And now for something completely salacious

[ILLigitt]

And now for something completely salacious

I forgot to proffer this paper of the week before I left. The title alone is a classic: Fellatio by fruit bats prolongs copulation time. 2009. M. Tan, G. Jones, G. Zhu, J. Ye, T. Hong, S. Zhou, S. Zhang, and L. Zhang. PLoS One :4(10): e7595. doi:10.1371/journal.pone.0007595. Be sure to check out the short video at the end of the paper.

You can imagine snickering that went along with writing this abstract:

Oral sex is widely used in human foreplay, but rarely documented in other animals. Fellatio has been recorded in bonobos Pan paniscus, but even then functions largely as play behaviour among juvenile males. The short-nosed fruit bat Cynopterus sphinx exhibits resource defence polygyny and one sexually active male often roosts with groups of females in tents made from leaves. Female bats often lick their mate’s ***** during dorsoventral copulation. The female lowers her head to lick the shaft or the base of the male’s ***** but does not lick the glans ***** which has already penetrated the ******. Males never withdrew their ***** when it was licked by the mating partner. A positive relationship exists between the length of time that the female licked the male’s ***** during copulation and the duration of copulation. Furthermore, mating pairs spent significantly more time in copulation if the female licked her mate’s ***** than if fellatio was absent. Males also show postcopulatory genital grooming after intromission. At present, we do not know why genital licking occurs, and we present four non-mutually exclusive hypotheses that may explain the function of fellatio in C. sphinx.

Seriously, why the licking? Here are the authors’ four theories:

First, genital licking may lubricate the ***** or increase penile stimulation, prolonging the duration of copulation. Prolonged copulation might assist sperm transport from the ****** to the oviduct, or stimulate secretions of the pituitary gland in the female [26] and hence increase the likelihood of fertilization. Second, prolonged copulation might be a method of mate-guarding, because the mates would normally segregate after copulation to form unisexual groups which persist throughout the non-breeding season [29]. Third, fellatio may confer bactericidal benefits and assist in the prevention of sexually transmitted diseases (STDs) both to females [30]–[33], and to males that lick their own ***** briefly after copulation [34]–[37]. Saliva has a protective repertoire that goes beyond antibacterial activity to include antifungal, antichlamydial, and antiviral properties as well [38]. Finally, genital licking may facilitate the detection and identification of MHC-dependent chemical cues associated with mate choice [39], [40].

Reposted from Why Evolution Is True