VOA科学技术2014--Researchers Study Coffee's Beginnings

The coffee you had this morning could have its beginnings some 600,000 years ago.

Using genes¹ from coffee plants from around the world, researchers built a family tree for the world's most popular kind of coffee. Scientists call it Coffea arabica. Coffee lovers know it simply as "arabica."

The researchers recently published a new study about coffee. They found that the species appeared around 600,000 years ago. The plant was likely the result of natural breeding of two other coffee species.

Victor Albert of the University at Buffalo² was a co-leader of the study. He said the plant likely developed without the help of humans.

Wild coffee plants likely started in Ethiopia. But they are thought to have been first roasted and brewed⁴ in Yemen starting in the 1400s. In the 1600s, Indian monk⁵ Baba Budan is said to have taken seven raw coffee beans back to his homeland from Yemen, laying the beginnings for coffee's worldwide takeover.

Arabica coffee, loved for its smooth and sweet flavor, now makes up 60 to 70 percent of the global coffee market. The rest of the market is made up of robusta, a stronger and more bitter-tasting coffee made from one of arabica's parents, Coffea canephora.

To learn about arabica coffee's past, researchers studied the genetic⁶ information, or genomes, of C. canephora and another parent plant called Coffea eugenioides. They also studied more than 30 different arabica plants.

One of the plants was a sample from the 1700s provided by the Natural History Museum in London. The Swedish naturalist⁷ Carl Linnaeus used that plant to give coffee its scientific name.

The study appeared recently in the publication Nature Genetics. Researchers from Nestlé, a big Swiss food company which owns several coffee brands, helped with the study.

The arabica plant's population changed over thousands of years before humans began growing it. The arabica plants did well during warm, wet periods and suffered through dry ones. These difficult times created what scientists call "population bottlenecks," when only a small number of genetically⁸ similar plants survived.

Today, these genetic similarities mean arabica coffee plants are more likely to be hurt by diseases like coffee leaf rust⁹, which causes costly¹⁰ losses every year. The researchers explored the makeup¹¹ of one arabica variety that is resistant¹² to coffee leaf rust. They are interested in parts of its genetic code that could help protect the plant.

The study clarifies how arabica came to be and gives clues that could help protect the crop, said Fabian Echeverria of Texas A&M University. Echeverria was not involved with the research.

Exploring arabica's past and present could help give information about how to keep coffee plants healthy - ensuring morning cups of coffee into the future.

Words in This Story

family tree -n. a drawing that shows ancestors and offspring of a living thing

species - n. a group of plants that are similar and can produce young animals or plants

breeding -n. producing offspring

roast - v. to cook with dry heat in an oven or over a fire

brew³ - v. to make coffee

sample - n. a small amount of something that gives you information about the thing it was taken from

genetic code -n. the series of genetic substances that can be identified by scientists and linked to genetic qualities in species and individuals

1 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

2 buffalo   

n.(北美)野牛；(亚洲)水牛

参考例句：

• Asian buffalo isn't as wild as that of America's. 亚洲水牛比美洲水牛温顺些。
• The boots are made of buffalo hide. 这双靴子是由水牛皮制成的。

3 brew   

v.酿造，调制

参考例句：

• Let's brew up some more tea.咱们沏些茶吧。
• The policeman dispelled the crowd lest they should brew trouble.警察驱散人群，因恐他们酿祸。

4 brewed   

调制( brew的过去式和过去分词 )； 酝酿； 沏（茶）； 煮（咖啡）

参考例句：

• The beer is brewed in the Czech Republic. 这种啤酒是在捷克共和国酿造的。
• The boy brewed a cup of coffee for his mother. 这男孩给他妈妈冲了一杯咖啡。 来自《简明英汉词典》

5 monk   

n.和尚，僧侣，修道士

参考例句：

• The man was a monk from Emei Mountain.那人是峨眉山下来的和尚。
• Buddhist monk sat with folded palms.和尚合掌打坐。

6 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

7 naturalist   

n.博物学家(尤指直接观察动植物者)

参考例句：

• He was a printer by trade and naturalist by avocation.他从事印刷业，同时是个博物学爱好者。
• The naturalist told us many stories about birds.博物学家给我们讲述了许多有关鸟儿的故事。

8 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

9 rust   

n.锈；v.生锈；(脑子)衰退

参考例句：

• She scraped the rust off the kitchen knife.她擦掉了菜刀上的锈。
• The rain will rust the iron roof.雨水会使铁皮屋顶生锈。

10 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

11 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

12 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。