
Kathryn E. answered 05/25/19
BA in Anthropology
Honestly, I’m certainly not an expert on this subject, and I think you’re possibly asking about a long process of one species living with another in some kind of symbiotic relationship that changes over time. But on a much smaller scale, examples of cross-species relationships seem to happen rather often, as when a mother mammal adopts a baby of another species, maybe nurses it and raises it as her own. (Romulus and Remus and their mother the wolf?) And a famous gorilla in Atlanta, whose name I don’t remember, had a beloved pet kitten. Birds following herd animals can serve as sentinels to warn of approaching marauders.