Anachronisms in the Book of Mormon 1000 years before the Jaredite record in the Book of Mormon begins. The main point of contention is how late these animals were present in the Americas before becoming extinct. Various Mormon authors have cited evidence that North American mound-builder cultures were familiar with the elephant. The oldest mound-builder societies date to around 2000 BC. The mound builder/elephant controversy did not originate with the Book of Mormon. In "The Mound Builders, Their Works and Relics", author Stephen Dennison Peet cites instances of exhumed mastodon remains and arguments given for why the remains were believed to be contemporary with mound builders.
Mastodon and expanded to relatively large numbers 13,000 years ago, and their hunting may have caused a gradual attrition of the mastodon population. Analysis of tusks of mastodons from the American Great Lakes region over a span of several thousand years prior to their extinction in the area shows a trend of declining age at maturation; this is contrary to what one would expect if they were experiencing stresses from an unfavorable environment, but is consistent with a reduction in intraspecific competition that would result from a population being reduced by human hunting. Mastodon Mastodons (Greek: μαστός "breast" and ὀδούς, "tooth")