Neck-biting boner lust, bisexuality and headless orgies are apparently pretty old news, judging from these ancient pornographic images that date back to nearly 4,000 years ago. We always knew Captain Caveman was secretly a freak.

Although this prehistoric whacking material was originally discovered in the late 80s by Chinese Archaeologist Wang Binghau, it was not until the Kangjiashimenji Petroglyphs recently fell into the hands of the experts from the Center for the Study of Eurasian Nomads that there was some clarity behind what our randy ancestors were trying to say.

According to Dr. Jeannine Davis-Kimball, an expert on Eurasian nomads, this discovery of nearly 100 figures, ranging in size from a few inches up to nine feet tall, details a ceremonial fertility ritual that makes the sexual deviance during the time of Caligula’s reign of sodomizing terror look relatively mild.

In one sex scene, a group of 10 females and 6 males -- one wearing a monkey mask -- are getting ready to start organ grinding, while another scene depicts a male with a grossly exaggerated penis looking to knock boots with a nearby female figure, while three others wait patiently in line to do the same. A closer look at the bottom of this image reveals a man wrestling the ol' bald headed champ and ejaculating out a steady flow of babies – likely representing his ability to successfully procreate. Very literal; we appreciate the frankness.

Interestingly, Dr. Davis-Kimball says that all of these images appear to be some type of storyboard carved out by cultic leaders to illustrate the sexual hierarchy in their community. However, there is a chance that these images could simply be evidence of the first prehistoric porno magazine - let's call it Love on the Rocks.

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