Complex sentence: Thornwell Jacobs chose an unusual mascot to represent Oglethorpe's athletic teams: the Stormy Petrel, a seabird said to have been admired by James Oglethorpe for its hardiness and courage.
Split into simpler sentences: Thornwell Jacobs chose an unusual mascot to represent Oglethorpe's athletic teams. The university's mascot is the Stormy Petrel, a seabird said to have been admired by James Oglethorpe for its hardiness and courage.