In an amazing show of self-control, cuttlefish can resist the impulse to eat a morsel of food if it means getting to eat two morsels later on, a new study shows. In experiments, the marine molluscs passed a variation of the'marshmallow test' – originally used in the 1970s to measure a child's ability to delay gratification. In the original Stanford experiment, pre-school kids were given one marshmallow and told they could eat it straight away, or, if they waited 20 minutes, have two marshmallows instead. For this new study, scientists performed a'fishy version' of the legendary experiment using shrimp instead of marshmallows. They found the creatures could wait over two minutes to get their preferred type of shrimp – and that the cuttlefish that could delay gratification the longest were the most intelligent, as determined by a another learning task.

The folks who brought us the marshmallow test have some unlikely news: children today have more self-control than ever. That conclusion is based on more than 50 years of results from the iconic test, which allows a preschooler to eat one treat immediately or two if she can wait 10 minutes. The effort at delayed gratification is vastly funny but the results were found to have serious implications for children's future success. Led by psychologist Walter Mischel, who created the experiment -- one of the most famous in developmental psychology -- a research team found that children tested between 2002-2012 held out for two minutes longer on average than the original test-takers in the 1960s, and one minute longer than participants in the 1980s. A 4-year-old in the earliest group waited as long as a child between 2 ½ and 3 in the most recent tests, and 4-year-old test-takers in the 1980s waited as long as a child who was 3 ½ in the 2000s.

Willpower is a sign of high intelligence, and a new study shows some chimps have it. Just like in humans, the smartest chimps are typically better at exerting self-control and delaying gratification to receive a better reward later on, research found. Researchers hope to use this link to assess the role that willpower played in the evolution of humans. Willpower is a sign of high intelligence, and a new study shows some chimps have it. Professor Michael Beran, lead author of the study from Georgia State University, said: 'The fact that this link between self-control and intelligence exists in species other than humans may demonstrate an evolutionary basis for the role that willpower plays in general intelligence. 'Future research could clarify whether the relationship also exists in other primates and even non-primate species.'