Pi uses the structure of religious ritual and scientific study in order to survive. This is part of his maturity. But, he also had to compromise some of his values by eating human flesh and becoming a carnivore. Maturing is certainly becoming more responsible but it is also a willingness to change, and Pi was up to the challenge; even if it meant abandoning some of hisvalues. He was willing to change. In fact, in efforts to stop people from calling him “Pissing” when he was young, Pi changed his name to Pi. So, this question of changing his identity had actually been something he had already embarked upon.
Pi develops a keen eye for detail in carrying out his daily routine. He did this to survive but it also made him more sensitive to his surroundings.
Pi previously described how different animals could adapt to each other and live together. He also remembered his father’s warning of zoomorphism; that it is dangerous to think of another animal as a human. Pi heeds this warning, but it doesn’t mean he can’t adapt to living with the animals on the raft as if they were his family.
You could make the case that his adapting and forming an imaginatively unusual family on the raft also matured him and prepared him for getting along with humans later in his life. Here we see the duality of Pi but in a more mature light: He is religious and scientific. He is intelligent enough to treat animals like animals, but adaptive enough to live with them as if they were family. He learns what many adults actually do not. Forgive the cliché, but the world is not black and white. He can be both spiritual and scientific. He can go through suffering struggles and create a narrative to help him understand it. He is able and willing to change and adapt. Just think of how he embraced multiple religions. He is open-minded and he physically and mentally proves this during his time on the raft.