This is easily the oldest fossil we’ve ever featured. This small, dark rock is a stromatolite, a sedimentary rock consisting of layer upon layer of oxygen-producing microorganisms. These single-celled microbes were so simple they lacked a DNA packaging nucleus, but were responsible for possibly the most drastic changes the earth has undergone. By producing oxygen as a waste product, they were the only major source of atmospheric oxygen at the time, and therefore critical for the development of more complex life.
• Some stromatolites date back an astounding 3.4 billion years, making them the oldest record of life on planet Earth.
• When these microbes lived, Earth’s atmosphere had no oxygen, the oceans were euxinic—void of oxygen and rich in hydrogen sulfide (H2S).
• This specimen is from the Ord Ranges of Western Australia.
• These microbes oxygenated Earth and made it habitable for life as we know it.
• Add this artifact to your fossil collection.