Every man wants his son to be somewhat of a clone, not in features but in footsteps. As he grows you also age, and your ambitions become more unachievable. You begin to realize that your boy, in your footsteps, could probably accomplish what you hoped for. But footsteps can be muddied and they can go off in different directions.

My son Jody has hated school since day one in kindergarten. Science projects waited until the last moment. Book reports weren't written until the final threat.

I've been a newspaperman all my adult life. My daughter is a university graduate working toward her master's degree in English. But Jody? When he entered the tenth grade he became a “vo-tech” student(技校学生). They're called “motorheads” by the rest of the student body.

When a secretary in my office first called him “motorhead”, I was shocked. “Hey, he's a good kid,” I wanted to say. “And smart, really.”

I learned later that motorheads are, indeed, different. They usually have dirty hands and wear dirty work clothes. And they don't often make school honor rolls(光荣榜).

But being the parent of a motorhead is itself an experience in education. We who labor in clean shirts in offices don't have the abilities that motorheads have. I began to learn this when I had my car crashed. The cost to repair it was estimated at $800. “Hey, I can fix it,” said Jody. I doubted it, but let him go ahead, for I had nothing to lose.

      My son, with other motorheads, fixed the car. They got parts(零件）from a junkyard, non-toasting toaster have been fixed. Neighbours and co-workers trust their car repair to him.a

        Since that first repair job, a broken air-conditioner, a non-functioning washer and a non-toasting toaster have been fixed. Neighbors and co-workers trust their car repairs to him.

        These kids are happiest when doing repairs. They joke and laugh and are living in their own relaxed world. And their minds are bright despite their dirty hands and clothes.

I have learned a lot from my motorhead: publishers need printers, engineers need mechanics, and architects need builders. Most important, I have learned that fathers don't need clones in footsteps or anywhere else.

        My son may never make the school honor roll. But he made mine.

    The hemlock(铁杉) trees along the Wappinger Creek, New York, look healthy. However, scientist Gary Lovett says the white balls which provide protection for the bugs are created by a tiny insect. It's hard to believe the tiny bug could kill a tree. However, trees can end up with millions and millions of the pests. When there are that many, it ends up killing the tree.

    The bug from East Asia is slowly killing trees across the USA. The trouble-making bug is just one of many invasive(入侵的) pests that have slipped into the United States. They can hurt other living things in their new home.

    Many invasive pests arrive on wooden pallets(运货板) piled inside shipping containers. They support and separate goods, and keep them from sliding around. Invasive pests often tunnel into the pallets. How can we stop pests from riding on pallets? Lovett says new rules are needed. The companies that make pallets don't want more rules. Congress has added an amendment(修正案) in the 2018 Farm Bill to try and prevent this problem. However, Lovett is not hopeful it will make much of a difference. Pallets are checked by inspectors. Many are sprayed with bug-killing pesticide. "I believe in the system," said Brent McClendon, president of The National Wooden Pallet and Container Association. He also said shipping containers are checked very carefully.

    Still, each year 13 million containers are shipped to the U. S. Each is full of wooden pallets. Lovett says: "Inspectors can't possibly check everything. All it takes are a few bad pallets; we should get rid of wooden pallets." He believes pallets should be made of plastic or eco-composite wood. Eco-composite wood is a mix of wood fiber and plastic. Insects cannot hide into it. One problem is that these choices cost more. They may be worth the extra money, though. Invasive pests cost the U.S. $5 billion a year. Trees don't just die in forests. They also die in cities and our yards. Then, they need to be replaced. That costs money, too.

    While elephants born without tusks (长牙)are not unheard of，they normally form just 2 to 6 percent of the population. However, that is not the case at Mozambique's Gorongosa National Park, where an astonishing 33 percent of female elephants born after the country's civil war ended in 1992 are tuskless. While that may appear to be just a coincidence, Joyce Poole, an elephant behavior expert, has another theory. The researcher thinks we may be witnessing unnatural evolution of the species due to the constant hunting of elephants for valuable ivory.

    Poole says before the country's 15-year-long civil war, the 100,000-acre park was home to over 4,000 elephants. However, by the time the conflict ended in 1992, about 90 percent of them had been killed for ivory to help finance weapons (武器)and meat to feed the soldiers. Of the less than 200 survivors, over 50 percent of adult females had no tusks. Therefore, it is not surprising that the park's tuskless elephant population has grown greatly.

    This is not the first time researchers have observed a great change in the population of elephants. At Zambia's South Luangwa National Park and Lupande Game Management Area， areas which were heavily hunted in the 1970s and 1980s, 35% of elephants 25 years or older and 13% of those younger than 25 are now without tusks. A 2008 study published found that the number of tuskless females at the Ruaha National Park in Tanzania went from 10.5 percent in 1969 to almost 40 percent in 1989, largely due to illegal hunting for ivory.

