In Carmen Cusack's Animals, Deviance, and Sex, Cusack writes about how male cichlid fish must blow sperm into a female's mouth (where she will be holding her eggs in her mouth) in order to reproduce.
Snowballing is a human thing, but certain animals also engage in a similar snowballing-like act. In the Handbook of Psychology and Sexual Orientation, researchers found when studying gay men that: 'Semen can carry symbolic meaning (and thus symbolic power) for some men, representing (1) successful completion of sexual behavior, and (2) sexual power, virility, strength, and masculinity.)' The New Partridge Dictionary of American Slang notes that the term is of US origin dating back to 1972, and was first used exclusively by gay men. The podcast host and sex columnist Dan Savage, referred to the mixture of fluids as 'pud' in a column from 1999.