Analysis of information sources in references of the Wikipedia article "Grotta dell'Addaura" in English language version.
They encircle two other bird-masked men, both with erect penises. Parallel lines connect the neck to the buttocks and ankles and the penis of one man to the buttocks of another. Thought by most scholars to be a sacrificial rite in which the parallel lines represent bindings, other interpreters see this as a homoerotic initiatory rite, with the lines possibly representing male energy, or even ejaculation.