Ed Davis was not 215 lb last year
Ed Davis weighted 227 lbs at the draft combine so unless he lost about 12 pounds during last season. A season where he was injured for most of it. Spent most of the time working out cause he couldn't put any pressure on his knee, so technically he only gained 8 pounds. Its probably all muscle looking at this footage from this summer.
His number 34 in white and than number 33 in red
http://www.youtube.com/watch?v=7lnw0CnkROA
His Draftexpress profile showing his weight after the draft combine
http://www.draftexpress.com/profile/Ed-Davis-1354/