<i>Cebus apella</i> group. Capuchin Monkeys Sharing
(Photo courtesy of Frans de Waal.)
CC BY 2.5
Powell K: <i>Economy of the Mind.</i> PLoS Biol 1/3/2003: e77. <a rel="nofollow" class="external free" href="https://dx.doi.org/10.1371/journal.pbio.0000077">https://dx.doi.org/10.1371/journal.pbio.0000077</a>