From LiveScience:
Male bats perform oral sex on females, apparently to make sex last longer, researchers say.
These findings, the first discovery of male-to-female oral sex in bats, match prior studies revealing that female bats perform fellatio, or oral sex, on male bats.
Scientists analyzed a colony of about 420 Indian flying foxes (Pteropus giganteus) roosting in a single fig tree in southern India, near the village of Nallachampatti. This fruit-eating bat is one of the largest bats in the world.
Over the course of more than 13 months, using binoculars and a video camera, researchers witnessed 57 cases of sex ― oral and intercourse ― usually in the morning.
"Apart from humans, bats also exhibit oral sex as a courtship behavior," said Ganapathy Marimuthu, a bat researcher at Madurai Kamaraj University in India.
Initially, males groomed their penises to go erect before approaching females. When they gently touched females with their wings, females typically moved away, and males followed. [See Video of Bats Having Oral Sex]
When the females stopped moving, the males started licking the females’ vaginas ― the act known as cunnilingus. This foreplay may help arouse and lubricate females, the researchers said.
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