Geography and Ecology of the Paleozoic

This chapter explores earth's history and divides it into the Precambrian and the Phanerozoic. No life was present during the first part of the Precambrian, informally known as the Hadean, while the Phanerozoic represents the last 540 million years of Earth's 4-billion-year history. Yet it is from this time that most multicellular life is known. The chapter details the three eras of the Phanerozoic: Paleozoic, Mesozoic, and Cenozoic. The continental blocks move over time, and their positions affect how heat is transferred via oceanic circulation, and also whether there is ice at the poles. The chapter talks about the Paleozoic continents, which were initially widespread, but by the end of the period they came together and formed the supercontinent Pangaea.