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World - Tectonic Tales of Life: How Geology Has Influenced Evolution for the Past 500 Million Years

Recent research highlights a significant link between Earth’s geological activities, like plate tectonics and river movements, and the evolution of biodiversity, offering a comprehensive view of how life has been influenced over 500 million years by Earth’s physical evolution.

Recent research reveals a striking correlation to how life evolved over 500 million years.

The movement of rivers, mountains, oceans, and sediment nutrients at the geological timescale are central drivers of Earth’s biodiversity, new research recently published in Nature reveals. The research also shows that biodiversity evolves at rates similar to the pace of plate tectonics, the slow geological processes shaping continents, mountains, and oceans.

“That is a rate incomparably slower than the current rates of extinction caused by human activity,” said lead author Dr Tristan Salles from the School of Geosciences.

The research looks back over 500 million years of Earth’s history to the period just after the Cambrian explosion of life, which established the main species types of modern life.

Rivers: Earth’s Circulatory System

Dr Salles said: “Earth’s surface is the living skin of our planet. Over geological time, this surface evolves with rivers fragmenting the landscape into an environmentally diverse range of habitats.

“However, these rivers not only carve canyons and form valleys, but play the role of Earth’s circulatory system as the main conduits for nutrient and sediment transfer from sources (mountains) to sinks (oceans). While modern science has a growing understanding of global biodiversity, we tend to view this through the prism of narrow expertise,” Dr Salles said. “This is like looking inside a house from just one window and thinking we understand its architecture. Our model connects physical, chemical, and biological systems over half a billion years in five-million-year chunks at a resolution of five kilometers. This gives an unprecedented understanding of what has driven the shape and timing of species diversity,” he said.


Sediment Flux to Oceans and Diversity of Marine Species
Sediment flux to the oceans and diversity of marine animal families over the past 540 million years. The Pearson coefficient of 0.88 indicates a strong positive correlation between the two variables. The Cambrian explosion and Great Ordovician Biodiversification Event (GOBE), as well as the big five mass extinction events, are indicated. Cm, Cambrian; O, Ordovician; S, Silurian; D, Devonian; Carb, Carboniferous; P, Permian; Tr, Triassic;J, Jurassic; K, Cretaceous; Pg, Palaeogene; Ng, Neogene. Credit: Nature

The discovery in 1994 of the ancient Wollemi pine species in a secluded valley in the Blue Mountains west of Sydney gives us a glimpse into the holistic role that time, geology, hydrology, climate and genetics play in biodiversity and species survival.

Historical Perspective on Landscapes and Life

The idea that landscapes play a role in the trajectory of life on Earth can be traced back to German naturalist and polymath Alexander von Humboldt. His work inspired Charles Darwin and Alfred Wallace, who were the first to note that animal species boundaries correspond to landscape discontinuities and gradients.

“Fast forwarding nearly 200 years, our understanding of how the diversity of marine and terrestrial life was assembled over the past 540 million years is still emerging,” University of Sydney PhD student Beatriz Hadler Boggiani said.

“Biodiversity patterns are well identified from the fossil record and genetic studies. Yet, many aspects of this evolution remain enigmatic, such as the 100 million years delay between the expansion of plants on continents and the rapid diversification of marine life.”

A Unified Theory of Biodiversity

In groundbreaking research a team of scientists – from the University of Sydney, ISTerre at the French state research organization CNRS, and the University of Grenoble Alpes in France – has proposed a unified theory that connects the evolution of life in the marine and terrestrial realms to sediment pulses controlled by past landscapes.

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