    The recent ban on ivory in both the US and China should help get rid of, or at least reduce, elephant hunting. However, scientists are not sure how long it will take for elephants with a higher rate of tuskless females, to change the trend.

    We all need to eat. So, meals could be a chance to stop what we're doing and spend time with the people in our lives. A recent study from a team of South Korea suggests that eating together has many good effects on children and teenagers while frequently eating alone may lead to poor eating habits and poor food choices. People who eat alone more than twice a week have a greater risk of developing high blood pressure.

    There are benefits of family dinners on children and teenagers.

    In 2014, the Organization for Economic Cooperation and Development (OECD) looked at data from nearly three-quarters of the world's countries. Among its findings is the fact that students who share a main meal with their families are less likely to hate school. Children who eat a main meal with their families are also less likely to take drugs (毒品).

    In the report, titled "The Importance of Family Dinners (VIII)," researchers say that teens who have frequent family dinners are more likely to say their parents know a lot about what's going on in their lives.

    Another study from the University of Montreal finds that children who eat with their families experience long-term physical and mental health benefits. These children are physically in better shape and drink fewer sugary soft drinks. These children also seem to have better social skills and are less violent.

    One of the researchers, Pagane, involved in this study is a professor at the university. She says that mealtimes with parents possibly provide young children with firsthand social events, which helps them have better communication skills.

    When an ice cube melts, it creates a puddle (水坑). When an ice sheet (冰盖)melts, it raises sea levels. It sounds simple, but scientists have debated for decades whether both the Antarctic and Greenland ice sheets actually were shrinking, and how much that melting contributed to rising sea levels.

    Now, a new study has provided the best evidence of how the polar ice sheets are responding to our warming world. In the study, an international team of scientists looked at 20 years of' data in the ice sheets collected by 10 satellite missions. The team's conclusion: The Greenland and Antarctic ice sheets both are losing ice overall. The researchers also found that between 1992 and 2011, melt water from those shrinking ice sheets caused sea levels to rise by about 11 millimeters.

    Over the 19 years studied, the Greenland ice sheet lost 2.7 trillion metric tons of ice. The Antarctic ice sheet also shrank by about 1.3 trillion metric tons. Previously, some scientists disagreed whether the Antarctic sheet, the largest mass of ice in the world, was shrinking or growing or neither.

    While the Earth is warming overall, the effect of climate change varies from region to region. Over the last 15 years, for example, scientists have something disagreed over how climate change has affected the polar ice sheets. Many studies found that the sheets lost a lot of ice and that not enough snow fell on the sheets to compensate for the loss. But other studies found that the loss of ice was balanced by the gain in snowfall.

    Richard Alley, a glacier scientist at Penn State University, said that many of those studies looked at different areas, and over different time periods. In addition, the studies didn't all use the satellite data in the same way. Those differences made, it difficult to compare the results.

    The data in the new study matched time periods and areas. The study also combined measurements from kinds of satellites.

New research from the University of Portsmouth has shown a marked increase in shipping in the North East Atlantic. Scientists now warn that more monitoring is required to help protect sea life. 

Researchers at the University of Ponsmouth have discovered that rates (率)of shipping in the North East Atlantic area rose by 34 per cent in a five-year period. The research is the first detailed survey of shipping activity in the North East Atlantic. Researchers used data from over 530 million vessel(船)positions recorded by Automatic Identification System(AIS). They looked at the change in shipping between 2013 and 2017 across ten different vessel types. In total the study area covered 1.1 million km², including waters off Belgium, Denmark, France, Germany,Iceland, Ireland, The Netherlands, Norway, Portugal. Spain, and the UK. 

Lead author, James Robbins said:"This change is likely to put more pressure on the marine(海 洋的)environment, and may influence the protection of at-risk species. Renewed monitoring effort is needed to make sure that protective measures are enough to save species under threat in a changing environment. "

Some of the greatest shipping increases were found in areas close to the Spanish coast. The Espacio Marino de la Costa da Morte saw a rise of 413 percent in vessel activity. It is an area used to protect seabirds. 

Dr. Sarah Marley, Visiting Researcher at the University of Portsmouth, said:"Shipping is the most widespread human activity in our oceans, carrying a set of threats-from unnoticeable effects like underwater noise pollution to serious results when ships hit whales. "

Professor Alex Ford. from the University's Institute of Marine Sciences, said:"Given the well- documented effects that shipping can have on the marine environment, it is necessary that this situation continues to be monitored-particularly in areas used to protect vulnerable(脆弱的)species which may already be under pressure. "