When did Earth's first forests emerge?

California's redwoods are the tallest living plants on Earth, while the Amazon is the largest tropical rainforest. They have a birth date. Plants first appeared on land about 470 million years ago, but trees and forests didn't appear until nearly 400 million years ago.

Chris Berry, a paleobotanist atCardiff University in the United Kingdom, told Live Science that plant life slowly evolved genetic precursors needed to produce trees.

The oldest forest on record was reported in the journal Current Biology.

Is there a scientific way to determine if trees exist?

The root systems of ancient trees were found at the Cairo site. We can see a map of where the trees were, but we don't see the fossils. The ecology of the forest is what we learned.

According to a report from a New York university, the ancient plant Archaeopteris boasted large roots and branches similar to modern trees. The arrival of the plants was 20 million years later than previously thought.

Berry said that the development of the early forests depended on the evolution of the trees. He believes that the triggering is the development of anatomies which allow more complex branching. Plants had evolved the genetic toolkit to be able to build tree-like structures. The first roots arrived in the early Devonian, while the early branching systems were developed just before the Silurian period. The ability to rise above competition is a tree trait.

At least one important tree feature might have been made possible by some environmental changes. Megaphylls, leaves that are common today and are characterized by branching veins, can grow large enough to absorb more sunlight. According to a 2001 study in the journal Nature, they first appeared about 400 million years ago but became widespread only 30 million years later.

The study found that Earth was too hot for megaphyll leaves because of high CO2 levels. They would absorb too much sun and get overheated. Megaphylls were able to take in more CO2 due to the reduction in greenhouse gas levels. The forest revolution could be pushed forward by leaves like this.

It was originally published on Live Science