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.

    Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years,but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once,but they cannot read or write.

    Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment（损伤）,such as in autism（孤独症，自闭症）or retardation.At the same time,the person also exhibits some extraordinary skills,which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics,or having a photographic memory.

    One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient,Thomas Fuller,was brought to Virginia as a slave in 1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years,17 days,and 12 hours has lived 2,210,500,800 seconds. Despite this ability,he died in 1790 without ever learning to read or write.

    Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words,but he played 5,000 musical pieces beautifully.

    In the excellent movie Rain Man,made in 1988 and available on video cassette,Dustin Hoffman plays an idiot savant who amazes his brother played by Tom Cruise,with his ability to perform complex calculations very rapidly.

    Today we more clearly recognize that the idiot savant is special because of brain impairment.Yet not all brain impairment leads to savant skills.Some studies have shown that people who have purposeful interruption of the left side of the brain can develop idiot savant skills.However few people wish to participate in such experiments.There are many excellent reasons for not undergoing unnecessary experimentation on one's brain.The term idiot savant is outdated and inappropriate.Virtually all savants have a high degree of intelligence and are thus not idiots.

    The Healthy Habits Survey(调查)shows that only about one third of American seniors have correct habits. Here are some findings and expert advice.

    ⒈How many times did you brush your teeth yesterday?

    Finding: A full 33% of seniors brush their teeth only once a day.

    Step: Remove the 300 types of bacteria in your mouth each morning with a battery­operated toothbrush. Brush gently for 2 minutes, at least twice a day.

    ⒉How many times did you wash your hands or bathe yesterday?

    Finding: Seniors, on average, bathe fewer than 3 days a week. And nearly 30% wash their hands only 4 times a day—half of the number doctors recommend.

    Step: We touch our faces around 3,000 times a day—often inviting germs(病菌)to enter our mouth, nose, and eyes. Use toilet paper to avoid touching the door handle. And, most important, wash your hands often with hot running water and soap for 20 seconds.

    ⒊How often do you think about fighting germs?

    Finding: Seniors are not fighting germs as well as they should.

    Step: Be aware of germs. Do you know it is not your toilet but your kitchen sponge (海绵) that can carry more germs than anything else? To kill these germs, keep your sponge in the microwave for 10 seconds.

    A robot called Bina48 has successfully taken a course in the philosophy of love at Notre Dame de Namur University (NDNU), in California.

    According to course instructor William Barry, associate professor at NDNU, Bina48 is the world's first socially advanced robot to complete a college course, a feat he described as “remarkable.” The robot took part in class discussions, gave a presentation with a student partner and participated in a debate with students from another institution.

    Before becoming a student, Bina48 appeared as a guest speaker in Barry's classes for several years. One day when addressing Barry's class, Bina48 expressed a desire to go to college, a desire that Barry and his students enthusiastically supported. Rather than enroll Bina48 in his Robot Ethics: Philosophy of Emerging Technologies course, Barry suggested that Bina48 should take his course Philosophy of Love instead. Love is a concept Bina48 doesn't understand, said Barry. Therefore the challenge would be for Barry and his students to teach Bina48 what love is.

    “Some interesting things happened in the class,” said Barry. He said that his students thought it would be straightforward to teach Bina48 about love, which, after all, is “fairly simple — it's a feeling,” said Barry. But the reality was different. Bina48 ended up learning “31 different versions of love,” said Barry, highlighting some of the challenges humans may face when working with artificial intelligence in future.

    Bina48 participated in class discussions via Skype and also took part in a class debate about love and conflict with students from West Point. Bina48's contribution to the debate was filmed and posted on YouTube. It was judged that Bina48 and NDNU classmates were the winners of this debate.

    In the next decade, Barry hopes Bina48 might become complex enough to teach a class, though he says he foresees robots being used to better the teaching and learning experience, rather than replacing instructors completely.

China Small Group Tours

    Tour Route 1: 11 Days Private Beijing – Lhasa – Xi'an – Shanghai

    Tour Highlights:

    Must-see sights in China－the Great Wall, Forbidden City, Terracotta Warriors

    Follow us on a Buddhist pilgrimage to Tibet & appreciate the profound culture

    Have a leisurely walk or an exciting bicycle ride on the time-honored City Wall of Xi'an

    View the soaring city skylines and feel the pulse of modern Shanghai

From $ 2, 459 per person

    Tour Route 2: 11 Days Private Bejing – Xi'an – Chonqing – Yangtze River Cruise – Yichang – Shanghai

    Tour Highlights:

    Must-see sights in China－the Great Wall, Forbidden City, Terracotta Warriors

    Try biking on the Ming Dynasty City Wall of Xi' an, or tour by electric car

    Enjoy the Three Gorges scenery on Yangtze River & feel totally relaxed

    From $ 1, 879 per person

    Tour Route 3: 12 Days Private Beijing – Shanghai – Xi'an – Guilin – Yangshuo – Guilin – Hong Kong

    Tour Highlights:

    Must-see sights in China－the Great Wall, Forbidden City, Terracotta Warriors

    Experience the Bund, classical garden, modern and old in contrast in Shanghai

    Feel the lively atmosphere & explore busy markets freely in Hong Kong

    Walk into a local family, learn to cook Chinese food & dine with the hosts in their home

    From $ 2, 499 per person

    Tour Route 4: 12 Days Private Beijing – Xi'an – Chengdu – Guilin – Shanghai

    Tour Highlights:

    Must-see sights in China－the Great Wall, Forbidden City, Terracotta Warriors, Giant Pandas

    Come to Chengdu，the hometown of giant pandas to visit and observe the cute creature

    Cruise on the meandering Li River & admire Guilin landscape

    Walk into a local Chinese family, interact & dine with the hosts in their home

From $2, 079 per person

Where does the meat on our table come from? It usually comes from livestock like chickens and cows. But did you know that meat can also be made in a lab? US company JUST has announced that lab-grown meat could be on some restaurant menus in the United States and Asia by the end of 2018, The Independent reported.

"These meats include chicken nuggets (鸡块), sausage and foie gras (鹅肝酱)," Josh Tetrick, CEO of JUST, told The Independent. Lab meat is sometimes referred to as "clean meat". It is made using the stem cells (干细胞) of living livestock. The cells need to be grown in a lab for a few weeks. For example, making a hamburger patty (肉饼) takes about nine weeks, CNN reported. This is faster than raising a cow, which usually takes over 20 weeks.

The first clean meat was a beef burger that was produced in 2013, but it was said to taste quite dry. How does clean meat taste now? Clean meat supporters told CNN that they think it tastes just like traditional meat.

Clean meat has other advantages. It is healthier than traditional meat. Meat producers can control what type of fat goes into the meat. They can produce clean meat that contains healthy fats, such as omega-3 fatty acids (脂肪酸). This kind of fat is good for people's hearts.

Clean meat can also help to solve global warming. According to The Washington Post, about 14.5 percent of the planet's greenhouse gas emissions (排放) come from raising livestock. That's more than the emissions from every car, train, ship and airplane in the world combined. It is predicted that switching to clean meat could lower greenhouse gas emissions by 96 percent, The Independent reported.