In captivity, the tufted capuchin has been seen to manufacture stone tools that produced simple flakes and cores. Some of the capuchins even used these sharpened stones to cut (in a back-and-forth motion) barriers in order to reach food. The importance of this behavior is that it serves as evidence of "mechanical proclivity to modify stones by using behaviors already in the monkeys' repertoires", and this behavior is seen as a precursor to stone-knapping. This early and limited tool use behavior has been hypothesized as similar to pre-"Homo habilis" and that artifacts of that time would probably resemble those of capuchins.