The ancestors of elephants inhabited every continent expect antarctic and australia. but the asian and african elephants are the only one to survive. why?

Because of their biological point of view which showing their structural resemblance (morphological resemblance) and can interbreed under natural conditions(favour condition) which allow them to produce fertile offspring freely.that's why Asian and African elephants have capable to survive.

Because the people in antartic and australia dont care for nature

Iguess i would say diagrams would be most difficult subject too correct