Grumpy? You clever clogs
PEOPLE who are tetchy, aggressive and possess a short fuse may be more grumpy because they are higher up the evolutionary scale.
Where adults have a more childlike, sweet-natured attitude, it could be a sign that they have not developed as far, says a new study.
The claims will no doubt delight bad-tempered TV chef Gordon Ramsay and Sir Alan Sugar, star of The Apprentice.
Researchers ran a series of skills tests comparing chimpanzees to easy-going bonobo apes, both close genetically to human beings.
Even very young chimps were quicker than their bonobo cousins.
But they were also much more aggressive, said a team from Harvard University for the online journal Current Biology.