Complex sentence: Grubbs, a former member of Squirrel Bait and Bastro, formed the band in Chicago in 1991, and they released their first album The Serpentine Similar in 1993.
Split into simpler sentences: Grubbs, a former member of Squirrel Bait and Bastro, formed the band in Chicago in 1991. Gastr del Sol released their first album The Serpentine Similar in 1993.