At the end of chapter 9, Pi talks about the zoo that his family used to run. He says that his father, as a zookeeper, had "an intuitive gift" and that this "gift" made up for a "lack of formal training." The implication here is that although Pi's father was not formally trained or taught how to be a good zookeeper, he managed to be one anyway because he had a natural affinity with animals. Elaborating upon what exactly his father's "gift" was, Pi says that his father "had a knack for looking at an animal and guessing what was on its mind."
Pi's father's gift suggests that perhaps deep down, on a primal, instinctive, elemental level, all humans have this natural affinity with animals. In an evolutionary sense, perhaps the suggestion is that this affinity dates back to a time when we were all uncivilized animals, all foraging and hunting for food, all relying upon the same basic instincts that the animals in our care rely on today.
One of the key ideas in Life of Pi is that all living beings, humans and animals included, are connected. This idea is something like the idea of a universal consciousness, as proposed by psychoanalyst Carl Jung. This idea proposes that on some deep, irreducible level, all living beings are connected, because all living beings are part of a greater, cosmic consciousness. Pi's father's "gift," looked at in this light, possibly points towards this idea, suggesting that the affinity between humans and animals is just one aspect of a greater affinity between all living things.