What did humans begin studying to predict seasons and migrations of animals?

He seventeenth amendment to the us constitution calls for the direct election of all us senators. this means that the people of each state get to vote to decide who will be their two us senators. before this, the legislatures of each state chose the two us senators from that state with no direct involvement of the average voter. why would this amendment be considered a reform? how would it benefit the people? even today some people claim that the seventeenth amendment was a bad idea. what arguments could be made for reverting selection of us senators back to the state legislatures?

What is guaranteed by the 5th amendment

What principle did president truman invoke in sending u.s. troops into south korea without first asking congress to declare war?