I want to say animals, but I'm leaning towards the elders of the tribes.
Answer:
The tenth Amendment
Explanation:
This amendment states that powers not given to the granted by the constitution or powers prohibited by the states is granted to the people/citizens of the states. I.e Not all powers of the state government is granted to the federal government but only the states inhibits this law and the state citizens.
Im not sure what the question is revolving this statement, but it is true and all lands will develop differently due to its geographic landscape
Senators serve for 6 years at a time, I believe is the answer you're looking for.