Understanding of Earth's flowering plants blossoms in genome study

New research based on genome data for 9,506 species, as well as an examination of 200 fossils, provides the deepest understanding to date of the evolutionary history of flowering plants, called angiosperms

Flowering plants - from corn, wheat, rice and potatoes to maple, oak, apple and cherry trees as well as roses, tulips, daisies and dandelions and even the corpse flower and voodoo lily - are cornerstones of Earth's ecosystems and essential for humankind.

New research based on genome data for 9,506 species, as well as an examination of 200 fossils, provides the deepest understanding to date of the evolutionary history of flowering plants, called angiosperms - the largest and most diverse plant group. It details how angiosperms appeared and became dominant during the age of dinosaurs and how they have changed over time.

The scientists devised a new tree of life for angiosperms, covering 15 times more types of flowering plants - nearly 60% of them - than the nearest comparable study.

"It is a massive leap forward in our understanding of plant evolution," said botanist William Baker of the Royal Botanic Gardens, Kew (RBG Kew) in London, senior author of the research published on Wednesday in the journal Nature.

Angiosperms, plants that produce flowers and generate their seeds in fruits, encompass about 330,000 species and comprise about 80% of the world's plants. They include, among others, all the major food crops, grasses, most broad-leaved trees and most aquatic plants. Their closest relatives are the gymnosperms, a group that preceded them on Earth and includes conifers and some others, with a bit more than 1,000 species.

The study identified two pulses of diversification among angiosperms. The first one occurred around 150-140 million years ago at the dawn of their existence during the Mesozoic era, with 80% of major angiosperm lineages arising during that time. The next one happened about 100 million years later during the Cenozoic era, after the demise of the dinosaurs and the rise of mammals, amid decreasing global temperatures.

"Angiosperms have many structural adaptations that confer advantages over gymnosperms, but chief among these are those contributing to reproductive success," Baker said.