There are few things more characteristically – even exceptionally – human than concern for the suffering of beings unlike us. Compassion toward other species is rare in the animal world. To be sure, there are examples of “mutual altruism” where both species benefit – for example, cleaner fish that remove parasites from larger fish and obtain a meal for themselves in the process. But this is not compassion; both fish get something out of it. Only rarely will an animal sacrifice a resource or opportunity to help an individual of another species. It occasionally happens – there are remarkable anecdotes of sperm whales nurturing disabled dolphins or leopard mothers adopting baby baboons. But these are the exceptions that prove the rule.

Should animals have the same rights as humans?