An individual from an unknown hominid (原始人类) species walked across a field of wet, volcanic ash in what is now East Africa around 3.66 million years ago, leaving behind a handful of footprints.
Those five ancient footprints, largely ignored since they were partly unearthed at Tanzania’s Laetoli site in 1976, show features of upright walking by a hominid, a new study finds. Researchers had previously considered them hard to classify, possibly produced by a young bear that took a few steps while standing. But the latest analysis refutes that suggestion.
McNutt, DeSilva, who started the new investigation as a Dartmouth College graduate student, and their colleagues fully dug out and cleaned the five Laetoli footprints in June 2019. Then they measured, photographed and 3-D scanned the ancient tracks. McNutt’s group focused on two footprints that were particularly well-preserved. Foot shapes, sizes, and walking characteristics of the Laetoli individual differed in various ways from those of other hominid individuals at the same site. The prints also didn’t match those from modern black bears and modern chimps (黑猩猩) walking upright.
The Laetoli individual possessed a wider, more chimplike foot than humans, the researchers say. Its big toe stuck out slightly from the second toe (脚趾), but not to the degree observed in chimps. On one step, the Laetoli individual’s left leg crossed in front of the right leg, leaving a left footprint directly in front of the previous track. People may cross-step in this way when trying to regain balance. And bears and chimps assume a relatively wide standing due to knee and other bone arrangements that prevent them from walking like the Laetoli individual and probably from cross-stepping, the scientists say.
Given that only two of the ancient footprints are complete enough to analyze thoroughly, the possibility that a chimp other than a hominid made the Laetoli footprints can’t be ruled out, says William Harcourt-Smith, a scientist at Lehman College. But evidence of cross-stepping is enough to prove that it was a hominid track maker, he says.
1. What does the underlined word “refutes” in Paragraph 2 mean?| A．Objects to. | B．Supports. | C．Puts forward. | D．Criticizes. |
| A．They are less chimplike. | B．They have toes sticking out. |
| C．They show a wider standing. | D．They get features of cross-stepping. |
| A．Challenging. | B．Convincing. |
| C．Confusing. | D．Conflicting. |
| A．To share a new discovery. | B．To describe a major event. |
| C．To settle a huge disagreement. | D．To introduce an unknown species. |
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【推荐1】Heritage sites of outstanding and universal value located along the African coast are at threat of rising sea levels, and increased climate change adaptation is urgently needed for the protection of the heritage sites, according to research.
The research, published last week by the University of Cape Town’s African Climate and Development Initiative, indicated that more heritage areas are exposed to flooding compared with erosion. Findings showed that 56 of 284 identified African heritage sites are at risk of a 100-year coastal extreme event. Furthermore, the researchers project the number of exposed sites to more than triple by 2050.
Michalis Vousdoukas, scientific officer at the European Commission and lead author of the report, said the Loss of forts and castles along the coast would have strong consequences not only for the people living in their neighborhood, but also the international community. He said many of the sites are deeply connected with peoples’ identity and tradition, and they are essential for social well-being, safe-guarding traditional knowledge and livelihoods.
The research findings highlight the urgent need for increased climate change adaptation for heritage sites in Africa, including governance and management approaches, site-specific vulnerability assessments, exposure monitoring and protection strategies. The findings also indicated that reducing greenhouse gas emissions would result in a 21 percent reduction of the median exposed area, as well as 25 percent fewer sites that would be highly exposed by the end of the century.
The National Museums of Kenya, a state corporation that manages cultural and natural heritage, is working with communities to conserve sites that are threatened by coastal flooding and erosion. Fatma Twahir, the chief curator (负责人) of heritage site Fort Jesus in Kenya’s coastal Mombasa city, told Kenya News Agency that the National Museums of Kenya has partnered with the cultural protection fund to train curators and communities living near the heritage sites to keep them safe.
1. What does the underlined word “event” refer to in the context?| A．the natural disaster | B．the loss of forts and castles |
| C．the international support | D．the environment adaptation measures |
| A．Those forts and castles are of great economic value in terms of tourism. |
| B．The loss of those sites would conceal the identity of the people living nearby. |
| C．If the sites got damaged, the whole world would be influenced as well as the local. |
| D．The protection of those sites is necessary for the safety of the whole continent. |
| A．Monitoring all the heritage sites. |
| B．Reducing greenhouse gas emissions. |
| C．Assessing the short-term climate change. |
| D．Developing new methods of governing their countries. |
【推荐2】“Preventing obesity and smoking can save lives, but it doesn’t save money,”reported researchers. “ It was a small surprise, for it is against the common belief,” said Pieter van Baal, who led the study. “But it makes sense. If you live longer, then your costs of the health system will be more.”
