Should some of the most social, intelligent and charismatic animals on the planet be kept in captivity by human beings?

That is a question asked more frequently than ever by both scientists and animal welfare advocates, sometimes about close human cousins like chimpanzees and other great apes, but also about another animal that is remarkable for its intelligence and complex social organization — the killer whale, or orca.

Killer whales, found in all the world’s oceans, were once as despised as wolves. But in the last half century these elegant black-and-white predators — a threat to seals and other prey as they cruise the oceans, but often friendly to humans in the wild — have joined the pantheon of adored wildlife, along with the familiar polar bears, elephants and lions.

With life spans that approach those of humans, orcas have strong family bonds, elaborate vocal communication and cooperative hunting strategies. And their beauty and power, combined with a willingness to work with humans, have made them legendary performers at marine parks since they were first captured and exhibited in the 1960s. They are no longer taken from the wild as young to be raised and trained, but are bred in captivity in the United States for public display at marine parks.