"Spiders were around long before humans, and it is likely they will be around in some number far into the future, even if humans are not. When most land and sea animals died out during the Permian mass extinction, spiders survived. Spiders thrived when oxygen levels were both lower and higher than today, when the sunlight hitting the ground was both stronger and weaker, and when plant and animal populations were both greater and smaller. Silk and the evolvable nature of the genes that dictate it have enabled spiders to stake a claim on the land for hundreds of millions of years and they are likely to do so for hundreds of millions of years to come."