“Oldest life may have thrived 4.3 billion years ago in undersea thermal vents.”
1 March 2017
The San Diego Union-Tribune
In early 2010, Nature had published a NASA -supported study that claimed a new bacterial species had been found in Mono Lake that could incorporate arsenic into is DNA. Later that same year, Nature published another paper refuting initial claim, stating arsenic lacks chemical properties that would allow it to be incorporated into DNA stably.
Nature had recently published an article which focused on the discovery of bacterial fossils found in Canada that are 4.3 billion years old. If the microstructures resembling biological origins are verified, scientists may have to rethink the time of the origin of life on Earth. Earth is roughly 4.5 billion years old, and if the fossilized structures are found to be biological, it would indicate life originated much earlier than we originally thought. The structures were found in what appeared to be hydrothermal vent remains. Researchers have concluded that the origin of life may have indeed begun in deep, dark, oxygen starved hydrothermal vents in oceans. They have argued that if the origin of life started in hydrothermal vents, there could be potential fossil evidence on Mars that would correlate to a period in time in which Mars and Earth both contained water at the same time. If they’re unable to find any fossils on Mars, they suggest that Earth was an exception to the origin of life. The subject is still touchy among different researchers. Some speculate that hydrothermal vents didn’t exist that long ago.
Relation to Class:
We have learned about extremophiles in class that can withstand extreme heat, extreme cold, high salinity, brackish water, anaerobic environments, etc. One of the coolest topics we covered in class was about the microbes that had been frozen in glacial ice, thawed, and thrived once again. Microbes are pretty neat in their abilities to adapt, thrive and persist for millions of years in various environmental conditions.
The search for extraterrestrial life is intriguing because if you have an open mind, there really isn’t any reason why there wouldn’t be life outside of our planet. The universe is a vast expanse and there are millions of other galaxies that we have yet to explore, or cannot explore because of distance. What I found interesting about this article, was the brief mention of bacteria in Mono Lake that were able to incorporate arsenic into their DNA published by Nature in early 2010. Later that same year, they published an article refuting what they had previously claimed to be accurate. I remember when the article first came out and I was really excited to learn of arsenic-incorporating bacteria in my hometown. I grew up in June Lake and Bishop, Ca and went to school in Lee Vining where Mono Lake happens to be located. I chose this article because it is relative to my hometown. If you’ve never been to Mono Lake, you should plan a visit.
I realized only after completing my summary of the article that Professor Leigh had mentioned a similar article earlier in the semester.
In what generation may we finally find the answers we’ve been seeking in regards to sufficient evidence of extraterrestrial life?
Mono Lake Sunset, Lee Vining, Mono County, California. Photo Credit of a Google Search. I haven’t been home in 4 years so I wasn’t able to get any good, recent photos for your viewing pleasure.