According to fossil records, the horses that lived 50 million years ago were much smaller, weaker and slower than modern horses. Which process is most likely responsible for the changes that have led to the increased size, strength, and speed in horses?
evolution by natural selection
Natural selection is the mechanism of evolution, where animals that are more “fit” for a certain environment will naturally be selected to reproduce more often. Over time, new species have evolved from similar ancestral species.
Take more free practice tests for other GED topics with our ged test online