The Isthmus Of Panama
Oceans and seas, and mountains, can divide ecozones. If those arent options, then Deserts is another answer
A river
The Lombok Strait
The Isthmus of Panama
Oceans and seas, and mountains, can divide ecozones. If those arent options, then Deserts is another answer
The Sahara Desert.
There are multiple ecozones in the western hemisphere, but some are larger than others. The Boreal Shield and the Taiga Shield are two of the major ecozones in the western hemisphere.
Ecozones are defined as having specific lifeforms that differ from the adjacent zone.
Palearctic and Afrotropic.
Desert and Oceans
Two neighboring ecozones would be defined by having different plants and animals.