The researchers found that from age 20 to 56, fat people had the most expensive health costs. But on average, healthy people lived 84 years. Smokers lived about 77 years, and fat people about 80 years. Smokers and fat people tended to have more heart disease than healthy people. Therefore, in the long run, the thin and healthy group spent about $417,000, from age 20 on. Smokers spent about $ 326,000 and fat people $371,000.
“The result throws a bucket of cold water onto the idea, based on guesswork, that obesity is going to cost trillions of dollars,” said Patrick Basham, a professor of health politics. “If we’re going to worry about the future of obesity, we should stop worrying about its financial impact,” he said.
“The benefit of obesity prevention may not be seen immediately in terms of cost saving in tomorrow’s budget, but there are long-term gains,” said Baal. “These are often immeasurable when it comes to people living longer and healthier lives.” In the meanwhile, he said that governments should recognize that successful smoking and obesity prevention programs mean that people will have a higher chance of dying of something more expensive later in life.
“Lung cancer is a cheap disease to treat because people don’t survive very long. But if they are old enough to get Alzheimer’s(早年性痴呆症) one day, they may survive longer and cost more. We are not advising that governments stop trying to prevent obesity,” Baal said.” But they should do it for the right reasons.”
1. Among middle-aged people, whose costs of the health system is the most?| A．Those who are heavy smokers. |
| B．Those who are overweight. |
| C．Those who are too thin. |
| D．Those who are suffering from heart attacks. |
| A．It turns out to be innocent. |
| B．It comes from scientific studies. |
| C．It is based on medical evidence. |
| D．It has changed over the past years. |
| A．reducing the risk of suffering cancer |
| B．weakening obesity’s financial impact |
| C．making sure of people’s long and healthy life |
| D．reducing the money spent on medical programs |
| A．A Recent Medical Study Shows the Truth about Health |
| B．Preventing Obesity and Smoking May Cost More |
| C．Obesity and Smoking Lead to Expensive Diseases |
| D．Governments Change Attitude towards Obesity and Smoking |
【推荐3】Are you looking for a winter vacation destination? Try these four vacation lands and they will certainly give you an unforgettable experience.
Solitude Mountain, Utah
Solitude Mountain is a place often recommended by tourist agents. It’s a place to go if you love skiing in winter but hate waiting on lift lines. Loving a bargain doesn’t hurt either since the accommodations here are less expensive.
Key West, Florida
The crowds thin out and the prices fall in Key Westin winter. Key West has a remote and romantic feel. It has inspired many poets and literary greats. It will inspire you to literally celebrate the sunrise. Surely, there are nightly sunset celebrations!
Taos, New Mexico
Taos in New Mexico is a popular winter spot. Besides skiing, you’ll be able to experience all the cultures and sights, including the thousand-year-old Taos Pueblo, the only living native American community that is regarded as a World Heritage Site by UNESCO.
Big Sky, Montana
Big Sky in Montana has more than 5,800 acres of skiing area spreading across a few mountains, with a vertical drop of 4,350 feet, as well as 85 km of Nordic tracks. It’s a good idea to head for Big Sky for the fantastic skiing in winter because it has been called “the least crowded vacationland ever”.
If more information is needed, you can click here.
1. Which place will you prefer to visit if you want to cut down the traveling cost?| A．Solitude Mountain. | B．Key West. | C．Taos. | D．Big Sky. |
| A．Wait on lift lines. | B．Get close to an ancient community. |
| C．Literally celebrate the sunrise. | D．Visit the least crowded vacationland. |
| A．A magazine. | B．A textbook. | C．A website. | D．A guidebook. |
This Portuguese ship sank off the coast of Oman in 1503. First discovered in 1998 and then extensively excavated (发掘) by a team led by David Mearns between 2013 and 2015, it is the oldest shipwreck (沉船) recovered from Europe’s Age of Exploration.
Black Sea ShipwreckDiscovered in 2018 by a team from the Black Sea Maritime Archaeology Project, the ship sank more than 2,400 years ago. It is the oldest undamaged shipwreck ever found. “A ship in such good condition from the classical world, is something I would never have believed possible,” said Professor Jon Adams, the principal investigator of the team that found the wreck.
GribshundenThe flagship of John, King of Denmark, caught fire and sank in the Baltic Sea in 1495. There, it lay undiscovered until members of a local dive club came across it in the 1970s; unaware of its significance, they did not report it to archaeologists until 2000, and not until 2013 was the wreck’s identity confirmed. Considered one of the best-preserved shipwrecks of the period, it has slowly been revealing its secrets.
