Until 12 years ago, the scientific consensus was that humans were “nasty” at the core but had developed a veneer of morality. However, recent biological studies have overturned this view claiming that human children and most higher animals are capable of cooperating with one another.

According to Frans de Waal, a biologist at Emory University in Atlanta, the common scientific argument that morality is absent in nature and something created by humans is no longer relevant if we are to consider recent research.

Speaking at the annual meeting of the American Association for the Advancement of Science, he said that human children – and most higher animals are “moral” in a scientific sense, because they need to cooperate with each other to reproduce and pass on their genes.

He explained his theory by showing the audience videos from laboratories revealing the dramatic emotional distress of a monkey denied a treat that another monkey received; and of a rat giving up chocolate in order to help another rat escape from a trap. According to De Waal, this shows that animals naturally have pro-social tendencies for “reciprocity, fairness, empathy and consolation.”

De Waal’s theory that humans are naturally moral debunks a common belief that has been dominant in the science comunity since the 19th century.