Of course, it helps that we're very omnivorous. We eat almost anything. If it lives, we've eaten it at one time or another. More important, we've also shared it. Our sharing goes beyond food.
Most societies have taboos about mating across the lines of clan, ethnicity, or race.
But the important thing about those taboos is that we break them. Intermarriage is another kind of sharing that holds our species together. Sharing goes beyond food and beyond mating. We also share the techniques for gathering food and fulfilling other needs. One cichlid fish had to develop its own specialized jaw for crushing and eating snails.