1 . The green and red watermelon is a sweet, refreshing summer snack. But it wasn’t always so sugary or brightly colored. So what did watermelons originally taste and look like, and from where did they come?
The fruit isn’t from the Fertile Crescent of ancient Mesopotamia, as so many other domesticated (家养的) crops are, research shows. Susanne Renner, a scientist, and her colleagues carried out comprehensive genetic sequencing (基因测序) of the domesticated watermelons — the kind you might find on supermarket shelves — along with six wild watermelon species.
“We found the modern genomes (基因组) of the domesticated watermelon are more closely related to the Sudanese wild type than any other that we analyzed,” she said. The Sudanese wild watermelon has some obvious differences from the domesticated version. “The flesh is white and not very sweet, and it’s mainly used as animal feed,” Renner said. Nevertheless, the genetic similarity between the two species led the researchers to conclude that the Sudanese fruit is probably a precursor (前身) to the red and sweet domesticated watermelon.
It’s likely that ancient farmers grew non-bitter varieties of the wild watermelon and thus increased its sweetness over many generations through the domestication process. The red color is probably also thanks to artificial selection, in which farmers likely favored and selectively bred red fruit.
We already knew that the ancient Egyptian king Tutankhamun was buried with watermelon seeds 3,300 years ago, yet that isn’t sufficient proof of a domesticated, sweet watermelon. But then, Renner found an image of a watermelon-like fruit on an ancient Egyptian tomb painting, thought to be more than 4,300 years old. In a separate tomb, another image showed the watermelon cut up in a dish alongside other sweet fruits. This realization, coupled with Renner’s genetic findings, suggests that the watermelon was most likely domesticated around that time either in Egypt or within trading distance of the ancient empire.
“Historically speaking, that’s a very significant finding,” said Hanno Schaefer, a professor of plant biodiversity. “It’s becoming clearer that we’ve greatly neglected the North African region. We’ve focused too much on the Fertile Crescent and we need to invest more resources into studying the agriculture of North Africa.”
1. What can we learn about the Sudanese wild watermelon?| A．It is brightly colored and sugary. |
| B．It is consumed mainly by animals. |
| C．It has no connection with the domesticated type. |
| D．It has more differences than similarities to the domesticated type. |
| A．More resources will be devoted to agriculture research in South Africa. |
| B．The domesticated watermelon has a history of at least four thousand years. |
| C．The domesticated watermelon probably developed from the Sudanese type. |
| D．Few domesticated crops are from the Fertile Crescent of ancient Mesopotamia. |
| A．The history of the Sudanese wild watermelon. |
| B．Where wild watermelons actually come from. |
| C．The characteristics of domesticated watermelons. |
| D．How domesticated watermelons came into being. |
| A．Favorable. | B．Doubtful. | C．Critical. | D．Tolerant. |
Nature’s Lungs
We know that trees are nature’s purifier (净化器): They absorb carbon emissions (碳排放)and release oxygen. But their
According to the study, there are
This may sound like a lot,
Yet, planting trees is still considered the most effective way
3 . Suzanne Simard, a professor of forest ecology who called herself a “forest detective”, was raised in mountains in Canada. Few scientists make much impact with their PhD thesis, but, in 1997, she did just that. Her research on the “wood wide web” made the cover of Nature and transformed our understanding of forests. What was then a challenge to traditional ideas is today widely accepted.
A mushroom is the part of a fungus (真菌) that sticks up above the ground. Thin, white threads grow from its stem deep into the soil. These threads are called hyphae (菌丝). Hyphae connect themselves to tree roots. They also stretch from root system to root system, like an underground network. This network may go for miles. Hyphae pick up nutrients and water from soil. The fungus threads that connect to tree roots share their nutrients and water with the trees. In return, they sip a bit of the sugar the trees make. Sharing helps both trees and mushrooms live. It’s also how trees communicate.
