When Faced With Competition, Duck Penises Get Weird(er)

By Nathaniel Scharping | September 20, 2017 12:48 pm
Is he one of the lucky ones? (Credit: Shutterstock/Herman Veenendaal

Is he one of the lucky ones? (Credit: Shutterstock/Herman Veenendaal

Dating is a tough game. No matter where you go, it seems like there’s always someone who’s more attractive, funnier or remembers to shower. Losing out sucks, but hey, at least you get to keep your penis.

Not so for ruddy ducks. They only grow penises during mating season, and when forced to compete for mates, the scrawnier ducks don’t even bother to put in much effort. Some ruddy ducks can grow penises that measure up to seven inches in length, but the weaker among them seem to put off sexual maturity, sprouting just a nub when mating season comes around and opting to save their energy for more important tasks.

Penis Envy

Researchers from Mount Holyoke College conducted a study of ruddy ducks and another species, the lesser squap. They put male ducks of each species in one of two situations during mating season: They were either penned alone with a female, or in a more intense environment with many competing males. The results were published in The Auk: Ornithological Advances.

In both species, the more dominant ducks grew larger penises, but the difference was much more pronounced among the ruddy ducks. While the “lesser” lesser scaups grew smaller penises, in the first year of the experiment, the smaller ruddy ducks grew next to nothing at all. The next year, they seem to have gotten a confidence boost: the ducks grew penises, but they still disappeared much more quickly than normal. The first year of the experiment involved ducks that were just on the cusp of reaching sexual maturity, and it seems that those who felt at a disadvantage chose to put off mating for another year.

Not This Year

The variable nature of genital growth in the ducks seems to come down to social factors. In ruddy ducks especially, mating is a competitive game. Come breeding season, males sport colorful chestnut plumage and bright blue beaks, and engage in elaborate courtship displays. In addition, they can be extremely aggressive toward each other when fighting for mates. The energy expenditure and risk of injury might not be worth it for smaller ducks. This could also explain why smaller ducks kept their penises less than half as long as larger ducks — in ruddy duck society, having a penis makes you a target.

This is just one of the ways the sexual arms race plays out among ducks. Other species are famous for having oddly long, corkscrewing penises that grow explosively (not for the faint of heart) when it’s time to mate. The convoluted growth is an adaptation to the labyrinthian female duck vagina, which can contain dead ends, allowing them to better choose who they want to mate with.

Indeed, at up to seven inches ruddy duck penises are sometimes longer than their bodies. “I can’t imagine they could grow any longer,” says study lead author Patricia Brennan, speaking to Nature.

CATEGORIZED UNDER: Living World, top posts
  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    Social intent would limit breeding to the least robust and capable ducks in compensation. The most qualified drakes would be eliminated to end male patriarchal hegemony. DOI:10.1080/23311886.2017.1330439

    “The conceptual penis presents significant problems for gender identity and reproductive identity within social and family dynamics, is exclusionary to disenfranchised communities based upon gender or reproductive identity, is an enduring source of abuse for women and other gender-marginalized groups and individuals, is the universal performative source of rape, and is the conceptual driver behind much of climate change.”

    A duck egg over easy in bacon grease is absolute joy. That is what second on the food chain obtains for any organism. Think of it as evolution in action.

    • I’m me

      The ultimate trick is to get them to castrate themselves. It’s working wonderfully in America.

    • mlang

      It sounds like you’ve had an extremely bad life and I feel sorry for you. I find none of your comments relative.

      • mlang

        other than the duck egg over easy

      • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

        “I vas ein gaucho in den Argentina pampas während ze Clinton campaign!”

    • mlang

      Uncle Al,
      Nin de yi si she nin xiang Clinton bu xing ma?

      • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

        “I vas ein gaucho in den Argentina pampas während ze Clinton campaign!”

        Youtube v=t3zkB3fGPa8 Educating the electorate, furthering the daily struggle, ending counterrevolutionary dissent. DUCK!

  • baron von chilidog

    I am impressed that no one has yet wanted to rename a variety of this particular fowl the Trump. Allow me the honor. If ever there was a vertebrate that would go for a new tool annually, well……

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      The hive mind does not buzz, it quacks.

      It’s a duck with a blue bill. Aren’t you the least bit interested in how blue is generated re a huge reward for blue roses?

  • AlgorithmicAnalyst

    Did they measure testosterone levels?

  • anonymous….

    duck penis the f***


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