Newfound fossils show that flowering plants may have existed with dinosaurs.

The research suggests that that flowering plants arose 100 million years earlier than scientists previously thought.

Flowering plants are now the dominant form of plant life, but they were the last group to appear in history.

Flowering plants evolved from relatives of seed-producing plants that do not flower, such as conifers and cycads. Angiosperms, or flowering plants, or angiosperms, became the dominant plants about 90 million years ago--but when they originated has been debated by scientists.

"Flowering plants were the last group of plants appearing in Earth's history," said Peter Hochuli, a who is co-author of the study and a paleobotanist at the University of Zrich's Paleontological Institute and Museum.

He added,"They are an extremely successful group on which all terrestrial ecosystems today depend, including the existence of humanity."

Scientists used microscopes on fossils to examine ancient grains of pollen. The fossils, which were discovered in core samples of ice drilled from northern Switzerland.

"Our findings suggest that the origin of flowering plants is rooted much deeper than originally thought," Hochuli said.

Researchers analyzed the structure of the grains and found that the plants were pollinated by insects. The insects were probably beetles-- bees didn't evolve for another 100 million years.

Researchers found a total of six different types of pollen. This suggests that flowering plants were more diverse than previously thought.

Researchers have found similar pollen grains in Switzerland and Scandanavia; both regions were tropical during the Middle Triassic Period.  The region area that now composes Switzerland was far more dry than the Barents Sea region. This suggests that the plants flourished in a range of environments.

The fossil record of flowering plants dates back 140 million years, but scientists haven't been sure why or how they dominated the planet so quickly. ."This sudden appearance has bothered scientists ever since Darwin,who called the origin of flowering plants an 'abominable mystery,'" Hochuli said.

The new evidence shows that because plants existed so much earlier than previously thought, they may have had more time to spread and diversify before they "took over" on land.

Still a mystery, though, is how they originated.

"So far, no direct ancestors of flowering plants are known," Hochuli said. "Some groups of plants are suspected to be closely related. But the evidence is weak, and most of these groups are thought to be too specialized to be at the base of the flowering plants."