New Research Learns Evolution of Flowering Plants
2024-05-02
LRC
TXT
大字
小字
滚动
全页
1Flowering plants are very important to Earth's ecosystems. They are necessary for life on Earth.
2Flowering plants are also called angiosperms.
3They are the largest and most diverse plant group.
4Flowering plants include corn, wheat, rice and potatoes to maple, oak, apple and cherry trees.
5New research based on genome data for 9,506 species of flowering plants provides the deepest understanding yet of their evolutionary history.
6The research explains how angiosperms appeared and became widespread during the age of dinosaurs.
7It also offers explanations for how such plants have changed over time.
8The team of scientists created a new tree of life for angiosperms.
9A tree of life is a tool that biologists use to see the evolutionary relationships among plants, animals and other life forms.
10Their new tree of life covers 15 times more kinds of flowering plants than the closest comparable study.
11"It is a massive leap forward in our understanding of plant evolution," said William Baker.
12He is a plant expert with the Royal Botanic Gardens, Kew, in London.
13He is senior writer of the research study, which appeared last week in the publication Nature.
14Angiosperms are plants that produce flowers and produce their seeds in fruits.
15They are made up of about 330,000 species. About 80 percent of the world's plants are angiosperms.
16They include, among others, all the major food crops, grasses, most large-leaved trees and most aquatic plants.
17Their closest relatives are the gymnosperms, a group that came before them on Earth.
18The study identified two periods of diversification among angiosperms.
19The first one occurred around 150 million to 140 million years ago during the Mesozoic era.
20At that time, 80 percent of major angiosperm species arose.
21The next one happened about 100 million years later during the Cenozoic era, after the extinction of the dinosaurs and the rise of mammals.
22That period saw decreasing world temperatures.
23Baker said angiosperms are more successful at reproducing than gymnosperms.
24Gymnosperms and angiosperms both have seeds. But the flowering plants have enclosed seeds that protect them from dehydration.
25This permits them to survive in a wider range of environments, from deserts to Antarctica.
26They also evolved the flower, a structure that permitted them to form relationships with animal pollinators, especially insects.
27Gymnosperms usually depend upon the wind for pollination.
28Angiosperms evolved a high diversity of fruit types, permitting effective seed spread.
29Flowering plants provide most of the calories that humans eat, from grains to fruits to vegetables.
30"They are sources of many of our medicines and hold potential solutions to global challenges, such as climate change, biodiversity loss, human health, food security and renewable energy," Baker said.
31The study could help scientists better understand disease and pest resistance in angiosperms.
32And the research could help find new medicines.
33Alexandre Zuntini is Royal Botanical Gardens botanist and a lead writer of the study.
34He said that some plant "lineages may hold chemical compounds or even genes that can be useful for survival of our species."
35I'm Dan Novak.
1Flowering plants are very important to Earth's ecosystems. They are necessary for life on Earth. 2Flowering plants are also called angiosperms. They are the largest and most diverse plant group. Flowering plants include corn, wheat, rice and potatoes to maple, oak, apple and cherry trees. 3New research based on genome data for 9,506 species of flowering plants provides the deepest understanding yet of their evolutionary history. The research explains how angiosperms appeared and became widespread during the age of dinosaurs. It also offers explanations for how such plants have changed over time. 4The team of scientists created a new tree of life for angiosperms. A tree of life is a tool that biologists use to see the evolutionary relationships among plants, animals and other life forms. Their new tree of life covers 15 times more kinds of flowering plants than the closest comparable study. 5"It is a massive leap forward in our understanding of plant evolution," said William Baker. He is a plant expert with the Royal Botanic Gardens, Kew, in London. He is senior writer of the research study, which appeared last week in the publication Nature. 6Angiosperms are plants that produce flowers and produce their seeds in fruits. They are made up of about 330,000 species. About 80 percent of the world's plants are angiosperms. They include, among others, all the major food crops, grasses, most large-leaved trees and most aquatic plants. 7Their closest relatives are the gymnosperms, a group that came before them on Earth. 8The study identified two periods of diversification among angiosperms. The first one occurred around 150 million to 140 million years ago during the Mesozoic era. At that time, 80 percent of major angiosperm species arose. The next one happened about 100 million years later during the Cenozoic era, after the extinction of the dinosaurs and the rise of mammals. That period saw decreasing world temperatures. 9Baker said angiosperms are more successful at reproducing than gymnosperms. 10Gymnosperms and angiosperms both have seeds. But the flowering plants have enclosed seeds that protect them from dehydration. This permits them to survive in a wider range of environments, from deserts to Antarctica. 11They also evolved the flower, a structure that permitted them to form relationships with animal pollinators, especially insects. Gymnosperms usually depend upon the wind for pollination. Angiosperms evolved a high diversity of fruit types, permitting effective seed spread. 12Flowering plants provide most of the calories that humans eat, from grains to fruits to vegetables. 13"They are sources of many of our medicines and hold potential solutions to global challenges, such as climate change, biodiversity loss, human health, food security and renewable energy," Baker said. 14The study could help scientists better understand disease and pest resistance in angiosperms. And the research could help find new medicines. 15Alexandre Zuntini is Royal Botanical Gardens botanist and a lead writer of the study. He said that some plant "lineages may hold chemical compounds or even genes that can be useful for survival of our species." 16I'm Dan Novak. 17Dan Novak adapted this story for VOA Learning English based on reporting by Reuters. 18_____________________________________________ 19Words in This Story 20ecosystem - n. everything that exists in a particular environment 21diverse - adj. different from each other 22evolution - n. a theory that the differences between modern plants and animals are because of changes that happened by a natural process over a very long time 23leap - n. to suddenly increase by a large amount 24aquatic - adj. living or found in or near water 25enclose - v. to surround 26dehydrate - v. to remove water or moisture from 27source - n. someone or something that provides what is wanted or needed 28challenge - n. to say or show that may not be true, correct, or legal 29botanist - n. a branch of science that deals with plant life 30lineage - n. the people who were in someone's family in past times