Abstract
Experimental evolution has provided novel insight into a wide array of biological processes. Species in the genus Tetrahymena are proving to be a highly useful system for studying a range of questions using experimental evolution. Their unusual genomic architecture, diversity of life history traits, importance as both predator and prey, and amenability to laboratory culture allow them to be studied in a variety of contexts. In this paper, we review what we are learning from experimental evolution with Tetrahymena about mutation, adaptation, and eco-evolutionary dynamics. We predict that future experimental evolution studies using Tetrahyemena will continue to shed new light on these processes.