Scientists from UCLA have discovered a deep-sea microorganism that's the same today as it was two billion years ago. It's an observation that actually bolsters Darwin's theory of natural selection, while offering the most extreme example of evolution's "null hypothesis."
About 2.3 billion years ago, Earth underwent what is known as the Great Oxidation Event, as early lifeforms photosynthesized enough oxygen that the gas took hold as a dominant part of our atmosphere. This massive shift allowed for the evolution of pretty much all complex life... but its roots go back far earlier than…
About 2.5 billion years ago, our planet had virtually no oxygen, and lifeforms were primitive. Then, oxygen levels suddenly spiked, the entire landscape of the planet changed, and we were on our way to complex life. Now, at last, we know why.