Morgan, who was released along with offensive lineman Daniel Baldridge, played 39 snaps in four games this season and logged one tackle in the process.
Davis was an undrafted free agent out of Bethune-Cookman where he collected 22 career sacks. He has been on the team's practice squad for the first four weeks of the season.
Spurlock has played in 46 career games with one start in campaigns with the Arizona, Tampa Bay, San Francisco and San Diego. He has brought two kickoffs and a punt back for touchdowns and has 23 receptions for 294 yards and two receiving touchdowns over his five-year career.
Spurlock is expected to provide depth with Laurent Robinson sitting due to a concussion. The Jaguars are hoping that Davis can provide a boost to a pass rush that ranks dead last in the NFL with two sacks.