Credit: Pixabay/CC0 Public Domain
Discover how the humble worm played a crucial role in shaping Earth’s biodiversity during a 30-million-year period of explosive evolutionary changes. Prehistoric worms and invertebrates digging and burrowing along ocean bottoms triggered a series of events that led to the release of oxygen into the ocean and atmosphere, marking the beginning of the Great Ordovician Biodiversification Event around 480 million years ago, as revealed by researchers from Johns Hopkins University in a study published in the journal Geochimica et Cosmochimica Acta.
Senior author Maya Gomes, an assistant professor in the Department of Earth and Planetary Sciences, expressed amazement at how such small creatures, now extinct, could have such a profound impact on evolutionary history. This groundbreaking research allows for a reexamination of early ocean chemistry and geological records.
To gain insights into how changes in oxygen levels influenced major evolutionary events, Gomes and her team updated models detailing the gradual increase in oxygen levels over millions of years. By studying the relationship between sediment mixing caused by digging worms and the formation of pyrite, a mineral crucial for oxygen buildup, they found that higher levels of pyrite were associated with increased oxygen levels.
The researchers analyzed pyrite samples from nine sites along a Maryland shoreline of the Chesapeake Bay to understand early ocean conditions. Sites with sediment mixing, even just a few centimeters deep, contained significantly more pyrite compared to sites without mixing or with deep mixing.
2024-06-02 08:00:03
Source from phys.org