How did plants respond to past climate change?

Scientists studied the number of stomata—the tiny pores on leaves that exchange CO2 and H2O—to figure out how plants responded to climate change in the past. Major drops in the number of stomata on leaves coincide with mass extinction events.

This is because plants track the CO2 levels in the atmosphere pretty well. When there’s lots of it in the atmosphere, they can make do with fewer stomata, conserving water loss through transpiration in the process. Read more in this post I wrote for The STEM Times.

Beautiful image of stomata captured by the talented Fernan Federici.