Amazing stuff!
"... The scientists' findings challenge prior theories of why species have evolved over vast periods. According to Müller, the cycles are 36 million years long due to regular patterns in how tectonic plates are recycled into the convecting mantle ...
It is this geological clock, intertwined with sea-level changes, that shapes the evolution and extinction of marine species over millions of years. But it is far from being alone.
Scientists discovered evidence of another 62-million-year biodiversity cycle. This time, this cycle could be linked to shifts in carbon dioxide levels. ..."
"Movement in the Earth's tectonic plates indirectly triggers bursts of biodiversity in 36-million-year cycles by forcing sea levels to rise and fall, new research has shown. ...
As water levels rise and fall, different habitats on the continental shelves and in shallow seas expand and contract, providing opportunities for organisms to thrive or die. By studying the fossil record, the scientists have shown that these shifts trigger bursts of new life to emerge. ..."
As water levels rise and fall, different habitats on the continental shelves and in shallow seas expand and contract, providing opportunities for organisms to thrive or die. By studying the fossil record, the scientists have shown that these shifts trigger bursts of new life to emerge. ..."
From the significance and abstract:
"Significance
The evolution of life on Earth has changed dramatically at tens of million-year (Myr) time scales. However, the causal mechanisms of these biotic changes remain conjectural. Here, we show evidence of cycles of tens of Myr in marine animal fossil data over the last 250 Myr. We find similar, correlatable cycles in sea-level and Earth’s interior processes, suggesting that long-term marine biodiversity was paced by geodynamically driven global sea-level cycles. We argue that biotic diversity has fluctuated by quasi-cyclical continental flooding and retreat of the ocean, expanding and contracting ecological niches on shelves and on epeiric seas.
Abstract
The fossil record reveals that biotic diversity has fluctuated quasi-cyclically through geological time. However, the causal mechanisms of biotic diversity cycles remain unexplained. Here, we highlight a common, correlatable 36 ± 1 Myr (million years) cycle in the diversity of marine genera as well as in tectonic, sea-level, and macrostratigraphic data over the past 250 Myr of Earth history. The prominence of the 36 ± 1 Myr cycle in tectonic data favors a common-cause mechanism, wherein geological forcing mechanisms drive patterns in both biological diversity and the preserved rock record. In particular, our results suggest that a 36 ± 1 Myr tectono-eustatically driven sea-level cycle may originate from the interaction between the convecting mantle and subducting slabs, thereby pacing mantle-lithospheric deep-water recycling. The 36 ± 1 Myr tectono-eustatic driver of biodiversity is likely related to cyclic continental inundations, with expanding and contracting ecological niches on shelves and in epeiric seas."
Scientists discover 36-million-year geological cycle that drives biodiversity (Primary source) Tectonic changes alter sea levels that can create breeding grounds for life
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