Do monkeys, like humans, have hot-hand fallacy? Yes, reveals a new study.
Hot-hand fallacy is a belief that a person who has experienced success with a random event has a greater chance of further success in additional attempts.
The concept has been applied to gambling and sports.
Humans have a well-documented tendency to see winning and losing streaks in situations that, in fact, are random.
Now, researchers have found that monkeys also share our unfounded belief in winning and losing streaks.
The results suggest that the penchant to see patterns that actually don't exist may be inherited - an evolutionary adaptation that may have provided our ancestors a selective advantage when foraging for food.
The cognitive bias may be difficult to override even in situations that are truly random.
This inborn tendency to feel that we are on a roll or in a slump may help explain why gambling can be so alluring and why the stock market is so prone to wild swings, said co-author Benjamin Hayden.
To measure whether monkeys actually believe in winning streaks, the researchers had to create a computerised game that was so captivating that monkeys would want to play for hours.
"Luckily, monkeys love to gamble," said Tommy Blanchard from University of Rochester in the US.
So the team devised a fast-paced task in which each monkey could choose right or left and receive a reward when they guessed correctly.
The monkeys showed the hot-hand bias consistently over weeks of play and an average of 1,244 trials per condition.
"They had lots and lots of opportunities to get over this bias, to learn and change, and yet they continued to show the same tendency," Blanchard said.
The study was published in the Journal of Experimental Psychology: Animal Learning and Cognition.