Black SwanIn May 2007, a Florida-based company announced that, using underwater robots, it had discovered a shipwreck in the Atlantic, code-named (代号为) “Black Swan”. However, the government of Spain claimed that the wreck was the Nuestra Senora de las Mercedes, a Spanish ship that sank off the coast of Portugal in 1804 following a battle with four British navy ships. After a long legal battle, the treasure was returned to Spain in 2012.
1. Which shipwreck is the latest discovery?| A．Esmeralda. | B．Black Sea Shipwreck. |
| C．Gribshunden. | D．Black Swan. |
| A．They were discovered in the same area. |
| B．They were first noticed by local people. |
| C．They were in good shape when discovered. |
| D．They were in the possession of a royal family. |
| A．By going to the court. |
| B．By contacting the Portugal government. |
| C．By joining a battle against British navy. |
| D．By offering another treasure as an exchange. |
【推荐2】A new four-legged whale species was recently discovered by a team of researchers in Egypt. The fossil which was encased in a tomb of rock dates back to over 43 million years ago!
This ancient creature had four functional legs, so it could dwell on both land and in water. Ironically, Egypt’s Fayum Depression, the desert where the fossil was discovered, was an ocean millions of years ago.
Researchers believe this fossil is an example from an era when land animals were adapting to marine life. Modern whales evolved from deer-like land mammals over the course of millions of years, and this unique whale could travel across land and swim in the ocean.
The new species is named Phiomicetus Anubis because the whale’s skull resembles the Egyptian jackal-headed god of death, Anubis. Scientists have also been able to recover the whale’s partial skeleton. They inferred that the ancient whale was about three meters in length and weighed 1,300 pounds. The mammal had a long mouthful of teeth, which indicated that it fed on smaller mammals and other sea life.
After analyzing the remains at Mansoura University in the Nile River Delta, scientists supposed that P. Anubis is the oldest semi-aquatic whale species found in Africa. Although the fossil itself was discovered thirteen years ago, researchers just completed the analysis and made the exciting announcement of a new species. Other whale fossils with legs have been found before, but the P. Anubis is the earliest, of its kind found in Africa.
1. Where did the researchers find the fossil?| A．In the India Ocean. | B．On the Rock Islands. |
| C．In the Fayum Depression. | D．In the Nile River Delta. |
| A．Its weight. | B．Its length. | C．Its teeth. | D．Its legs. |
| A．The study of Phiomicetus Anubis is time-consuming. |
| B．The analysis of Phiomicetus Anubis has a long way to go. |
| C．Phiomicetus Anubis is the oldest mammal found in Africa. |
| D．Phiomicetus Anubis is the world’s largest semi-aquatic whale species. |
【推荐3】Ninety years ago a man named Howard Carter made a great find. But he didn’t discover an unknown people group or a new plant. He found the resting place of a king.
People had seen signs of King Tutankhamun’s tomb (坟墓) but had never found it. Finally, Carter’s team discovered a set of steps that led down to some underground rooms. There Carter found the king’s body and many of his treasures.
Carter recorded his first impression in his popular book, The Tomb of Tut-Ankh-Amen:
At first I could see nothing, the hot air coming from the room causing the candle light to flicker (闪烁), but later, as my eyes grew used to the light, details of the room within appeared slowly and clearly, strange animals and gold — everywhere the light of gold... I was struck speechless with amazement, and when Lord Carnarvon, unable to stand the silence any longer, asked anxiously, “Can you see anything?” it was all I could do to get out the words, “Yes, wonderful things.”
The discovery has made King Tutankhamun, Tut for short, one of the best-remembered kings of Egypt. Tut became king when he was only 9 years old and ruled ancient Egypt from 1332 to 1323 B.C. No one is sure why, but he died suddenly before he turned 20. Because he died so young, there wasn’t time to prepare a great tomb for him. So he ended up with a smaller tomb. Its small size was actually the reason why it stayed hidden for so long. And, Tut’s tomb was not like other Egyptian kings’— it was not as damaged by time or robbers as other tombs. King Tut’s tomb remains the best-kept royal (皇室的) tomb ever discovered. The discovery of this little tomb has helped people learn a great deal about ancient Egypt.
1. We can learn from Paragraphs 1 and 2 that________.| A．Howard Carter found Tut’s tomb in the 1930s |
| B．there were a lot of treasures in Tut’s tomb |
| C．Howard Carter found Tut’s tomb by accident |
| D．a new plant was found in Tut’s tomb |
| A．Calm. | B．Proud. |
| C．Disappointed. | D．Shocked. |
| A．He died of a strange disease. | B．He ruled Egypt for about nine years. |
| C．He is known to few people today. | D．He built his own tomb over a long time. |
| A．King Tut’s story. | B．How to find a tomb. |
| C．Howard Carter’s achievement. | D．King Tut’s tomb. |