When a tree is being eaten by bugs, it makes chemicals to shoo them away, sort of like bug repellent (驱虫剂). The chemicals travel through the tree, down its roots, and into the hyphae network. Other trees connected to the network taste the chemicals. That tells them a nearby tree is under attack, so they start to make their own bug repellent. Trees do more than share warnings through the hyphae. They also help each other. In the fall, paper birch trees drop their leaves and can no longer make sugar. So, a fir tree that stays green all winter uses the network to send extra sugar to the birch until spring comes again. This system of sharing information and nutrients through the hyphae is sometimes called the “wood wide web”, because it works a bit like the Internet.
Local climate sets the stage for the wood wide web, researchers say. In cool temperature and boreal forests, where wood and organic matter decay slowly, network-building EM fungi rule. By contrast, in the warmer tropics where wood and organic matter decay quickly, AM fungi dominate. These fungi form smaller webs and do less intertree swapping, meaning the tropical wood wide web is likely more localized.
Ecologist Thomas Crowther’s results suggest that as the planet warms, about 10% of EM-associated trees could be replaced by AM-associated trees. Microbes in forests dominated by AM fungi deal with carbon-containing organic matter faster, so they could liberate lots of heat-trapping carbon dioxide quickly, potentially accelerating a climate change process that is already happening at a frightening pace.
1. What do we know about Suzanne Simard?| A．She was a professor and a forest detective. |
| B．Growing up in the countryside, she made the cover of Nature. |
| C．Like many other scientists, she made big influence on her PhD thesis. |
| D．Her idea of the “wood wide web” used to challenge people’s thoughts. |
| A．They facilitate tree communication. | B．They form an underground network. |
| C．They produce sugar and share it with trees. | D．They share nutrients and water with the trees. |
| A．They release warning signals through leaves. |
| B．They produce real bug repellent to kill insects. |
| C．They make use of hyphae to produce chemicals. |
| D．They send chemical signals through the network. |
| A．It might slow down carbon release. | B．It would break down organic matter. |
| C．It might speed up climate change. | D．It might lead to faster tree growth. |
4 . The candy we eat, the tea we drink, the lotion we use---they all likely contain ingredients from wild plants. While natural ingredients can be beneficial to buyers, the way those plants are harvested could harm ecosystems. In a recent United Nations report, medicinal plant experts revealed the risks behind several of them, including Brazil nuts, frankincense, goldenseal, gum arabic, and licorice.
Plant derivatives （衍生物） in household products “sit there somewhere in the middle of the ingredients list” on product labels, often going unnoticed, says Caitlin Schindler, lead author of the report. Even if consumers do take note, there’s no information about what’s involved in obtaining or processing the derivatives.
Many of these plants are threatened with extinction from overharvesting, disease and pests, climate change, and habitat loss. The endangered state of more than 20,000 medicinal plant species has never been assessed, which means it’s impossible to know whether their use is sustainable.
Meanwhile, the trade in wild plants is booming. U. S. consumers spent more than $12.3 billion on herbal dietary supplements in 2021---up more than 9 percent from 2020. Wild plants have been used locally for centuries, but today’s global demand puts many at risk. And international customers often have no idea where these products originate.
Should consumers stop buying the products? No. Schindler says, because “the ingredients are really critical to a lot of people’s livelihoods.” Solutions for transforming the trade in wild plants are rooted in awareness. The first step for consumers is to “just notice that you’re buying something that has a wild ingredient,” she says. It’s generally safer to purchase local products and splurge on more expensive ones, if possible.
Consumers can also look for organic and fair-trade certifications. Various programs evaluate wild-plant supply chains for sustainability, and many companies advertise these certifications, either on the product or online. One of the most prominent is Fair Wild, which assesses environmental risks and recommends best sourcing practices. If certifications are missing, Schindler encourages people to challenge companies to do better. “Until businesses get a bit more pressure from consumers, we won’t see any changes happening,” she says.
