In many ways, Earth’s story for the past 550 million ... Around 6 million years ago, between the Miocene and Pliocene epochs—or more specifically, the Messinian and Zanclean ages—the ...

Carbon dioxide levels in the Earth’s atmosphere hit nearly 420 parts per million in 2021 — a level not seen in around four million years, since the mid-Pliocene Epoch, long before our own ...