Evolutionary process whereby one species evolves into another without any splitting into multiple species Punctuated Equilibrium Model of the rate of evolution in which there are long periods of little change (stasis) in the species punctuated by short bursts of rapid change (usually due to an environmental change) Extinction. Rapid disappearance of a species.
17th Amendment to the U.S. Constitution: Direct Election of U.S. Senators. Americans did not directly vote for senators for the first 125 years of the Federal Government. The Constitution, as it was adopted in 1788, stated that senators would be elected by state legislatures.
This amendment shall not be so construed as to affect the election or term of any Senator chosen before it becomes valid as part of the Constitution. The 17th Amendment to the Constitution provides for direct election of Senators. Article. XVII Proposed 1912; Ratified 1913; Possibly Unconstitutional (See Article V, Clause 3 of the Constitution. The Senate of the United States shall be composed of two Senators from each State, elected by the people thereof, for six years; and each Senator shall have one vote.