Flowers were more diverse a hundred million years ago than they are today, a new study has revealed. New research shows that flowering plants had already produced a large number of different flower types shortly after their emergence in the Cretaceous.
And in fact, in this ‘blooming’ period floral diversity was greater than that today. With at least 300,000 species, flowering plants are by far the largest group of plants living today. They first appeared at least 140 million years ago, when dinosaurs roamed the Earth.
To get their results the team analyzed 121 fossilized flowers and compared them to 1,201 living samples. Researchers have found that these historical flowers were much more varied than the living species we have today.
“Interestingly, it turned out that the Early Cretaceous flowers were on average more different from each other than today’s flowers, even though there are many more species of flowering plants on Earth today,” said Dr. Marion Chartier from the University of Vienna.
“Our results are fascinating because we only know a relatively small number of flowers from the Early Cretaceous, but this small number showed more variability than a thousand living species sampled for the study,” said Professor Andrea López.
They examined 30 floral characteristics in the samples to measure floral diversity and investigate patterns of floral evolution over time and across lineages. They found the historical plants to be much more different from each other, despite having fewer species. This evolutionary pattern is also seen in many animal groups such as dinosaurs and fish.
“For flowering plants, one possible explanation for this pattern is that when the group first evolved, floral organization was more flexible and novel flower types could evolve more easily,” said Dr. Maria von Balthazar.
“This flexibility may have allowed flowering plants, within a few million years of their origin, to adapt to the different animals that pollinated their flowers and dispersed their fruits,” she added.
“Our analyses clearly show that the morphological diversity of a given group does not necessarily correlate with species richness of that same group,” said Professor Jürg Schönenberger.
“In fact, some of the most species-rich groups of flowering plants, such as orchids and the daisy family, have managed to produce thousands of species while maintaining the same floral organization,” he added.
The team also discovered that certain combinations of features were theoretically possible, but apparently never produced by evolution and some particularly successful flower types arose independently several times.
“We are excited by these results. Our study opens up a new perspective and clearly shows that fossils are crucial to understanding the evolution of flowers,” concluded Dr. Susana Magallón.
Produced in association with SWNS Talker
