Plant life on Earth is much older than we thought
Plants appeared on Earth 100 million years earlier than scientists previously thought.
The evolution of plant life on Earth is fundamental to the history of our planet. It has provided resources and habitats for animals and influenced climate on a global scale.
We know that plant life on land is ancient, but exactly how old is widely debated.
Now, Museum scientists are part of a multi-institutional team transforming our understanding of this most formative episode in Earth's history.
Their latest findings, published in the journals Proceedings of the National Academy of Sciences and Current Biology, show that land plants evolved about 100 million years earlier than previously thought.
New data and analysis show that plant life began colonising land 500 million years ago, during the Cambrian Period, around the same time as the emergence of the first land animals.
These studies are also improving our understanding of how the plant family first evolved.
Lowly liverworts have been generally considered the most primitive of existing plants. Liverworts are flowerless, spore-producing plants that lack features characteristic of other land plants, such as roots, or pores on their surfaces for gas and water exchange.
It has generally been assumed that the earliest land plants were liverwort-like and therefore much research effort has been poured into studying this group and developing it as a model for the ancestral land plant.
The research published in Current Biology shows this assumption is incorrect. In the family tree of plants, liverworts and mosses are in fact sisters, and both are distant cousins to the ancestors of ferns and flowers.
This change in our understanding of relationships implies that liverworts lack key features present in all other living land plants because they have lost them. The first land plants were therefore probably more complex than previously understood.
Silvia Pressel, a researcher in botanical diversity at the Museum, says, 'Taken together, these findings are important for developing our knowledge of how model organisms can help us understand the evolution of the fundamental features that make plants, like stems, roots and leaves. '