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Monkeys can use symbols to add, a new research has found. The findings of the research shed light on the evolutionary origins of math, according to researchers.

Researchers have long known the fact that humans possessed a sophisticated combination of mathematical capabilities that are unmatched in animal kingdom. However, there are increasing evidences that some of these capabilities are also shared by other species. 

To test the extent of such capabilities scientists considered a relatively distant relative of humans: rhesus monkey. 

"You would have trouble distinguishing 'oo o ooo ooo ooo ooo oo ooo' [a string of 20 symbols] from 'o ooo oooo oo oooo ooo ooo o' [a string of 21 symbols], but if I asked you whether 20 was larger or smaller than 21, you could answer faster and more accurately," said lead study author Margaret Livingstone, a neuroscientist at Harvard University Medical School, in the press release. 

Scientists taught three rhesus monkeys the value of 26 distinct symbols which included 10 Arabic numerals and 16 letters. Each symbol was associated with zero to 25 drops of a reward of water, juice or orange soda. 

Researchers noticed that given the choice of two different symbols, the monkeys chose the symbol that represented the larger reward with more than 90 percent accuracy, suggesting the fact that monkeys learned to distinguish the symbols and assigned them values. 

"The monkeys want the most of whatever is out there, and this is just one of many ways to figure out the best way to get the most," said Livingstone. 

"They turned out to be like us - more accurate when values were represented by symbols than by the number of dots," Livingstone added. "It tells us what good symbols are."

"The monkeys did not memorize the addition of pairs of numerals; they just fairly accurately combined two symbols."

Researchers have detailed their findings online in the journal Proceedings of the National Academy of Sciences.