Many early domestic (驯养的) dogs ate almost no meat. Dogs living around 3000 years ago in what is now Spain were instead fed cereals, such as millet (小米), by their owners.
Although the diet may reflect the fact that meat was relatively in lack among human societies at the time, feeding dogs with cereals could have been advantageous, says Silvia Albizuri at the University of Barcelona in Spain. It may have been a way to ensure the dogs had plenty of energy for the hard work of herding and guarding livestock (牧群), she says, particularly since these dogs “were not pets as we think of them nowadays”. Albizuri and her colleagues studied the remains of 36 dogs from Can Roqueta, an archaeological site near Barcelona. It lies on a plain near the coast and was inhabited from the Stone Age onwards. The dogs lived in the Bronze Age and Iron Age, between 1300 and 550 BC, and had been buried in pits. The researchers obtained protein from the dogs’ bones and focused on the carbon in the samples, which give an indication of what the animals ate.
The dogs’ diets differed considerably. While nine of them ate plenty of meat and 10 were omnivorous (杂食的), the rest ate mostly plants.
The finding adds to the evidence that many early domestic dogs ate little meat, says Albizuri. This trend is thought to have begun with the start of farming. “When human societies began to domesticate plants during the Neolithic period, hunting decreased and the human diet was based mainly on vegetables,” she says. “Dogs began to be fed on plants, mainly cereals.”
1. What can we know from the second paragraph?| A．The early human beings had nothing to eat. |
| B．The early dogs did not like meat at all. |
| C．There was not enough meat for early humans. |
| D．Dogs were eaten by the early human beings. |
| A．Hunters. | B．Pets. | C．Food. | D．Friends. |
| A．Bones. | B．Plants. | C．Normal dinners. | D．Meat. |
| A．Human’s habit. | B．Dog’s development. |
| C．Productive forces. | D．Social customs. |
相似题推荐
【推荐1】Somewhere in the highlands of Afghanistan, a hungry fox pounces （猛扑）on a tasty-looking leopard gecko （豹纹 壁虎）.But the lizard has a get — out — of — jail — free card: a separable tail. The dropped part waves in an energetic but uncontrolled way around long enough to distract the fox, allowing the gecko itself to run off and hide.
Leopard geckos are one of a few lizard species that possess this ability, known as autotomy （自切）.The technique is effective, but the tail can account for about a quarter of the lizard's body mass. So how do these animals adapt to losing so much of it that quickly?
When geckos lose their tail, they "take this more sprawled posture （四肢伸开的姿势）"and walk with their limbs spread out farther from their body, says Chapman University biologist Kevin Jagnandan. Most researchers initially assumed this posture was a response to a suddenly shifted center of mass. But when Jagnandan observed leopard geckos with a tail in his laboratory, he realized that they wag it as they walk, suggesting that these movements may be key to the lizards' movements.
To test this assumption, Jagnandan and his team assessed the postures of 10 geckos walking in various conditions: with their tail intact （完整的）；with their tail restricted by a small section of glued-on fishing rod （whose mass can be neglected）; and with their tail self-amputated. These comparisons allowed the researchers to distinguish the effects of lost mass from those of lost tail-wagging on the geckos’ movements.
The lizards with an immobilized tail adopted ways similar to those with no tail, the researchers reported in a study published in Scientific Reports. This result suggests the sprawling walk they adopt after losing their tail is not compensating for the missing mass but rather for the lack of tail-wagging. Jagnandan thinks tail movements help the lizards keep balance and stability as they walk. He suspects that the tails of mammals living in trees, such as cats and monkeys, serve a similar purpose.
Bill Ryerson, a biologist at Saint Anselm College, who was not involved in the study, was surprised by the findings. "We thought we had settled it ——it seemed pretty open-and-shut" that mass was the main factor, he says. The new study challenges this earlier idea in a "beautifully simple" way, Ryerson adds.
Jagnandan hopes that understanding how animals react to missing body parts could ultimately help engineers design robots that can move more efficiently as heavy loads — or even entire limbs --- are added and removed.
