*Leaf-cutting ants use tactile cues to determine the size of leaf pieces they cut, according to a new study.*

The ants, which are native to Central and South America, use their mandibles to cut circular pieces out of leaves, which they then carry back to their colonies. The size of these leaf pieces is important, as it affects the efficiency of the ants' foraging.

*To investigate how leaf-cutting ants determine the size of leaf pieces, researchers from the University of São Paulo in Brazil conducted a series of experiments.*

In one experiment, the researchers presented ants with leaves of different sizes. They found that the ants cut smaller pieces from larger leaves and larger pieces from smaller leaves. This suggests that the ants are using the size of the leaf as a cue to determine the size of the leaf piece.

In another experiment, the researchers attached small weights to the tips of the ants' mandibles. They found that the ants cut smaller pieces when they were carrying weights, suggesting that the ants are also using the weight of the leaf piece as a cue to determine its size.

*The researchers believe that the ants' ability to gauge the size of leaf pieces is an important adaptation that helps them to forage efficiently.*

By cutting pieces that are the right size, the ants can minimize the amount of time and energy they spend foraging, and they can maximize the amount of food they bring back to their colonies.

The study was published in the journal "Biology Letters."