When traveling from the North Pole to the equator, the successive biomes (tundra, coniferous forest, temperate deciduous forest and tropical rainforest) change based on which primary factors?
1) A decrease in annual temperature and a decrease in sunlight
2) An increase in annual temperature and decrease in precipitation
3) Succession of organisms in the ecosystem
4) An increase in annual temperature and precipitation
5) An increase in annual amount of smoking