To see the importance of its society to a social animal, look at the often sorry stories of those which are taken out of their natural communities.
In 1979 an orca called Keiko (“lucky” in Japanese) was captured at the age of about two off Iceland.
He was shunted from one aquarium to another before ending up in a tank in Mexico City with no other members of his species for company. There he starred in a popular film, “Free Willy”, about the capture and eventual happy release of an orca.
The film led to the setting up of the Free Willy-Keiko Foundation. Keiko was flown back to Iceland and put into a sea pen to get the hang of being wild again. But he never learned to hunt or interact with other killer whales—he would swim to the nearest boat if they approached him.
When he was finally released, he followed a pleasure boat up a Norwegian fjord and stayed there. Eventually the foundation built another sea pen for him in the fjord, and he lived out his life as he had lived before the film, dependent on people for his food and care.
Off Laguna, in southern Brazil, people and bottlenose dolphins have fished together for generations. The dolphins swim towards the beach, driving mullet towards the fishermen.
The men wait for a signal from the dolphins—a distinctive dive—before throwing their nets. The dolphins are in charge, initiating the herding and giving the vital signal, though only some do this.
The people must learn which dolphins will herd the fish and pay close attention to the signal, or the fishing will fail.
Both groups of mammals must learn the necessary skills. Among the humans, these are passed down from father to son; among the dolphins, from mother to calf.
In this example, how much do the species differ?