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 (steam locomotive) the engine, where more than 20 copies were produced; these were identical except for having their cylinder bore increased to (from "Mastodon"'s ). The success of this engine inspired railroad president Leland Stanford to instruct Stevens to build an even larger locomotive, which would be the largest the world had ever seen up until that time. This engine, a 4-10-0 named "El Gobernador" (CPRR #237), looked virtually identical to "Mastodon", with the exception of being longer and having an additional pair of driving wheels. Unfortunately, this engine, unlike its predecessor, was doomed to failure. Sometime in the early 20th century,