of Los Angeles. Once the ice melted, many populations became trapped on the island and evolved into pygmy mammoths, an endemic species(地方种) to the Channel Islands which grew only to six feet tall.

    Judging from its size, the newly found mammoth skull doesn't seem to fit any of the two species, Columbian or pygmy. To make things even more confusing, one of its two tusks(象牙) is nearly five feet long and coiled in a manner that resembles those of fully grown mammoths but the left tusk is shorter and sloped, more like a juvenile(青少年).

    This has caused some scientists to say the Santa Rose skull may belong to a transitional species. Whatever's the case, a following examination of the mammoth's teeth should put the matter to rest. The analysis will also tell us how old the mammoth was when it died, so we can tell for sure whether it was an adult or juvenile.

    More interesting than the mammoth's lineage, however, might be its story. The giant mammal lived 13,000 years ago or roughly the same timeline of the “Arlington Man”, a 13,000-year-old human skeleton also found on Santa Rosa. Some 3,000 years later humans were already spread throughout the continent and the Channel Islands' mammoth went extinct. The present finding might help reveal a link between the two.

    The remains also seem to confirm a long-held assumption that there were two mammoth migrations to the Channel Islands. “The discovery of this mammoth skull increases the probability that there were at least two migrations of Columbian mammoths to the island: during the most recent ice age 10,000 to 30,000 years ago, as well as the previous ice age that occurred about 150,000 years ago,” said USGS geologist Dan Muhs.

    Why is pink or purple a color for girls and blue or brown for boys?

    The answer depends largely on cultural values as well as personal experiences. To the Egyptians, green was a color that represented the hope and joy of spring, while for Muslims, it means heaven. Red is a symbol of good luck in many cultures. In China, children are given money in a red envelope to bring good fortune in the New Year. For many nations, blue is a symbol of protection and religious beliefs. Greek people often wear a blue necklace hoping to protect themselves against evils（灾祸）.

    People's choice of colors is also influenced by their bodies' reactions （反应）toward them. Green is said to be the most restful color. It has the ability to reduce pain and relax people both mentally and physically. People who work in green environment have been found to have fewer stomach aches.

    Red can cause a person's blood pressure to rise and increase people's appetites（食欲）. Many decorators will include different shades of red in the restaurant. Similarly, many commercial websites will have a red “Buy Now” button because red is a color that easily catches a person's eye.

    Blue is another calming color. Unlike red, blue can cause people to lose appetite. So if you want to eat less, some suggest that eating from blue plates can help.

    The next time you are deciding on what to wear or what color to decorate your room, think about the color carefully.

    If you want to travel from Xi'an to Chengdu by train, it will take about 16 hours. But starting this month, the new Xi'an-Chengdu high-speed railway will shorten this travel time to three hours.

    The 643-kilometer line is China's first high-speed railway to run through the Qinling Mountains, which form a natural boundary (分界线) between China's north and south. With a speed of 250 km per hour, it's also the first mountain-heavy train line to provide a 4G network. Along the way, the train passes through two areas for rare (稀有) wild animals — one for pandas and the other for crested ibises (朱鹮).

    To reduce the railway's influence on the animals, workers and experts have designed and built the railway to be environmentally friendly. There were 345 wild pandas living in the Qinling Mountains. China currently has 1,864 wild pandas in total, according to the Xinhua News Agency.

    To avoid disturbing the pandas, the railway was designed to run through tunnels (隧道) within the area. Protective shields (防护屏) are placed near the entrance of each tunnel to stop animals from going in.

    To protect the thousands of crested ibises that fly near one part of the railway, protective nets have been set up to make sure the birds will not fly into a train.

    The nets are about 32 km long and 4 meters high. Experts tested different shapes and materials for building the nets before making their final choice.

    Here are our suggestions for keeping busy this week. Dive in!

    Take to the waves in Southampton

    Always fancied trying your hand at sailing? Now's your chance. The Southampton Boat Show has plenty of opportunities for visitors to get out on the water to experience boat sailing, power boating or taking a ride on a RIB ― all for free.

    Discover an island on the Thames

    To celebrate Totally Thames, a month-long festival is held at various locations across London. We've discovered 21 of the river's most fascinating islands ― all of them with interesting stories to tell. Make the most of it with our map here.

    Catch great films in Bristol

    Over six days, Encounters Film Festival screens up to 400 films from over 60 different countries. The Bristol festival provides a platform for international filmmakers, and offers a gateway to the likes of the BAFTAs, Oscars and European Film Awards. See here for full details.

