4-12-09, Mastodon, House of Blues: Appraising the thinning headbanger manes assembled reverently around the House of Blues’ stage in anticipation of Mastodon’s Saturday night show, the metalheads in attendance weren’t getting any younger. Or, Mastodon’s prog leanings appeal most to an earlier generation of metal fan.
If the band’s name can call to mind any associations other than gargantuan guitar playing or stampeding lyrics, it is the long extinct ice age creature, the last great behemoth of another time, prescient enough to dull their sharp metallic edge with a imagistic mysticism (clips of overexposed Ingmar Bergman movies rolled on the screen behind them) that recalls such concept art as graced Live’s album covers.

Protected by menacing brambles of tattoos and Gwar T-shirts, the crowd only appeared unapproachable. These metal fans are a genial bunch of unassuming, Falstaffian pot smokers who like their rock ‘n’ roll sprinkled with a little gravitas.

They are all part of a dwindling heard that sprouted in the ’80s, flourished in the ’90s, and dipped to the fringe during the present decade. Most of them sit in stasis as functioning members of an ever-tempering society, but they are always ready to be thawed out and to thrive in the glow of Brann Dailor’s gleaming drum set, itself a steely obelisk to a bygone era of heavy metal.