四级真题2024年12月第二套 Passage Two
① Chocolates save us from many things, especially emotional distress. They comfort us in times of trouble, calming down a racing heart by channelling happy calories inside us. We all have faith in chocolates to delight us in an instant!
② Recently, chocolate lovers were heartbroken as scientists claimed that they can become extinct by 2050! But hey, we have some happy news for you. Scientists can still help save chocolates from dying out! If you are not aware as to why scientists made the statement about the death of this wonderful thing, let us tell you the facts. Chocolate trees, whose seeds are used to make chocolate, grow in the tropical plant world and require very specific weather conditions to prosper.
③ Now, fifty percent of the world’s cocoa (可可) beans come from two countries in West Africa: Côte d’Ivoire and Ghana. Scientists believe that both of these countries will experience a 3.8°F temperature increase by 2050 due to global warming, endangering the cacao (可可树) farms in the rainforests. These farms will then have to be shifted to cooler mountainous areas, which are the natural habitat of wildlife. This will lead to some tough decisions: whether to grow chocolate or save wildlife.
④ Unfortunately, the crisis of global warming has already had a serious negative impact on cacao farms’ yields, leading to the prices of chocolates skyrocketing.
⑤ Scientists, however, are trying to find a long-term and eco-friendly solution to this problem! They are trying to modify the species with a gene-editing technology, which will transform the seedlings into a species that survives even in a drier and warmer climate.
⑥ According to a report by The Business Insider, in the University of California’s new bio- sciences building, tiny green cacao seedlings are lined up in refrigerated greenhouses for a new experiment by using a technology called CRISPR. By manipulating the DNA of plants, this technology is already being used across the world to make plants tougher and cheaper. Similarly, in this unconventional experiment, scientists will make tiny, precise changes to the DNA of the seedlings to make the cocoa crops survive in warmer and drier climates.
