閱讀優秀的英語文摘

我們學習英語的過程中是一定不可以偷懶的，學習英語是要持之以恆的，只要我們多多看一些英語，所以小編今天給大家整理了英語的文摘，大家快點學習起來，纔會更快的提升英語成績哦，有需要的同學可以收藏起來哦，

　　雜草爲何容易重生

Why Crabgrass Always Wins at Monopoly

雜草爲何容易重生

Crabgrass is an ugly, obnoxious weed that is the scourge of the perfect lawn and its perfectionist gardener. Along with being an eyesore, it’s also responsible for a substantial amount of crop loss on commercial farms.

雜草醜陋而令人生厭。是整齊的草坪和崇尚完美主義園丁的禍害。除了難看之外，它還要爲商業農場農作物收成大量受損承擔責任。

Weeding Out Competition

淘汰競爭

Common wisdom says that crabgrass is hard to get rid of because it crowds out the plants around it, and does not allow them to get enough space and nutrients. However, scientists have long wondered if crabgrass dominates your lawn’s real estate by using a technique called allelopathy. This literally means “others suffering,” and occurs when a plant harms another by emitting toxic substances into the environment, usually through the soil.

按照常理，這種雜草很難根除是因爲它排擠周圍的植物使得它們沒有充足的生長空間和養料。然而，科學家們一直想知道，這種雜草是否通過使用一種名爲植化相剋的方法支配你家草坪的居住權。這個術語字面上的意思是"非我族類，連根清除"。當某種植物通過釋放有毒物質到環境中(通常通過土壤)來傷害其他植物時，這種現象就在發生。

Researchers from Nankai University, China Agricultural University, and the Chinese Academy of Sciences all found that crabgrass uses this method of “weeding out” neighboring plants.

來自南開大學，中國農業大學，和中國科學院的研究人員都發現這種雜草使用這個方法清除周圍的植物。

In their experiment, researchers isolated three chemicals from crabgrass roots and nearby soil, and then added them to potted plants of wheat, maize, and soybeans. Sure enough, the plants treated with crabgrass toxins did not grow as well.

在實驗中，研究人員從這種雜草的根部和其周圍土壤中隔絕出三種化學物質，然後將它們加入盆栽的小麥，玉米和大豆中。不出所料，受這種雜草毒素影響的植物都生長不佳。

Chemical Warfare

化學戰爭

Tests revealed that the compounds reduced the amount of carbon in the soil’s microbial biomass. This means crabgrass can actually change the makeup of the bacteria in the dirt around it. Since plants rely on bacteria in order to absorb key nutrients such as nitrogen and organic compounds, the vicious weed makes life extremely hard on its surrounding neighbors.

這些試驗揭示了該複合物降低了碳在土壤中微生物生物量中碳的數量。這意味着這種雜草確實能夠改變其周圍泥土中細菌的組成。因爲植物依靠細菌來吸收諸如氮和有機化合物這樣的重要養分，邪惡的雜草使它的鄰居的生存極爲艱難。

So the next time you squirt Round‑Up on that pesky patch of crabgrass, remember that the weed is emitting a little herbicide of its own. It’s chemical warfare, right under your nose.

所以下次，當你向那一撮討厭的雜草噴除草劑時，要記住雜草自身會釋放一些除草劑。在你的眼皮子底下進行一場化學戰爭。

　　烹飪與人類的智慧

Cooking Up Human Intelligence

烹飪與人類的智慧

So what makes the human brain so special? Actually, it might not be that special after all.

所以說是什麼讓人類的大腦如此特別?實際上，這或許根本就不特別。

Sliding Scales

變化的幅度

In 2009, Dr. Suzana Herculano Houzel and her colleagues showed that the human brain has the same density of nerve cells as other primates. Comparing humans to smaller primates, she claims that our brain is no bigger than it should be for our body size. Still, given the distinctive way that primate brains scale with size, we may have the most brain cells of any mammal.

在2009年，蘇珊娜·埃爾庫拉諾·烏澤爾博士和她的同事們展示了人類大腦的神經細胞密度和其它的靈長類動物一樣。與其它較小的靈長類動物相比，蘇珊娜博士稱我們的大腦與我們自身體型相比並不算大。但考慮到靈長類動物大腦尺寸比例的獨特方式，人類擁有所有哺乳動物中最多的腦細胞。

That being said, gorillas can grow to be three times our size, but still have much smaller brains than ours.

話雖如此，大猩猩能長到我們體型的三倍，但它們的大腦仍然比我們小得多。

Brain cells need more energy than most body cells. Although the brain is less than 2 percent of the mass of the human body, it consumes 20 percent of our resting metabolic energy. Gorillas have to spend more than eight hours every day eating to get enough calories to support their big body, and they simply can’t afford a bigger brain.

腦細胞比其它身體細胞需要更多的能量。雖然大腦所佔人體的比重小於2%，但它卻消耗我們靜止時代謝能的20%。爲了給龐大的身軀提供足夠的能量，大猩猩每天要花費超過8小時的時間進食，因此它們無法負擔更大的大腦。

Brain Food

大腦的食物

So, then, how did human ancestors overcome this limitation? Beginning with homo erectus, about two million years ago, our ancestors couldn’t have afforded the metabolic cost of their increasingly large brains if they ate raw food like gorillas do.

所以，人類的祖先又是如何突破限制的?從直立的人類開始，大約兩百萬年前，隨着大腦越來越大，如果人類的祖先還像大猩猩那樣進食生的食物，那麼他們將無法給大腦提供足夠的代謝值。

Primatologist Richard Wrangham thinks that the invention of cooking with fire is what made this growth in brain size possible. Cooked food is easier to digest and yields more calories. Cooking may have made the human brain possible, and freed us from having to spend all day eating.

靈長類動物學家理查德·蘭厄姆認爲發明用火烹飪，使得大腦生長變大成爲可能。烹煮的食物更容易消化並且能產生更多的熱量。烹飪或許促進了人腦的形成，並將人類從整日進食的境況中解放出來。