if a gorilla trys to grapple with out the improved grapple feat dose it still provoke?
yes.
whay if he is under the effetc of http://www.d20pfsrd.com/classes/core-classes/barbarian/rage-powers/paizo--- rage-powers/body-bludgeon-ex
rage power?
can you use links in the future please? Or quote the text?
But yes, it'll still provoke on the initial grapple attempt, even with that rage power.
A gorilla would, but a gorilla bear would not, provided it utilized the grab as part of the special parameter of it's natural attack.
Furthermore, attacking with the body bludgeon rage power would not provoke an AoO.
Though the initial grapple attempt would provoke, provided you lack the improved grapple feat.