Collegiate athletics have deep significance in Texas culture, especially football. The state has twelve Division I-FBS schools, the most in the nation. Four of the state's universities, the Baylor Bears, Texas Longhorns, TCU Horned Frogs, and Texas Tech Red Raiders, compete in the Big 12 Conference. The Texas A&M Aggies left the Big 12 and joined the Southeastern Conference in 2012, which led the Big 12 to invite TCU to join; TCU was previously in the Mountain West Conference. The Houston Cougars and the SMU Mustangs compete in the American Athletic Conference. The Texas State Bobcats and the UT Arlington Mavericks compete in the Sun Belt Conference. Four of the state's schools claim at least one national championship in football: the Texas Longhorns, the Texas A&M Aggies, the TCU Horned Frogs, and the SMU Mustangs.