The disturbing story behind duck mating will shock you, says Harvard professor

You may not have thought much about sex with ducks, but it turns out the birds have an annoying mating method.

Professor of Zoology at Harvard University, Richard O. Broome, an avian studies specialist, has written a book about the unthinkable act — with details more shocking than you might think.

Just like their human counterparts, males need certain attractive characteristics in order to seduce females.

For ducks and other birds, this means a lot of attention is focused on her or her feathers — but not everyone has a display worth showing off.

This means that FForced copulation is “widely common in many duck species,” according to the award-winning academic.

When ducks mate, their male organs grow back. Each mating season, the penis begins to shrink until it reaches 10% of its full size. In the photo, a male goosander duck is swimming in the river. Pictured here is a male rufous duck with its distinctive blue beak

How females evolved into the dark side of duck mating

He even described them as socially organized “mass rapes” that are “violent, ugly and even deadly”, in his 2017 book.

“Male ducks have evolved penises that enable them to force their way into the vagina of an unwilling female,” he wrote.

The academic claimed that this represented “a selfish male evolutionary strategy that conflicts with the evolutionary interests of its female victims and perhaps with the evolutionary interests of the entire species.”

Fortunately, female ducks can defend themselves using their complex anatomy: their vaginas are spiral-shaped, making them difficult to penetrate.

Professor Broome explained: “Females have evolved a new way – an anatomical mechanism – to counteract the explosive erectile action of male ducks and prevent the males from forcibly fertilizing their eggs.”

This type of sexual evolution is called antagonistic coevolution – reproductive organs have evolved to keep up with threats.

Male ducks are famous for their bizarre penises (pictured are male rufous ducks), which are spiral-shaped, exceptionally long and expand explosively when it’s time to mate.

How ducks actually mate

He also explained that, unlike 97% of birds, ducks have a penis, and boast being among the most endowed vertebrates, if you measure the body-to-organ ratio.

When ducks mate, their male organs grow back. Each mating season, the penis begins to shrink until it reaches 10% of its full size.

It returns to its usual size when the season ends and is stored inside the body, only coming out to mate.

Broome described the process as “like a cross between using your arm backwards.” Jacket sleeve inside out and the motorized soft top of a convertible sports car opens with a hydraulic drive.

However, this is not the only strangeness found in the duck mating process. The actual penis itself Spirals counterclockwise from base to tip.

In his book, The Evolution of Beauty: How Darwin’s Forgotten Theory of Mate Choice Shapes the Animal World — and Us, Broome writes:Like a selection of sex toys from a vending machine at a weird tavern, duck penises come in ribbed, contoured, and even serrated varieties.

This is “to attach to the female reproductive system,” he explained, which is long and twisted like a penis.

And it doesn’t stop there – the female duck’s reproductive organs are also strange – they are full “Blocked side pockets or dead ends,” according to the professor.

Unlike their male counterparts, some of them spiral clockwise, and in the opposite direction of the counterclockwise spiraling duck penis.