In Africa, elephants are keystone players;as they move through an area, their knocking down trees and trampling create a habitat in which certain plants and animals can flourish.

• 在非洲，大象也扮演关键角色，牠们迁移时会推倒大树、四处践踏，有些动植物便在此环境繁衍，等于是大象创造出新的栖地。