Most evolutionists believe the wooly mammoth (Mammuthus primigenius) was extirpated from mainland Eurasia and North America approximately 10,000 years ago, with the last individuals surviving on Wrangel Island until 3,700 years ago. Similarly, the American mastodon (Mammut americanum) is believed to have gone extinct circa 10,000 years ago. This paper examines the hard data conflicting with these interpretations, including an Egyptian painting of a dwarf mammoth, surviving mastodon intestinal bacteria, sedimentary ancient DNA, and datable artifacts portraying proboscideans. This evidence suggests that mammoths and mastodons survived much later than evolutionists believe, perhaps as late as 800 years ago. It is concluded that the evolutionists’ estimates for the extinction dates of mammoths and mastodons are in error, which not only affects their timescale but also creates problems for their hypotheses on the causes of the endPleistocene extinction event.