Study Reveals History, Travels of Baobab Tree
2024-05-26
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1The baobab tree is a special thing to see.
2During the dry season, its leafless branches look like roots coming from a thick trunk.
3It appears as if someone took a tree from the ground, flipped it on its head and put it back into the earth.
4That is why the tree is sometimes called the "upside down tree."
5Baobab trees grow in Madagascar, mainland Africa and Australia.
6The origins and history of the baobab have been something of a mystery.
7But a new study that looked at all eight recognized species helps tell the baobab's story.
8The baobab originated in Madagascar about 21 million years ago.
9It reached the African continent and Australia sometime in the past 12 million years, researchers found.
10Madagascar, an island off Africa's southeastern coast, has a large ecosystem.
11It is home to many kinds of plants.
12Two baobab lineages went extinct in Madagascar.
13But the lineages established themselves elsewhere, one in mainland Africa and one in Australia, the study showed.
14It appears that baobab seed pods floated from Madagascar to mainland Africa, located about 400 kilometers to the west.
15The seeds also traveled to Australia, nearly 7,000 kilometers to the east.
16"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.
17He is one of the writers of the study, which appeared recently in the publication Nature.
18Wan added that the seeds were able to travel to Australia because of the Indian Ocean gyre, an oceanic current.
19Baobab trees provide food, shelter and nesting places for wildlife, including bees, birds and various mammals.
20Their fruits also provide important nutrients and medicines for people.
21Baobab leaves can be eaten, too.
22The trees produce large, sweet-smelling flowers.
23Their sugary nectar appeals to nighttime pollinators like fruit bats and hawk moths.
24Their flowers also attract two kinds of primates -- lemurs in Madagascar and bush babies in Africa.
25Ilia Leitch is a plant geneticist at the Royal Botanic Gardens Kew in London.
26He is also a study co-writer. He said baobabs can grow to be very large and live for thousands of years.
27Their very large root systems "play an important ecological role, helping to slow down soil erosion and enabling nutrient recycling," he said.
28Baobabs are a water source for local people during the dry season.
29But Africa's baobabs are at risk from elephant damage.
30The animals sometimes cut the tree trunks with their tusks to get water.
31I'm Dan Novak.
1The 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. 2That is why the tree is sometimes called the "upside down tree." 3Baobab 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. 4The 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. 5Two baobab lineages went extinct in Madagascar. But the lineages established themselves elsewhere, one in mainland Africa and one in Australia, the study showed. 6It 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. 7"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. 8Wan added that the seeds were able to travel to Australia because of the Indian Ocean gyre, an oceanic current. 9Baobab 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. 10The 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. 11Ilia 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. 12Their very large root systems "play an important ecological role, helping to slow down soil erosion and enabling nutrient recycling," he said. 13Baobabs 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. 14I'm Dan Novak. 15Dan Novak adapted this story for VOA Learning English based on reporting by Reuters. 16_________________________________________________ 17Words in This Story 18trunk - n. the thick main stem of a tree 19origin - n. the point or place where something begins or is created 20lineage - n. the people who were in someone's family in past times 21pod - n. a long, thin part of some plants that has seeds inside 22raft - n. a flat structure that is used for floating or sailing on water 23pollinator - n. to give pollen from another plant of the same kind so that seeds will be produced 24erosion - n. the gradual destruction of something by natural forces 25enable - v. to make able to do or to be something 26tusk - n. a very long, large tooth that sticks out of the mouth of an animal