It is a mystery of nature that is perhaps being lifted. A recent CNRS study tells us more about the arrival of plants on Earth.

How did plants come to earth 450 million years ago? It was actually algae - plant life was everywhere in the water before arriving on Earth - that managed to conquer the mainland, and allowed the development of life as we know it today. This is the subject of a recent CNRS study on the origin of plants.

It was 450 million years ago. Algae living probably in a pond have ventured on land and have developed the very first plants. They were probably already green, with some filaments that linked them to the ground.

Modification, adaptation, reinforcement

Over time, they change to adapt to their new environment, strengthen themselves to protect themselves from the sun, absorb nitrogen, essential to their growth.

But above all, to survive on Earth, explains Pierre-Marc Delaux, researcher at the CNRS, the plants fed on bacteria around them, and came into contact with the micro-organisms that surrounded them: "They were probably also associated with mushrooms to better capture the nutrients of this hostile soil ".

By associating themselves with the micro-organisms that surrounded them, the plants developed over millions of years. This is a food for thought, say the researchers. This shows that there are many possibilities to stimulate plant growth in a natural way, without fertilizer or chemical.