Mesozoic
Naming

The phrase "Age of Reptiles" was introduced by the 19th century paleontologist Gideon Mantell who viewed it as dominated by diapsids such as Iguanodon, Megalosaurus, Plesiosaurus, and Pterodactylus.

The current name was proposed in 1840 by the British geologist John Phillips (1800–1874). "Mesozoic" literally means 'middle life', deriving from the Greek prefix meso- (μεσο- 'between') and zōon (ζῷον 'animal, living being'). In this way, the Mesozoic is comparable to the Cenozoic (lit. ' new life ') and Paleozoic ('old life') Eras as well as the Proterozoic ('earlier life') Eon.

The Mesozoic Era was originally described as the "secondary" era, following the "primary" (Paleozoic), and preceding the Tertiary.
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