Three hundred million years ago, giant insects like Meganeuropsis permiana, which resembled large dragonflies, thrived in the late Palaeozoic era. Scientists once believed these insects needed high oxygen levels to survive due to their less efficient breathing systems compared to mammals. This idea, known as the “oxygen constraint hypothesis,” suggested that as atmospheric oxygen decreased, giant insects couldn’t survive. However, recent research challenges this theory. Insects breathe through a tracheal system, where air enters through spiracles and travels through tubes to reach tissues. The hypothesis argued that larger insects would struggle with oxygen diffusion, but this explanation is now considered incorrect. Understanding how these ancient insects breathed helps us learn about evolution and adaptation.
QUESTION: How might understanding the breathing systems of ancient insects influence the way we think about the adaptability of modern species to changing environments?
Explanation for why we don’t see two-foot-long dragonflies anymore fails
