New research has revealed that male desert darkling beetles engage in oral sex with females to obtain consent to mate.
Scientists at Chinese Academy of Agricultural Science observed precopulatory oral sexual for the first time among the cryptic desert beetle Platyope mongolica (P. mongolica), an act in which the males contact the female’s genitals using their mouths.
The team, who conducted the study in Mongolia, China, identified four steps of the insect’s natural mating process: males pursuing females, oral sexual contact, mounting, and copulation.
However, if a female is not satisfied with the male’s performance, it will runaway and leave the male beetle to continue searching for a mate to mount and copulate.
New research has revealed that male desert darkling beetles engage in oral sexual contact with females in an attempt to win their consent. A new study also revealed that the less time a male has with his females, the greater the chance of him failing to have sex.
Researchers collected male and female beetles from the field, then observed them in a laboratory setting.
They were able to observe the precopulatory oral sexual process closely. Males used their maxillary Palpi (a sensor organ in the mouth) to touch the female’s genitals.
Researchers observed that females attracted males when they displayed their abdomens upwards to indicate an interest in sexual activity.
‘Females usually stop moving and prostrate their heads as they extend their abdominal terminus higher to submit to mating,’ reads the study published in Ecology and Evolution.
However, if a female is not satisfied with the male’s performance, it will runaway and leave the male beetle to continue searching for a mate to mount and copulate
‘Males search and pursue females until the females stop moving. The remarkable courtship before copulation is that males repeatedly rub their maxillary palpi on the female’s genitals before an attempt to copulate.’
To better understand the role of oral sex in successful copulation, four experiments were performed.
The male antennae of the males were taken out in one experiment. However, the female antennae were kept intact. In the second experiment researchers only removed the maxillary palesi. Females remained unchanged.
During the third experiment, the female’s genitals was coated with petroleum jelly and in the last portion of the study, the males and females were left intact and undisturbed.
‘Results showed that copulation duration significantly decreased after removal of males’ maxillary palpi,’ researchers wrote in the study.
‘Removal of males’ antennae did not decrease copulation duration with females.’
‘However, all the interference treatments (T1-T3) have a significant decrease in the rate of successful copulation.’
The study also showed that the male’s time spent on sexual contact is shorter than the male’s time on trying to get pregnant.
‘We confirm that precopulatory oral sexual contact is a form of investment for successful copulation,’ the study reads.
‘Our study adds to a new understanding of the evolutionary significance of precopulatory oral sexual behavior in insects, making substantial contributions to sexual selection and evolution.’