第2211期:Study Reveals History, Travels of Baobab Tree

The baobab tree is a special thing to see. During the dry season, its leafless branches look like roots coming from a thick trunk. It appears as if someone took a tree from the ground, flipped it on its head and put it back into the earth. 

猴面包树是一处特别值得一看的东西。 在旱季，它光秃秃的树枝看起来就像从粗大的树干上长出来的根。 看起来就像有人从地上取下一棵树，将其翻转，然后将其放回土中。 

That is why the tree is sometimes called the "upside down tree." 

这就是为什么这棵树有时被称为“颠倒树”。 

Baobab trees grow in Madagascar, mainland Africa and Australia. The origins and history of the baobab have been something of a mystery. But a new study that looked at all eight recognized species helps tell the baobab's story. 

猴面包树生长在马达加斯加、非洲大陆和澳大利亚。 猴面包树的起源和历史一直是个谜。 但一项针对所有八种已识别物种的新研究有助于讲述猴面包树的故事。 

The baobab originated in Madagascar about 21 million years ago. It reached the African continent and Australia sometime in the past 12 million years, researchers found. Madagascar, an island off Africa's southeastern coast, has a large ecosystem. It is home to many kinds of plants. 

猴面包树起源于大约 2100 万年前的马达加斯加。 研究人员发现，它在过去 1200 万年的某个时候到达了非洲大陆和澳大利亚。 马达加斯加是非洲东南沿海的一个岛屿，拥有庞大的生态系统。 它是多种植物的家园。 

Two baobab lineages went extinct in Madagascar. But the lineages established themselves elsewhere, one in mainland Africa and one in Australia, the study showed. 

马达加斯加的两个猴面包树谱系灭绝了。 但研究显示，这些谱系在其他地方建立起来，一个在非洲大陆，一个在澳大利亚。 

It appears that baobab seed pods floated from Madagascar to mainland Africa, located about 400 kilometers to the west. The seeds also traveled to Australia, nearly 7,000 kilometers to the east. 

看来，猴面包树的种子荚是从马达加斯加飘到了以西约 400 公里处的非洲大陆。 这些种子还到达了以东近7000公里的澳大利亚。

"The plants almost certainly got to Africa and Australia floating on or with vegetation rafts," said plant expert Tao Wan of the Wuhan Botanical Garden in China. He is one of the writers of the study, which appeared recently in the publication Nature. 

中国武汉植物园的植物专家陶万说：“这些植物几乎肯定是漂浮在植被筏上或随植筏一起到达非洲和澳大利亚的。” 他是该研究的作者之一，该研究最近发表在《自然》杂志上。

Wan added that the seeds were able to travel to Australia because of the Indian Ocean gyre, an oceanic current. 

万补充说，由于印度洋环流（一种洋流），这些种子能够传播到澳大利亚。 

Baobab trees provide food, shelter and nesting places for wildlife, including bees, birds and various mammals. Their fruits also provide important nutrients and medicines for people. Baobab leaves can be eaten, too. 

猴面包树为蜜蜂、鸟类和各种哺乳动物等野生动物提供食物、庇护所和筑巢地。 它们的果实还为人们提供重要的营养物质和药物。 猴面包树的叶子也可以吃。

The trees produce large, sweet-smelling flowers. Their sugary nectar appeals to nighttime pollinators like fruit bats and hawk moths. Their flowers also attract two kinds of primates -- lemurs in Madagascar and bush babies in Africa. 

这些树会开出大而芳香的花朵。 它们含糖的花蜜吸引了果蝠和天蛾等夜间传粉者。 它们的花还吸引了两种灵长类动物——马达加斯加的狐猴和非洲的丛林宝宝。 

Ilia Leitch is a plant geneticist at the Royal Botanic Gardens Kew in London. He is also a study co-writer. He said baobabs can grow to be very large and live for thousands of years. 

伊利亚·雷奇 (Ilia Leitch) 是伦敦皇家植物园邱园的植物遗传学家。 他也是一名研究合著者。 他说猴面包树可以长得很大并且可以存活数千年。 

Their very large root systems “play an important ecological role, helping to slow down soil erosion and enabling nutrient recycling,” he said. 

他说，它们非常大的根系“发挥着重要的生态作用，有助于减缓土壤侵蚀并实现养分循环利用”。 

Baobabs are a water source for local people during the dry season. But Africa's baobabs are at risk from elephant damage. The animals sometimes cut the tree trunks with their tusks to get water. 

猴面包树是当地人旱季的水源。 但非洲的猴面包树面临着大象破坏的风险。 这些动物有时会用獠牙砍断树干来取水。