Nowadays, more and more people decide to have children later in life. What do you think are the reasons for this? Do the advantages of this trend outweigh the disadvantages? Give reasons for your answer and include any relevant examples from your own knowledge or experience. Write at least ...
How did Earth get so many species(物种)? For thousands of years, people wond-ered. In the 1840s, one naturalist (博物学家) had an idea. His name was Charles Darwin. He spent his whole life studying animals and insects. Darwin thought that new species developed slowly, as populations of...
对食品安全问题不放心4个月，伴反复检查、苦恼2个月。具体表现为：不敢在外边的饭店吃饭，担心饭店的菜洗不干净，炒菜用的油是泔水。不敢吃牛肉干，害怕得疯牛病，不敢吃猪肉，猪饲料中激素太多。尤其是“福寿螺”事件后，不仅小龙虾之类，甚至海鲜类的食物也拒绝吃了。米饭也是尽能少吃，因为大米上的农药...
However, more recent research indicates that there are more likely only six with an additional ten subspecies. How can this be?Let's first take a look at the history of naming the species. Dr. B. L. Burtt studied the genus Saintpaulia in the 1940's-1960's and published a taxonomy ...
All over the world,wild places are in trouble. As the humanpopulation has increased, we’ve taken over more and more land for ourhomes, farms, factoriesandroads. In therainforest, around80,000 acres of treesare cut down every day to make way forfarming, or to providewoodfor industry. ...
It's that time of year again when the RSPB ask the people of the UK to take part in their annual Big Garden Birdwatch. Here's what to know for 2025...
However, electric vehicles require a host of innovations in other spheres, such as high-capacity rechargeable batteries and charging infrastructure. In addition, the benefits of electric vehicles are limited by the fact that many power grids still rely on fossil fuels. ...
If, however, the tree descended from a ‘Saigon’ mango, it has a different heritage. ‘Saigon,’ as the name suggests, is native to Vietnam. It came to Miami in 1902. The place most commonly recognized as thehome of this tree is Miami, Florida. Whether the parent was ‘Haden’ or...
But that image has come under inspection in recent years, as shark researchers around the world have discovered the fish gathering in large numbers and interacting with others of their own species in ways that are obviously friendly. Yannis Papastamatiou, a marine scientist at Florida ...
But many of those species, known and unknown, are destroyed every day. Moreover, constant logging, mining and raising domestic animals cause a gradual disappearance of the Amazon jungles.How many new species of monkeys have been identified in Brazil alone over the last year A.Eight.B.Nine.C...