Ants Can Associate a Symbol with a Number of Elements Through Conditioning

On the basis of the known numerosity abilities of the ant Myrmica sabuleti, it was checked if workers of this species could associate a symbol with a number of elements through conditioning, an ability rarely encountered in invertebrates and never mentioned in ants. Working each time on two colonies, we observed that these ants could associate a particular shape used as a symbol with 1, 2, 3 or 4 displayed dots. This acquired association was only slightly affected by a change in shape, color or size of the sighed elements. This elementary association of a symbol with a number by an ant has also been observed in bees, while vertebrates such as birds and monkeys can bring this ability at a more complex level.