As the resources in the world are distributed unequally, the crops and the ability to grow them in specific environmental conditions such as near the river valleys, on the foothills of the mountains and near the flood plains differ worldwide as many places don't have enough sunlight,
many places is too warm or hot for there growth and other place are too cold or are locates at great heights. Variation thus exists in the cropping patterns and the cropping intensity as they need specific conditions as climate, weather, and soil properties.
Many of the earlier civilizations developed and prospered near the river valleys.
He claimed that they were one large supercontinent called Pangaea. His evidence for his claim was that the general shapes of the separate continents and how they can fit together if you arrange them. He noticed patterns in the mountain ranges; when all the continents are together the ranges line up with one another.