Are Ducks Proof That Size Matters?
For some ducks, size matters, and science can prove it!
(serious geek alert)
This is a story about duck dicks and how they may prove that size matters.
At least they prove it for some species, not so much for others. It’s for science geeks, people with great sexual curiosity, and those who love us.
OK, so I’m not an evolutionary biologist. If there’s one way I’ve been blessed, it’s a natural aptitude for science. It’s just a subject that comes easily to me. I understand and retain what I read without much effort.
My highest score on the ACT college placement exam was Natural Science, a perfect 34. Social Science was a close second at 33. In fact, my overall ACT scores were high enough I was able to use them for entry into MENSA.
So, being a science geek, finding an article on the “phenotypic plasticity of penis morphology” – how could I possibly resist blogging?
For some ducks dick size matters!
This is an excellent experimental study of penis morphology, looking at the effects of social environment on penis size in two duck species that have different mating systems.Bob Montgomerie
The question of penis size is one that scientists have studied in a great number of species. For instance, I remember reading that promiscuous monkey species tend to have larger genitals (especially testes) when compared with their monogamous cousins. That this particular trait is also found to be true in ducks comes as no great surprise.
Differences in the age of sexual maturation among ducks raised in populations segregated by sex also come as no surprise. Evolution has designed a myriad number of mechanisms for survival of the species. To a great extent, it flies in the face of scientists who say testosterone is irrelevant (ie – Science Book of the Year award winner Testosterone Rex). At least that’s my opinion as a science layman.
But, learning that the males of some duck species grow larger sex organs when segregated among other males is real news. That could have implications for our understanding of both reproductive and evolutionary mating strategies.
<h4>does size matter? – it’s complicated!</h4>
Male ducks have some of the weirdest junk in nature—a ludicrously long, corkscrew-shaped member that evolved on account of an ongoing battle of the sexes. New research shows that the social environment in which the male duck finds himself in has a pronounced effect on the length of his penis, a finding that may finally put the “size matters” debate to rest. For ducks.
When it comes to sex, male and female ducks are locked in an intense sexual conflict that has led to some seriously weird genitals on both sides. Typically, female ducks pair off with a preferred mate during the breeding season, but they also get harassed by guys who don’t take the hint. Scientists estimate that a third of all duck matings are forced, leading to a genital arms race in which the twisted configuration of the female reproductive tracts, or oviducts, restore female choice. While the male’s corkscrew-shaped penis twists in a clockwise fashion, the female oviduct twists in the opposite direction. The result is that the majority of forced copulations don’t lead to fertilization.
Given the extent of this genital arms race, Patricia Brennan, an ornithologist at Mount Holyoke College, hypothesized that intense male-on-male competition may affect the development and shape of a penis over the course of a male duck’s lifetime. And so she conducted an experiment, the results of which now appear in The Auk: Ornithological Advances.
Brennan’s experiment involved two species, the very promiscuous Ruddy Duck and the pair-bonding Lesser Scaup. As would be expected, Ruddy Ducks have long members, whereas Lesser Scaups, as their name unintentionally suggests, do not. The researchers studied captive ducks of both species across two breeding seasons at the Livingston Ripley Waterfowl Conservancy in Litchfield, Connecticut, USA.
During the mating season, male ducks were either kept together with other males (the experimental group) or with a single female (the control group, lucky them). When measuring the male penises afterwards, the researchers found that the Lesser Scaup featured longer penises on average when housed with other males. This implies that Brennan’s hypothesis of “phenotypic plasticity of penis morphology” was correct, but things were a bit more complicated for the Ruddy Duck.George Dvorsky
Why does duck dick size matter?
Forced sex is at the crux of this evolutionary matter. Apparently, the reason size matters for ducks is because rape is a common mating strategy among some species. It’s a behavior I’ve observed first hand.
Back when I was 17, I spent a lot of my study time at a municipal park with a serene pond that attracted a good number of mallards. During breaks from schoolwork, I observed a great number of sexual assaults by aggressive groups of male ducks.
They were cooperating together in what could only be described as rape gangs. Most of these duck rapes consisted of a pair of males assaulting a lone female. Frequently, however, I witnessed three or four males taking turns with a single female duck.
Those kinds of behaviors lead to unique evolutionary pressures within mating strategies. There’s not much point in “pulling a train” on a female duck if you have only a one in three chance of being the eventual father of her offspring. It’s said that this sexually predatory nature leads to an evolutionary arms race among males.
size matters in arms races
In a real-life arms race, the end result is often the battlefield evolution of bigger and bigger guns. The British started World War II sporting the 2-pounder anti-tank gun. Six years later, at war’s end, they used the 17-pounder. Bigger guns were on the drawing board.
Now, it can be said, the same is true for ducks. Some duck species are in an evolutionary arms race leading to bigger “guns” under certain conditions.
This is a rare moment of serendipity where my interest in weird sexual science intersects with my aptitude for both the social and natural sciences. Not to mention the fact that it gives a whole new meaning to being a “grower”.
Penile plasticity is not a phenomenon that occurs in humans. Thankfully, we mate differently than ducks. But, imagine for a moment that it did happen. Under those conditions, males raised with other males would tend to have larger cocks.
I’m guessing that would be a great boon for the growth of all-male boarding schools. And, it would also give all new meaning to the old phrase, “Don’t be a fool, stay in school…”