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 (band) audience. Drummer Brann Dailor sings lead vocals for the verses of the song "Oblivion". Mastodon was a headliner at the Scion Rock Fest on February 28, 2009, performing a set containing three tracks from "Crack the Skye", the first time these songs were played since being finalized and recorded. On May 15, 2009, Mastodon performed a shortened version of "Oblivion" on the "Late Show with David Letterman". In order to support their new album, Mastodon toured with Metallica on the latter part of the 2009 European leg of their World Magnetic Tour. In Fall of 2009, they embarked with Dethklok