The surface of the Earth plays a crucial role in connecting various systems and processes on our planet. Over time, this surface undergoes changes, with rivers shaping the landscape and transferring sediments from mountains to oceans. The influence of landscapes on the development of life on Earth has been recognized since the 19th century, but many aspects of biodiversity evolution remain unknown. In a recent study published in Nature, researchers propose a new theory that links the evolution of biodiversity over the past 540 million years to sediment “pulses” controlled by past landscapes.
To conduct their research, the scientists used a computer model based on an open-source code released earlier this year. They incorporated reconstructions of past climate and tectonics to simulate the evolution of landscapes over space and time. The results of their simulations were then compared to reconstructions of marine and continental biodiversity over the same period. The computational simulations required significant processing power and were equivalent to ten years of computational time.
The researchers discovered a positive correlation between sediment carried by rivers into the oceans and the diversification of marine life. They also found that episodes of mass extinctions in the oceans occurred after significant decreases in sedimentary flow, suggesting a link between nutrient deficiency and biodiversity destabilization. On land, the researchers observed a correlation between sediment cover and landscape ruggedness with plant diversification over the past 400 million years. They hypothesize that as the Earth’s surface became covered with thicker soil deposited by rivers, plants were able to develop and diversify.
Overall, the findings highlight the strong influence of landscape dynamics on the diversity of life on Earth. The interactions between tectonics, climates, sediment flows, and landscape changes play a crucial role in shaping biodiversity over long periods of time. The study also emphasizes that biodiversity has evolved at a much slower pace than the current rate of extinction caused by human activity.
