Final answer:
Evolutionary Significant Units (ESUs) are populations or groups of organisms that are distinct and important in terms of their evolution. They are identified based on genetic differences and their ecological and evolutionary significance. ESUs are used to protect unique and potentially endangered populations of species.
Step-by-step explanation:
The term Evolutionary Significant Units (ESUs) refers to populations or groups of organisms that are considered distinct and important in terms of their evolution. These units are often defined based on genetic differences and their ecological and evolutionary significance. ESUs are used to identify and protect unique and potentially endangered populations of species.
For example, in the case of salmon, different populations may have distinct genetic characteristics and may migrate to different locations for spawning. These populations can be considered ESUs, as their genetic differences indicate separate evolutionary lineages.