Three North African paleolithic bifacial Handaxes of Homo heidelbergensis / early H. sapiens dating from between 400, 000 to 100, 000 years ago. All three show the conservative perfected teardrop shape that typifies many handaxes of the mid to late paleolithic period. The largest handaxe measures nearly thirty centimeters, the smallest less than ten. The smallest handaxe is in green jasper, the middle a coarse-grained quartz arenite sandstone and the largest in volcanic rhyolite. The clear effort that went into the symetry of the middle axe appears to go beyond the purely utilitarian - and some have argued that perfect handaxes may have been a way of advertising skill or intelligence, and hence vehicles for human sexual selection. The majority of handaxes found tend to be of cruder form, and they have been demonstrated to be highly effective butchery tools.