1. From the first two paragraphs we can learn that ______.| A．the fox likes to play with the gecko's tail |
| B．the fox falls for the trick of the gecko |
| C．moving without a tail is much tougher for the gecko |
| D．the gecko becomes inactive when losing its tail |
| A．the posture was key to their movements |
| B．their center of mass had changed |
| C．the posture was their unique survival skill |
| D．they imitated other mammals' behavior |
| A．They are in accordance with the expectation of Bill Ryerson. |
| B．They were obtained after researchers compared three geckos' movements. |
| C．They solved several mysteries concerning other mammals. |
| D．They can be applied to the field of artificial intelligence. |
| A．Why leopard geckos prefer a habitat in the highlands. |
| B．How leopard geckos play hide and seek games. |
| C．How leopard geckos adapt to losing their tails. |
| D．What role tails play in leopard geckos' life. |
【推荐2】Nothing feels more like summer than a neighborhood barbecue. But the annoyance of summer gatherings remains: the buzzing(嗡嗡声) of mosquitoes around our ears.
“The buzzing in your ear is mostly just a side effect of the mosquito's wings beating,” said Michael Riehle, a professor at the University of Arizona. “The sound doesn't have a long range, so you notice it most when they are flying around your ears.”
“From a distance, mosquitoes track carbon dioxide that we give out.” Riehle told Live Science. “They fly back and forth to follow that concentration level back to the source.”
But in fact, that buzzing you hear is likely from a female mosquito. That's because male and female mosquitoes lead very different lives. The males typically hang out and feed on the sweetest part of flowers; they couldn't care less about the humans wandering about. The females, however, need to find a blood meal in order to have enough energy to produce eggs.
As she approaches, the female mosquito zeros in on body heat and the carbon dioxide to land on the victim. The female mosquito uses taste sensors on her feet to determine whether the human, or any blood-bearing animal, is adequate to tap for her next meal.
But while we feel mosquitoes buzzing around our ears, Riehle noted that most mosquitoes are not attracted to our heads. Rather, these bloodsuckers may be more likely to seek out our feet, which have bacteria that give off attractive smell to mosquitoes. However, most people probably don't notice a mosquito buzzing around their ankles, he said.
Another study found that female mosquitoes were more attracted to men who had less diverse bacteria on their skin than to men with more diverse skin bacteria; these bloodsuckers also prefer those who wear dark colors, such as black.
1. What attracts mosquitoes to our head?| A．There is most carbon dioxide. | B．The face skin is easy to stick in. |
| C．There exists their favorite smell. | D．They can suck most blood there. |
| A．Her nose. | B．Her sensors. | C．Her eyes. | D．Her ears. |
| A．Black. | B．Blue. | C．White. | D．Red. |
| A．Why do mosquitoes buzz in our ears? |
| B．How can we avoid the buzzing of mosquitoes? |
| C．How are male and female mosquitoes different? |
| D．What effect does the buzzing of mosquitoes have? |
Experts estimate that one out of every five fish sold was caught illegally. It threatens(威胁) food security and hurts the environment. Officials are using new observational technology to fight illegal fishing.
“Thank you for taking the time to join us here in Harwell (UK) in the Operations Center to what we call ‘Project Eyes on the Seas.’” says Tony Long, who leads the Ending Illegal Fishing program for Pew Charitable Trusts. The group created Project Eyes on the Seas. Large three-dimensional images of a globe can be seen on a video.
“It looks different from what you might expect because this globe only shows you the boats that are coming into this system from a live automated information system or AIS.”
The screen shows 120,000 fishing boats have AIS. They are required to have the technology. But those who are fishing illegally often turn it off. The technology does not tell observers when that happens. Project Eyes on the Seas combines satellite information with secret government records on every ship’s past activities.
Mr. Long says that permits researchers to understand exactly where the fishing boats are operating. The Pew team gives the information it gathers to port officials to help them decide if they should take action against a ship. Tony Long says he would like to be able to provide port officials all over the world with clear lists. They would inform the officials about ships to inspect, ships to bar from entrance, and ships to permit entrance for trade activities.
The Pacific island nation of Palau was an early user of the technology. Palau has one of the richest fishing areas in the world. Last year, it announced a plan to ban commercial fishing in a 630,000 square kilometer area. K.B. Sakuma is a special adviser to the president of Palau. He says Palau is trying to deal with a recent increase in illegal, unsupervised（无人监管的）and unreported fishing.
