Evolution in bloom

One of the great revolutions in the plant kingdom was the appearance of flowers. They didn’t actually arrive until late in the evolutionary process, about 130 million years ago, but when they did they radically transformed the face of the world. Let’s take a look at a successful seduction technique!

Over their billions of years on Earth, plants have evolved tremendously. From algae to trees, they have constantly “innovated” to survive in a changing environment. Revolutionary structures like stems, leaves, wood and seeds allowed them spread to every continent and refine their means of reproduction while achieving an amazing diversity. Flowers, however, were probably one of their greatest successes.

Before flowers, the Earth was covered mainly with gymnosperms (conifers and closely related modern plants), mosses and ferns. They relied mostly on wind and water to reproduce.

While gymnosperms were the first to use animals (insects) to help with reproduction, it was angiosperms (flowering plants) that really were able to make the most of this strategy. By combining male and female organs in a single structure, flowers are better adapted to pollination by insects and small animals. As these creatures move from one flower to another, they transfer the pollen and leave it in precisely the right spot for fertilization.

Then, once a flower has been fertilized, the ovary is transformed to produce a fruit, a protective envelope for the seeds or pit. And when animals eat the fruit, the seeds are spread even more efficiently.

This strategy has proved phenomenally successful. Angiosperms have become the most widespread group of plants on Earth. Today there are about 369,000 species of them, as compared with barely 1,100 species of conifers and their close relatives.

In fact, a huge number of insects and animals, as well as us humans, wouldn’t be able to survive without flowers!

They feed us, shelter us and brighten our days. Flowering plants are the dominant plant form now, but will they in turn be pushed aside one day by other forms and strategies better adapted to our changing environment? Only time (and our descendants) will tell.