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Flowering plants and insects share a pollen-and-nectar history that goes back a long way. According to fossil records most of the insect groups originated before flowering plants appeared, which is some 140 to 190 million years ago. This would be during the late Jurassic and early Cretaceous periods.
Scientists at the National Evolutionary Synthesis Center of Duke University and Environmental Science Center of Yale University, usa, shift the origin of flowering plants back further to 215 million years ago in the Triassic period.
This is a good 25 to 75 million years earlier than what is known.
The find means flowering plants and insects arrived together almost.
The groups used genetic comparisons of living plants and clues from fossils to reconstruct the relationships among more than 150 terrestrial plant species. While the dates for lower plants like mosses, ferns and pines matched with the fossil evidence, the origin of flowering plants was not in conformity. “We see the same kind of discrepancy in animal groups, too, like mammals and birds,” said Michael Donoghue from the Yale University who led the study. The results were published online in the Proceedings of the National Academy of Sciences on March 16.
Commenting on the disconnect between the new studies and the earlier fossil estimates, S R Yadav at the department of botany in Delhi University said: “With the molecular discoveries, the whole concept of primitive flowering plants and their origin is a mystery.”