Maneater includes a curious development system, in which you accrue levels in order to advance in age, but occasionally have to fulfill other conditions as well.
It’s a huge day in the life span of any shark, however, it will not just happen on its own. Even after you have reached the required degree, you will not automatically turn elder. Going to the grotto will not help, either. Rather, what you have to do would be to progress the most important story until a mission pushes you into another stage.
Basically, just keep playing the sport and you’ll get there. Just doing a little more story assignments, eating a few more unsuspecting people and generally doing shark things helps.
If you are can’t think of any shark things to do while you’re waiting to hit that cap, develop and become a real boy, we’ve got some suggestions. You could try to elevate your infamy position and combat some fancy bounty hunters. Landmarks are particularly helpful, since they unlock a few fine evolutions, and a number of them are interesting references to fun items. There is plenty to do, though the game clocks in at around ten hours for the average player.