New Research Learns Evolution of Flowering Plants
2024-05-02
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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.