The Meganisoptera, the taxonomic order of remarkably large but now extinct odonates that thrived during the Carboniferous period, included species with wingspans measuring up to 75 cm. Arthropleura, a now extinct genus of Carboniferous period arthropods related to modern millipedes, included members that could reach two and a half meters in length. So why aren’t there any arthropods of such great sizes any longer?
Why certain animals are the sizes they are – or aren’t – in different periods of the planet’s history is one of the many fascinating topics Graeme D. Ruxton addresses in his forthcoming book Nature’s Giants; The Biology and Evolution of the World’s Largest Lifeforms. “Through a diverse array of examples, from huge butterflies to giant squid, Ruxton explores the physics, biology, and evolutionary drivers behind organism size.”
