@article {311013,
	title = {Possible causes of sex differences in the use of natural hammers by wild chimpanzees},
	journal = {Journal of Human Evolution},
	volume = {13},
	year = {1984},
	pages = {415 - 440},
	abstract = {<p>The wild chimpanzees of the Tai National Park, Ivory Coast, present an important sex difference in nut-cracking behavior: Adult females more frequently perform the two most difficult techniques, coula cracking in the tree and panda cracking. Adult females are more efficient than males in all the three nut-cracking techniques for one or the other measure of efficiency (number of hits/nut and number of nuts opened/min). The analysis of 5 hypotheses which may explain these differences, stresses the role of the difference of sociability and sexual dimorphism between the sexes, both negatively affecting the nut-cracking techniques and performance of the adult males. We shall discuss the role of these factors on the evolution of the division of labor and food-sharing in the chimpanzee and in early hominids.</p>
},
	keywords = {Chimpanzees},
	issn = {0047-2484},
	doi = {http://dx.doi.org/10.1016/S0047-2484(84)80055-X},
	url = {http://www.sciencedirect.com/science/article/pii/S004724848480055X},
	author = {Christophe Boesch and Hedwige Boesch}
}
