Late Carboniferous and Early Permian insect orders include both extant groups, their stem groups, and a number of Paleozoic groups, now extinct. During this era, some giant dragonfly-like forms reached wingspans of 55 to 70 cm (22 to 28 in), making them far larger than any living insect. This gigantism may have been due to higher atmospheric oxygen levels that allowed increased respiratory efficiency relative to today. The lack of flying vertebrates could have been another factor. Most extinct orders of insects developed during the Permian period that began around 270 million years ago. Many of the early groups became extinct during the Permian-Triassic extinction event, the largest mass extinction in the history of the Earth, around 252 million years ago. COUNT 10
QSN1 In addition to Carboniferous, what other insect order is inclusive of extant groups, stem groups and Paleozoic groups? ANS1 Early Permian QSN2 To what measurement, in cm, did the wingspans of giant dragonfly-like forms reach? ANS2 55 to 70 QSN3 Higher levels of what substance possibly contributed to the phenomenon of gigantism?  ANS3 oxygen QSN4 How many million years ago is the Permian period believed to have begun?  ANS4 270 QSN5 The most significant mass extinction of insect groups is commonly ascribed to what period? ANS5 Permian-Triassic QSN6 Late Caboniferous and Early Permain are what kind of orders? ANS6 insect orders QSN7 The insect orders include both of what? ANS7 extant groups QSN8 The insect orders include a number of what kind of groups? ANS8 Paleozoic groups QSN9 What kind of giant insect form had wingspans? ANS9 dragonfly-like forms QSN10 How wide were the wingspans of the dragonfly-like forms? ANS10 55 to 70 cm