# Why did humans choose to domestic only the birds with penises? **URL:** \ **Category:** Factual Questions\ **Created:** [December 31, 2019, 9:37pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692 "2019-12-31T21:37:10Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [December 31, 2019, 9:37pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/1 "2019-12-31T21:37:10Z")
In the course of a discussion on Twitter regarding what makes a good (more usually a bad) sex scene, someone mentioned that people should try reading a book of comparative reproductive systems, and that even amongst mammals things got a bit strange. To which someone else responded, “One word: ducks”. This got me curious, so I looked up duck reproductive systems and found a university site that gave a brief overview of duck reproductive organs and included the following gem of information: > [@](#): > > The phallus is the single intermittent organ of the Duck, and is similar to the penis of other taxa and the hemipenes of the Copperhead snake. The phallus is known as the “true penis,” and is only found in the domestic birds such as the duck, chicken, turkey, and geese. It is not present in the many other birds. So now I’m wondering, what could have prompted the domesticating humans to say: Bird with penis: let’s domesticate that sucker! Bird without penis: naw, we don’t want that in our farmyard. Yes, I know that not all species of duck, goose, or turkey are domesticated, but when you look at farm fowl, you see almost exclusively duck, goose, turkey, and chicken. (Secondary question: is there such a thing as wild (not feral, wild) chickens?) And I know that other bird species such as quail and pheasant and emu are now farmed, but I think that’s a comparatively recent development. Link to university site. Spoiler tagged because it shows photographs of duck reproductive organs as well as duck innards, and some people may find that gross. (I sure did. I did \*not \*expect to be looking at a dissection or surgery or whatever that was. Ugh.) [Duck reproductive organ information](https://campus.murraystate.edu/faculty/tderting/cva_atlases/canduck/reproduck.htm) ---
**Author:** ![vonespy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/vonespy/32/6204_2.png) [@vonespy](https://boards.straightdope.com/u/vonespy)\ **Post date:** [December 31, 2019, 9:47pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/2 "2019-12-31T21:47:13Z")
I suspect this is correlation ≠ causation. This doesn’t sound like something that would be a conscious choice on the part of those domesticating animals. ---
**Author:** ![Kimera757](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kimera757/32/3765_2.png) [@Kimera757](https://boards.straightdope.com/u/Kimera757)\ **Post date:** [December 31, 2019, 9:51pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/3 "2019-12-31T21:51:41Z")
Humans domesticated (for food) any bird that is large enough (which means it has to grow fast) that can reproduce in captivity and doesn’t have other marks (such as being vicious, like many large flightless birds). I doubt the phallus has much of an impact on their mating behavior, so no impact on their ability to mate in captivity. Humans did domesticate other birds, but many of them were not domesticated for food (parrots, songbirds, etc). People did raise pigeons (in dovecotes) for food, and I think at one time people regularly ate starlings, neither of which have such external genitalia on their males. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [December 31, 2019, 9:59pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/4 "2019-12-31T21:59:27Z")
> [@Morgyn](#): > > (Secondary question: is there such a thing as wild (not feral, wild) chickens?) The red junglefowl is widespread in India, southeast Asia and Indonesia. The domestic chicken is a domesticated subspecies of the junglefowl. > **[Red junglefowl](https://en.wikipedia.org/wiki/Red_junglefowl)** > > Phasianus gallus Linnaeus, 1758 > The red junglefowl (Gallus gallus) is a tropical bird in the family Phasianidae. It ranges across much of Southeast Asia and parts of South Asia. It was formerly known as the bankiva or bankiva fowl. It is the species that gave rise to the chicken (Gallus domesticus); the grey junglefowl, Sri Lankan junglefowl and green junglefowl have also contributed genetic material to the gene pool of the chicken. > Evidence from the molecular level derived from whole-genome... ---
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [December 31, 2019, 10:13pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/5 "2019-12-31T22:13:18Z")
Yeah, I didn’t think that the penis played any part in choosing which birds to domesticate, it just seems weird that the ones picked to be domesticated for food animals were the only ones that had penises. ETA: junglefowl! COOL! Thanks, **markn+**. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 31, 2019, 10:13pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/6 "2019-12-31T22:13:18Z")