Get scientific in London

    Experience the latest, best and most challenging science covering all areas of our lives and universe at New Scientist Live at ExCel London. New Scientist Live is a four-day festival full of ideas and discoveries from the team behind the world's most popular science weekly magazine, featuring four zones Brain & Body, Technology, Earth and Universe as well as talks from experts and over 200 exhibitors.

    Winning literary competitions doesn't always lead to fame. But having a few such wins to boast about does you no harm when approaching editors or agents, so if you have dreams of a writing career, these could be the place to begin. Below is a list of the most interesting competitions. Bear in mind that contests with smaller prizes attract fewer entries and are therefore easier to win.

    Wundor Editions Poetry Competition

    Wundor Editions are looking for creative writers to enter their latest poetry contest. If you happen to be 16 or over, send in a poem on any subject running to as many words as you think you can get away with before the judge's eyes glaze over (兴趣丧失).

    Closing: Nov.30. Prize: £ 500. Entry Fee: £ 10.

    Manning's Pit Poetry Competition

    It doesn't sound very attractive but it seems Manning's Pit is something of a beauty spot with more than its share of wildlife. But it's now under threat. This contest aims of raise funds to help save it. Your task is to write a poem of up to 40 lines about Manning's Pit or a similar treasured and threatened piece of countryside near a town or village.

    Closing: Nov.30. Prizes: £ 100, £ 30, £ 20. Entry Fe: £ 3.

    Commonwealth (英联邦) Short Story Competition

    This contest from Commonwealth Writers is for unpublished short fiction of between 2,000 and 5,000 words aimed at adults. But you have to be a citizen of a Commonwealth country. You can write your story in English, Bengali, Chinese, Portuguese, Samoan, Tamil, Kiswahili or Malay.

    Closing: No.1. Prize: £ 5,000. Entry Fee: £ 25.

    Southword Fiction Chapbook Competition

    To enter this international contest from the Munster Literature Centre in Cork, Ireland you should submit 10,000 to 15,000 words of fiction in the form of a collection of short stories. Stories can have been published previously in web or print journals, but not in a stand-alone publication by the author.

    Closing: Oct.31. Prizes: Best International Entry and Best Irish Entry. Entry Fee: £ 5 for one, £ 10 for six.

Blameless

    I was a freshman in college when I met the Whites. They were completely different from my own family, yet I felt at home with them immediately. Jane White and I became friends at school, and her family welcomed me like a long-lost cousin.

    In my family, it was always important to place blame when anything bad happened.

    "Who did this?" my mother would scream about a dirty kitchen.

    "This is all your fault, Katharine," my father would insist when the cat got out or the dishwasher broke.

    From the time we were little, my sister, brothers and I told on each other. We set a place for blame at the dinner table.

    But the Whites didn't worry about who had done what. They picked up the pieces and moved on with their lives. The beauty of this was driven home to me the summer Jane died.

    In July, the White sisters and I decided to take a car trip from their home in Florida to New York. The two older sisters, Sarah and Jane, were college students, and the youngest, Amy, had recently turned sixteen. Proud of having a new driver's license, Amy was excited about practicing her driving on the trip. She showed off her license to everyone she met.

    The big sisters shared the driving of Sarah's new car during the first part of the trip, but when they reached less crowded areas, they let Amy take over. Somewhere in South Carolina, we pulled off the highway to eat. After lunch, Amy got behind the wheel. She came to a crossroads with a stop sign. Whether she was nervous or just didn't see the sign no one would ever know, but Amy continued into the crossroads without stopping. The driver of a large truck, unable to stop in time, ran into our car.

    Jane was killed immediately.

    I was slightly injured. The most difficult thing that I've ever done was to call the Whites to tell them about the accident and that Jane had died. Painful as it was for me to lose a good friend, I knew that it was far worse for them to lose a child.

    When Mr. and Mrs. White arrived at the hospital, they found their two daughters sharing a room. Sarah had a few cuts on the head; Amy's leg was broken. They hugged us all and cried tears of sadness and of joy at seeing their daughters. They wiped away the girls' tears and made a few jokes at Amy as she learned to use her crutches(拐杖).

    To both of their daughters, and especially to Amy, over and over they simply said, "We're so glad that you're alive."

    I was astonished. No blame. No accusations.

    Later, I asked the Whites why they never talked about the fact that Amy was driving and had run a stop sign.

    Mrs. White said, "Jane's gone, and we miss her terribly. Nothing we say or do will ever bring her back. But Amy has her whole life ahead of her. How can she lead a full and happy life if she feels we blame her for her sister's death? "

    They were right. Amy graduated from the University of California and got married several years ago. She works as a teacher of learning-disabled students. She's also a mother of two little girls of her own, the oldest named Jane.