1. What can we learn about wild plants according to the report?| A．Their current situation is ignored. | B．They are limited on a global scale. |
| C．They have been evaluated regularly. | D．Their process information is on the label. |
| A．Get rid of. | B．Spend much money on. |
| C．Pay attention to. | D．Conduct many experiments on. |
| A．They confirm the quality of the wild plants. |
| B．They offer consumers rights to assess the products. |
| C．They ensure the use of wild plants at a steady level. |
| D．They inspire companies to make more advertisements. |
A． | B． | C． | D． |
5 . In 1986, when he was only a prince. King Charles told a television interviewer that it was important to talk to plants. He was widely laughed at. But his wisdom seems to have been ahead of its time, for there is now plenty of evidence that plants can detect (察觉) sound, react to it, and even perhaps produce it.
Scientists have been experimenting with playing sounds to plants since at least the 1960s, during which time they have been exposed to everything from Beethoven to Michael Jackson. Over the years, evidence that this sort of thing can have an effect has been growing. One paper, published in 2018, announced that an Asian plant grew much larger leaves when exposed to 56 days of Buddhist chants — but not if it was exposed to Western pop music, or silence. Another, published last year, found that plants exposed to the noise of traffic from a busy motorway suffered slow growth, and produced a range of stress compounds (成分).
Another research reports that certain frequencies (频率), played in some environments like greenhouses, can affect seed growth and even improve crop production. And plants can make noises, too. Earlier this year a group of researchers at Tel Aviv University published an article in Cell Press, reporting that several plants gave out different noises in response to different stresses — although not at the sorts of frequencies that humans can hear. Humans can only hear frequencies of up to 16 kilohertz. Scientists discovered sounds given out by plants were up to 250 kilohertz.
If all that sounds strange, perhaps it should not. After all, sound carries useful information.
From an evolutionary point of view, there is no reason to expect that information to be applied only by animals.
1. What was most people’s attitude to Charles’ opinion?| A．Unclear. | B．Positive. | C．Cautious. | D．Negative. |
| A．Different sounds have different effects on plants. |
| B．Buddhist chants don’t make a difference to plants. |
| C．Western pop music does good to plants’ growth. |
| D．The noise of traffic produces stress compounds. |
| A．The sounds are strange. | B．The plants grow in greenhouses. |
| C．The plants are under great stress. | D．The sounds are at high frequencies. |
| A．It’s the important to talk to plants. |
| B．Sounds make a difference to plants. |
| C．Plants can discover and even make sound. |
| D．Humans can’t hear sounds produced by plants. |
6 . In times of intense stress, people sometimes let it out with a scream and a new study suggests that plants might do the same. Researchers at Tel Aviv University in Israel has found that plants let out ultrasonic (超声的) screams when damaged or stressed by drought.
The noises, falling within a range of 20 to 100 kilohertz, are too high-frequency for humans to hear, but other plants and some animals perceive them. Insects might be listening for sounds from stressed plants to assess their condition before laying eggs on their leaves. A moth (蛾) may decide against laying eggs on a plant that sounds water-stressed.
Researchers attached recording devices directly to plants to listen for secret sounds inside their stems (茎). In drought, air bubbles formed, burst and caused vibrations (振动) within the tissue that normally carries water up the plants’ stems. The process was picked up by the attached recording devices, but researchers wanted to know if any plant sounds could travel through the air.
So the team placed microphones 10 centimetres from stressed-out tomato and tobacco plants. They subjected one set of crops to drought and another to physical damage. A third group was untouched.
The microphones did pick up distinct sounds. On average, drought-stressed tomato plants let out about 35 ultrasonic screams per hour, while those with cut stems made about 25. Drought-stressed tobacco plants let out about 11 screams per hour, and cut crops made about 15 sounds in the same time. The average number of sounds from untouched plants fell below one per hour.
The researchers also attempted to identify each plant group just based on its screams. Using a type of artificial intelligence calculations, the team picked out distinct features in each set of sounds and successfully sorted their plants into three kinds: “dry, cut or untouched.”
If it is not too costly to set up the recording in a field situation, farmers might be able to hear these stress signals too. In future, enabling farmers to listen for water-stressed plants could “open a new direction”, which will be increasingly important as climate change exposes more areas to drought.