“And
1. According to the estimation, what is the percentage of illegal fishing?
| A．1% | B．5% | C．23.5% | D．20% |
| A．leave written records for the country only |
| B．help fishermen to catch more fish on the Seas |
| C．prevent all of the fishing practices on the Seas |
| D．assist port officials in deciding whether to ban a ship from fishing |
| A．The clear lists. |
| B．The investigators. |
| C．The fishing boats. |
| D．The Project Eyes. |
| A．The issue is urgent. |
| B．The problem begins to appear. |
| C．The number of fishermen is increasing. |
| D．The head of the fishermen is coming. |
| A．When the fishermen turn off the AIS, the inspector will know the situation. |
| B．The special adviser to the president of Palau leads the Ending Illegal Fishingprogram. |
| C．The new technology contributes to solving the problem of illegal fishing. |
| D．Commercial fishing is permitted in Palau. |
【推荐1】To most Americans ---- and probably most Westerners --- romantic love is the greatest love of all. In fact, romantic love sometimes considered the very definition of love. We often use “love” as shorthand for romantic love, just as we use the word “relationship” without even thinking that we need to point out that we mean “romantic relationship”.
Before I started studying single life, I had no idea why contemporary American views of love were so narrow. Then I spent a long time reading.
When I wrote Single Out, I summarized some of what I learned this way:
From Middle Ages through early modern times, to describe the love for a spouse(配偶) as the greatest love of all would have been sacrilegious. The most special place in anyone’s heart was supposed to be reserved for God. Over the years, many kinds of people and entitles (独立存在物) have been considered deserving of love and affection. They have included spiritual figures and ancestors, immediate and extended family, friends and communities.
As Stephanie Coontz, author of a fascinating book Marriage A History, noted, during 1800s, Westerners believed that love developed slowly out of admiration, respect, and appreciation; therefore, the love one felt for a sweetheart was not seen as qualitatively different from the feeling one might have for a sister , a friend, or even an idea.
The ruling American worldview may well represent one of the narrowest explanations of love ever imagined. Where once the definition of love and affection reached out to family, friends and communities, reached back to ancestors, and reached up to the heavens, now they surround and squeeze just one other person --- sometimes to the point of asphyxiation(窒息).
Is any of this changing? Maybe. More and more people are living single. Those people who do marry are, on the average, getting around to it later in life than ever before. Americans spend more years of their adult lives not married than married. One potential hint of these big changes is that we will start recognizing how much other kinds of people and pursuits matter to us. We may realize, for example, that a life filled with close friendships is a life filled with love. Those of us who are fortunate enough to take and fulfill jobs may feel freer to say that we love our work. And if we are single, maybe we will be able to do so with less risk of being dismissed as using our work as compensation for not having a spouse.
1. What does the text mainly indicate?| A．The hint of love changes these days. |
| B．Love used to mean so much more. |
| C．Love all instead of only your spouse. |
| D．Which is better, to marry or to be single? |
| A．Poor. |
| B．Ridiculous. |
| C．Showing a great respect for love. |
| D．Showing a lack of respect for God. |
| A．Romantic love doesn’t always come ahead of other loves. |
| B．Coontz thinks all kinds of loves come from appreciation. |
| C．That love develops slowly is popular in American society. |
| D．Americans’ view of love today is only an imagination. |
| A．More and more Americans want to be single. |
| B．More and more Americans tend to delay marriage. |
| C．There are many people who want work instead of marriage. |
| D．There are so many ways that our lives can be filled with love. |
【推荐2】Scientists are excited by the rediscovery of the giant lacewing. It is an insect which looks like a cross between a fly and a moth. It has spotted wings with a span of roughly 50 millimeters, holding the wings over its body like a tent.
Giant lacewings have been around since the Jurassic era, a period of time about 150 to 200 million years ago. In the 1950s, scientists thought giant lacewings had disappeared from eastern North America. However, scientists recently confirmed that one had been spotted.
Michael Skvarla works for Penn State University, who is the director of its insect identification lab. Skvarla found the giant lacewing in 2012. He remembers it clearly, “I was walking into Walmart to get milk and I saw this huge insect on the side of the building,” Skvarla said. “I thought it looked interesting, so I put it in my hand and did the rest of my shopping with it between my fingers. I got home, mounted it and promptly forgot about it for almost a decade.”
