In fact, as with modern females and hominoid females, it is likely that hominid females, including even the Cro-Magnon, regularly engaged in bisexual relations. This bisexual female tendency may explain why phallic objects little different from the double-dildos that grace modern sex shops, were being fashioned and employed, presumably by female hands, during the Upper Paleolithic.

For example, the Gorge d`Enfer double dildo fashioned during the Upper Paleolithic is obviously designed to be used by two women while having "intercourse" with one another. Likewise, female primates have also been observed to masturbate by ing sticks and other objects into their vaginas, and/or by sticking their hands, fingers, and tongues into the vaginas of other estrus females.

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