1. The moth is mentioned in paragraph 2 to show __________.| A．moths need enough water when laying eggs |
| B．some animals are able to hear plants scream |
| C．some insects are picky about their surroundings |
| D．wildlife species depend on each other when stressed |
| A．Plants’ sounds couldn’t be detected by humans. |
| B．Plants can be grouped according to their features. |
| C．Plants’ screams are related to stress types in a way. |
| D．Air bubbles contribute to the lack of water in plants. |
| A．Supporting evidence for the research result. |
| B．Potential application of the research findings. |
| C．A further explanation of the research methods. |
| D．A reasonable doubt about the research process. |
| A．Plants’ Vibrations: Way to React to Stress |
| B．Stress Signals: Secret Newly Found in Plants |
| C．Green Screams: Plants Make Noises When Stressed |
| D．Ultrasonic Screams: Discovery Opens a New Chapter |
Stretching along the west coast of North America from northern California to Alaska, the forests found along the Pacific Coast Range are the largest area of temperate (温带的) rainforest in the world. The forests are home to the coast redwood, the world’s tallest tree. Across the region, the forest understory (林下叶层) is wet and heavily vegetated.
Taiheiyo Evergreen Forests
Found in southern Japan, they are temperate rainforests of evergreen broadleaf trees. The forests can receive more than 100 inches of rain every year. The forests are covered by Japanese cedar and Japanese stone oak, while moso bamboo comprise the understory. The extent of the Taiheiyo forests has been reduced due to development and agriculture. Today,17%of the remaining forest is protected by national parks and other reserves.
Atlantic Oakwood Forest
The Atlantic Oakwood Forest covers the wettest parts of the United Kingdom. A species of oak tree (橡树) called sessile oak occupies the landscape. Unlike other temperate forests, these forests tend to have an open understory of grasses. Much of the historical range of the forest has given to agriculture and other development, though that has changed in recent decades.
Valdivian Temperate Rainforest
This forest is found on the west coast of Chile and Argentina, on the wet, western slopes (斜坡) of the Andes mountain range. With the coastline to the west, the peaks of the Andes to the east, and the Atacama Desert to the north, the region supports a number of plant and animal species found nowhere else in the world. Uniquely, the forest is covered by evergreen flowering trees, which are native to Chile and little known outside the region.
1. Which of the four forest areas occupies the most land?| A．Pacific Coast Range. | B．Taiheiyo Evergreen Forests. |
| C．Atlantic Oakwood Forest. | D．Valdivian Temperate Rainforest. |
| A．They have open understory grasses. | B．They’re home to extremely tall trees. |
| C．They’re of great historical significance. | D．They used to be affected by agriculture. |
| A．Wet climate. | B．Coastal location. |
| C．Evergreen flowering trees. | D．Well-protected national parks. |
8 . Emmanuel Mendoza, a college student, is currently running a study at Texas A&M University, where he’s mixing simulated (模拟的)Martian (火星的) soil and frass(粪便)from fly larvae(幼虫)to find just the right recipe for growing plants on Mars.
The seed of this idea was planted when Mendoza was in middle school, watching Ridley Scott’s 2015 film The Martian, in which Mark Watney becomes stuck on the planet and grows potatoes to survive. “That got me really interested in what nutrients or what soil structure Martian soil has that we could potentially take advantage of, ”Mendoza said.
Now, he’s running an experiment growing English peas in simulated Martian soil. “I definitely considered potatoes like Mark Watney, ”he said. “But the fact was that I couldn’t necessarily get the data I wanted out of them. ”
He wanted to be able to measure plant growth as it occurred throughout his experiment. Since potatoes grow underground, he’d only be able to collect data once they were done growing. In the end, Mendoza chose to grow English peas because they’re self-pollinating(自花传粉), grow fairly quickly and he can see the shoots climb.
Martian soil, though it does contain other essential nutrients, isn’t exactly ideal for plants from Earth. It tends to be rocky and lacks the right organic (有机 的)matter. Here’s where the larvae come in. Mendoza turned to the larvae of black soldier flies, which produce a waste known as frass. “They can break down almost any biomatter and turn it into really useful matter, “Mendoza said. “And then you can use the frass as a nutrient alternative to soil.”