Then, in late 2020, Skvarla was teaching biodiversity in a Zoom class during the pandemic lockdown. During the class, Skvarla showed his students microscopic images of the insect he had seen at Walmart. Together, they stared at the images. They studied the insect closely. Then, they realized that the insect had been wrongly labeled. Many scientists are stirred by this discovery. Now they have started wondering if there may be entire populations hiding out, which requires for further investigation.
And the causes of the supposed disappearance of the insect have long been a mystery. With a deeper research, there are some possible explanations. One is light pollution, which is the brightening of the night sky from man-made light sources such as street lights. Light pollution can disrupt the natural cycles of living things. Another cause could be the introduction of non-native insects such as ground beetles. They can cause harm to the environment. Ground beetles prey on giant lacewings. People’s stopping forest fires may also play a part in the disappearance of the lacewing. This is because giant lacewings need ecosystems that rely on natural fires.
1. What can we know about the appearance of the giant lacewing?| A．It looks like a mix of a fly and a moth. |
| B．Its body length is about 50 millimeters. |
| C．Its wings are tiny and rough. |
| D．Its body shape is like a tent. |
| A．The researcher accurately recognized it at first sight. |
| B．It was spotted at Walmart during the pandemic. |
| C．It had been incorrectly labeled initially. |
| D．Researchers closely studied the insect for nearly a decade. |
| A．The lengthening of natural sunlight time. |
| B．The increase in the number of native attackers. |
| C．The frequent occurrence of forest fires. |
| D．The biological rhythms were messed up by man-made light. |
| A．A biology magazine. | B．A science fiction. |
| C．A research plan. | D．A medical report. |
【推荐3】Over the past few months huge groups of locusts(蝗虫), one of which occupied an area more than three times the size of New York City, have eaten up crops across the Home of Africa and the Middle East, leaving an estimated 20 million people at risk of famine(饥荒). The first generation's eggs are starting to hatch, and now even bigger swarms(虫群) are forming threatening. Countries from the Democratic Republic of Congo to Yemen, Iran, Pakistan and India, “representing a threat to food security and livelihoods,” says the U.N.'s Food and Agriculture Organization(FAO).
Desert locusts' populations explode when weather conditions are right. That explosion can create huge swarms that can travel great distance-more than 90 miles in a day-in search of food. Warm weather and unusually heavy rains in the Horn of Africa at the end of 2019 provided the moist(湿润的) soil necessary for hatching eggs. From there, the insects spread rapidly, resulting in one of the worst outbreaks the region has seen in more than 70 years.
A typical swarm numbering 4 billion to 8 billion locusts, can consume in one day the same amount of food as 35 million people. Some swarms have been so thick in parts of Kenya that they have prevented planes from taking off. Governments have used widespread aerial spraying of pesticides when available; in poorer regions, where aircraft are unavailable, soldiers battle the swarms with handheld spray pump.
The FAO has appealed for $138 million to support affected communities, If the locusts are not stopped before the next generation hatches, the impact could be terrible: the FAO guesses that an additional 25 million people across the region could lose their crops. Scientists in Kenya hope a new computer-assisted tracking program that combines satellite data with weather-mapping software will help predict the swarms next destination, buying-regional authorities enough time to prepare a response. Buy coronavirus- related travel restriction have delayed relief efforts as well as response mechanisms. The locusts have no such travel limitations.
1. The author uses many statistics in the passage to show_____| A．the disastrous consequence of the outbreaks of locusts |
| B．the serious conditions facing the New York City |
| C．the speed of swarms of locusts travelling |
| D．the exact number of crops consumed by locusts |
| A．The great distances locusts can travel. |
| B．The explosion of locusts' population. |
| C．The perfect conditions for hatching their eggs. |
| D．The result of the unusual outbreaks of locusts. |
| A．The travel restrictions may probably worsen the urgent situation. |
| B．It is unlikely to predict the swarms' next destination now. |
| C．A lot of money has been raised after the FAO's appeal |
| D．It's not difficult for humans to win the battle against the locust |
