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this time were quite literally capable of walking all over the Earth, f and in reflection of this it appears to be the case that the fossil £

remains of rather similar types (theropods and prosauropods) have | been found on nearly all continents. s

During subsequent Periods, the Jurassic (Figure 32b) and Cretaceous (Figure 32c), it is evident that the supercontinent began to fragment as the immensely powerful tectonic conveyor belts imperceptibly, but remorselessly, wrenched Pangaea apart. The end product of this process at the close of the Cretaceous was a world that, though still different geographically (note particularly the position of India in Figure 32c), has some very familiar-looking continents.

The earliest dinosaurs seem to have been able to disperse across much of Pangaea, judging by their fossils. However, during the Jurassic and subsequent Cretaceous Periods it was clearly the case

32. The changing continents. a. Triassic Period showing the single supercontinent called Pangaea. b. Middle Jurassic Period. c. Early Cretaceous Period. Note that the dinosaur images become increasingly different as the continents separate from one another.

32(d). The continents as they are today. Close the Atlantic Ocean and the Americas fit neatly against West Africa.

that the unified supercontinent became gradually subdivided by intervening seaways as continent-sized fragments gradually drifted 0 apart. |

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