Answer: When studying the museum’s collection of plant fossils for information about the climate, Wing and Barclay start with plant leaves.
Roughly 56 million years ago, during a time called the Paleocene Eocene Thermal Maximum (PETM), Earth’s average temperature rose four to eight degrees Celsius in less than 10,000 years. The cause was geologic processes releasing trillions of tons of carbon dioxide into the atmosphere. The dramatic shift in global climate forced massive upheaval in ecosystems around the world.
“It’s the best analogue for the climate change we’re experiencing today,” Barclay said.
Fossil plants and their leaves from the PETM show that ecosystems shifted massively because of the rapid increase in global temperature. But global warming during the PETM did not come from humans. So, scientists today are working on ways to extrapolate information from that period and apply it to the even faster and more drastic events of today.
