5. India
India is a part of the old supercontinent of Gondwana that has joined Eurasia. India separated from the rest of Gondwana over a hundred million years ago, and until it collided with Eurasia, about fifty million years ago, it was an island. This is reflected in that the Indian subcontinent is a peninsula, not a land bridge. There are nevertheless some broad physical similarities with the Near East. Like the southern Near East, India overall is relatively flat. Inland from the coastal plains of the south there are mountain ranges arising from the rifting that brought the region into being, and between them are the highlands of the interior. But there is nothing in the south to compare in altitude to the combination of mountains and plateau by which India is closed off to the north. Much as in the northern Near East, this massive uplifting is the product not of rifting but of collision. Yet the scale of the uplifting dwarfs anything the Near East has to show; indeed, there may have been nothing on earth to match it in the last half billion years. By contrast, it is between the northern mountains and the southern highlands that India is at its lowest and flattest, with alluvial plains comparable to those of Mesopotamia.
One of the most significant differences between India and the Near East is climatic: India gets much more rain. The high terrain to the north and the open ocean to the south generates the monsoon, the wet summer so alien to the Near East. But the distribution of summer rainfall in India is very uneven. The wettest regions are the coastal strip in the southwest and a large area in the northeast; by contrast, the southern highlands are dry, and the northwest shares the aridity of the Near East, of which it is in effect a climatic extension. As a result, the two great rivers that rise in the northern mountains have somewhat different effects on the lands through which they flow. Both of them deliver a valuable agricultural resource, namely silt. But in the northeast the Ganges takes its water to a jungle region of abundant rainfall; whereas in the northwest the Indus brings life to a land much of which would otherwise be desert.