For this experiment, Mendoza mixed different percentages of simulated Martian soil and frass to see what best supported growing English pea plants. Now, he said he’s seeing growth across all his plants—even the ones growing in 100%simulated Martian soil.
1. Why does the author mention the film The Martian?| A．To show Mendoza’s enthusiasm for films. |
| B．To illustrate Mark Watney’s intelligence. |
| C．To prove Mark Watney’s interest in gardening. |
| D．To introduce the origin of Mendoza’s experiment. |
| A．He was unwilling to repeat others’ study. |
| B．English peas grew far faster than potatoes . |
| C．Potatoes needed stricter living conditions. |
| D．It was more convenient to collect the data. |
| A．It serves as certain essential nutrients. |
| B．It loosens the soil for plants to grow. |
| C．It makes the soil become quite rocky. |
| D．It helps black soldier flies grow stronger. |
| A．Doubtful. | B．Pleased. | C．Intolerant. | D．Disappointed. |
9 . A new study reveals that trees can communicate and warn each other of danger. “For the first time, researchers have been able to visualize plant-to-plant communication,” said Masatsugu, senior author of the study.
The idea of talking trees started to take root in the 1980s. Two scientists found that damaged trees began producing chemicals that made their leaves unappetizing and indigestible to discourage insects. The trees then sent chemical signals to one another through the air. Over the past four decades, scientists have observed this cell-to-cell communication in more than 30 plant species.
Past research shows plants communicate with their surroundings by releasing chemicals known as volatile (易挥发的) organic compounds. One class of these compounds are released when a plant is injured: green leafy volatiles. These are released by, as the name suggests, pretty much every green plant with leaves, and are produced when a plant experiences physical damage. An example of these compounds is the smell released from fresh-cut grass.
In the new study, Masatsugu and his colleagues manually damaged leaves and placed insects on tomato plants to trigger the release of various green leafy volatiles. After testing many of them, the team found it seemed to increase calcium ions (钙离子) inside cells. The calcium signaling is like a switch to turn on the defense responses from the plants.
With this new understanding, researchers say plants could be immunized against threats and stressors before they even happen. For instance, exposing healthy plants to insect-ridden plants or the associated green leafy volatiles could boost their genetic defenses, so farmers use less pesticides. The revelation could also help make plants more resilient (有复原力的) during a drought, signaling the plants to conserve more water.
1. What does the new research find?| A．Trees can inform other trees of potential threats. | B．Trees can make themselves attractive. |
| C．Trees will send signals first once damaged. | D．Trees will work together to trick insects. |
| A．They defend insects. | B．They kill insects. |
| C．Some of them can be smelt. | D．Some of them can be seen. |
| A．By protecting trees from insects. | B．By classifying green leafy volatiles. |
| C．By increasing calcium ions inside cells. | D．By causing the release of certain chemicals. |
| A．Its target. | B．Its process. | C．Its application. | D．Its background. |
10 . Growing plants at home is a fun and enjoyable activity to do and can be developed as a new hobby.
Gardening reduces stress. Gardening is one of the most effective, and fun ways to free yourself from the physical, mental, and emotional stress you have been carrying since the beginning of the week. If you are overworking yourself during the weekdays or seeing yourself drowning in stressful thoughts, try to spend your weekends gardening at home.
Gardening is good for your heart. Gardening requires our body to move around by doing simple tasks such as digging the ground, planting seeds, pulling out weeds, and carrying a water container’s load.
By spending our free time gardening and monitoring our plants’ growth, we are also taking care of ourselves as we gain lots of health and emotional benefits. It is a worthwhile activity because we get to see the results of our hard work when our plants start growing fonder and healthier. The way we take care of our plants reflects the way we take care of ourselves.
| A．Gardening is an act of self-love. |
| B．Gardening is good for your bones. |
| C．Gardening helps your body against diseases. |
| D．You will see a significant change in your mind. |
| E．These simple gardening tasks can be considered a low-level exercise. |
| F．It also has several positive health and emotional benefits that you can enjoy. |
| G．Returning home to a place full of beautiful plants helps us enjoy the freshness of the air. |
