The Evolution Series is a line of diesel locomotives built by GE Transportation Systems, initially designed to meet the U.S. EPA's Tier 2 locomotive emissions standards that took effect in 2005. The first pre-production units were built in 2003. Evolution Series locomotives are equipped with either AC or DC traction motors, depending on the customer's preference. All are powered by the GE GEVO engine.
The Evolution Series was named as one of the "10 Locomotives That Changed Railroading" by Trains Magazine and was the only locomotive series introduced after 1972 to be included in that list.
The Evolution Series locomotives are some of the best-selling and most successful freight locomotives in United States history.