Mastodon group consisted of adult females and young, living in bonded groups called mixed herds. The males abandoned the mixed herds once reaching sexual maturity and lived either alone or in male bond groupings. As in modern elephants, there probably was no seasonal synchrony of mating activity, with both males and females seeking out each other for mating when sexually active. Mastodons have been characterized as predominantly browsing animals. Most accounts of gut contents have identified coniferous twigs as the dominant element in their diet. Other accounts (Burning tree mastodon) have reported no coniferous content and suggest selective feeding on low,
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")