Pages Give Air to Scorpions and Poetry to Peoples
"Book Lungs" are respiratory tissues used in the process of atmospheric gas exchange. Arachnids have book lungs. Scorpions and spiders and ticks. There is no other order of land-dwelling creatures that uses books for breath. Book lungs are quite literally an arrangement of page like sheets of hemolymph saturated tissues that collect as pages do into 'books'. Spiders and scorpions use these air/life 'books' to maximize the total surface area of hemolymphic tissues exposed to the air. Therefore it can be said that these 'books' optimally maximize (for spiders) the amount of gas exchanged with the environment. Modern arachnids have enjoyed this system of respiration without any determinable evolutionary changes for at least 410 million years.