The worlds population is distrubted on earths surface by

The world's population is distributed by population density. 

The world's population is distributed on the earth's surface mostly either within the temperate zone or the tropics and to some extent deserts like in parts of California, the US SW, Mexico and Chile and the Middle East. The temperate zone would include such countries as Canada, the US and much of Europe parts of Russia, and China. The tropics includes most of Africa, and much of Latin America plus New Guinea, Indonesia, etc. 

Is there a picture of the diagram?

Answer the zagros mountains, stretch across western iran and are located next to the khuzestan plain; answer( zagros mountains