Scientists from Montana State University have uncovered new insights into how ancient microbes on Earth adapted to a world with increasing oxygen levels. Led by Professor Bill Inskeep, the research team studied microorganisms living in hot springs of Yellowstone National Park, shedding light on the origins of life on our planet.
The Great Oxidation Event around 2.4 billion years ago marked a significant change in Earth’s atmosphere, shifting from almost non-existent oxygen to the 20% we breathe today. To better understand this event, Inskeep and colleague Mensur Dlakic examined microbes living in two thermal springs – Conch Spring and Octopus Spring. The team chose these sites due to their contrasting environments: Conch Spring has higher oxygen levels than Octopus Spring.
The researchers focused on three types of thermophiles that thrive in both springs at temperatures up to 190°F (88°C). These microbes likely adapted first as oxygen levels increased, says Inskeep. They inhabit ‘streamers,’ thin structures that sway in the flowing hot water. The scientists discovered that streamers in Octopus Spring had a greater diversity of microbial life compared to Conch Spring.
Analyzing their genes, the researchers found that low-oxygen microbes in Conch Spring expressed highly active genes for survival in an oxygen-poor environment, while those in Octopus Spring expressed genes better suited for higher oxygen levels. This suggests they evolved to thrive as the atmosphere became richer in oxygen.
Inskeep and Dlakic’s work helps scientists understand how life adapted to Earth’s changing conditions over billions of years. Yellowstone provides a unique environment for this type of research due to its exact geochemical conditions, making it difficult to replicate in the laboratory. The study offers insights into the origins of life on our planet and how all living things evolved to survive.
Source: https://www.discoverwildlife.com/environment/thermophilic-microbes-yellowstone-national-park