I suspect that all of the species you mention are related to each other, and because they’re related, they share a number of features in common. One of those features happens to be their genitalia, but other features were doubtless the reason for their domestication. ---
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [December 31, 2019, 10:24pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/7 "2019-12-31T22:24:23Z")
And I just learned that the university website is wrong in one respect: roosters do not have penises. I am verklempt. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [December 31, 2019, 10:31pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/8 "2019-12-31T22:31:10Z")
How do you think the rooster felt? ---
**Author:** ![lingyi](https://avatars.discourse-cdn.com/v4/letter/l/d2c977/32.png) [@lingyi](https://boards.straightdope.com/u/lingyi)\ **Post date:** [December 31, 2019, 10:39pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/9 "2019-12-31T22:39:19Z")
Just gotta say what everybody’s thinking…so why are they called cocks?! 😃 ---
**Author:** ![JKellyMap](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jkellymap/32/15880_2.png) [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)\ **Post date:** [December 31, 2019, 10:49pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/10 "2019-12-31T22:49:35Z")
> **[Private Parts](https://slate.com/podcasts/lexicon-valley/2019/12/taboo-words-for-human-genitalia)** > > A history and etymology of vulgar terms for human genitalia. 40-minute fun podcast with linguist John McWhorter on “What does a rooster have to do with male genitalia anyway?” and related matters. ---
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [December 31, 2019, 11:17pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/11 "2019-12-31T23:17:31Z")
And it turns out the university didn’t lie. [Roosters do have penises](https://www.nationalgeographic.com/science/phenomena/2013/06/06/how-chickens-lost-their-penises-ducks-kept-theirs/), but they’re non-penetrative and have nothing to do with reproduction. I did not expect to end my year looking up the various reproductive capabilities of fowls. What a weird world. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 31, 2019, 11:31pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/12 "2019-12-31T23:31:35Z")
If they have an organ that’s non-penetrative and non-reproductive, why does it get called a penis? ---
**Author:** ![Morgyn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/morgyn/32/3041_2.png) [@Morgyn](https://boards.straightdope.com/u/Morgyn)\ **Post date:** [December 31, 2019, 11:35pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/13 "2019-12-31T23:35:15Z")
> [@Chronos](#): > > If they have an organ that’s non-penetrative and non-reproductive, why does it get called a penis? I have no idea. But apparently, it is. Maybe \*\*Colibri \*\*would know? ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [January 1, 2020, 12:00am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/14 "2020-01-01T00:00:49Z")
> [@Morgyn](#): > > And I know that other bird species such as quail and pheasant and emu are now farmed, but I think that’s a comparatively recent development. It’s not recent for most of those. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [January 1, 2020, 12:38am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/15 "2020-01-01T00:38:20Z")
I’ve seen junglefowl in Hawai’i. They’re pretty impressive birds. Not nearly as goofy and harmless-looking as their barnyard cousins. ---
**Author:** ![RioRico](https://avatars.discourse-cdn.com/v4/letter/r/f04885/32.png) [@RioRico](https://boards.straightdope.com/u/RioRico)\ **Post date:** [January 1, 2020, 12:51am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/16 "2020-01-01T00:51:31Z")
DIRTY DUCK was an X-rated comic creation of Bobby London. He earned the name. Not very domesticated, no. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [January 1, 2020, 1:25am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/17 "2020-01-01T01:25:47Z")
> [@Chronos](#): > > If they have an organ that’s non-penetrative and non-reproductive, why does it get called a penis? Because “appendix” was already taken? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [January 1, 2020, 1:32am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/18 "2020-01-01T01:32:08Z")
> [@Chronos](#): > > If they have an organ that’s non-penetrative and non-reproductive, why does it get called a penis? > [@Morgyn](#): > > I have no idea. But apparently, it is. Maybe \*\*Colibri \*\*would know? They seem to be calling it a penis to make a point. It’s just a vestigial homolog of a true penis. It’s like saying that humans have a tail because we possess a coccyx. I wouldn’t refer to it as a penis myself. As mentioned above, functional penises are found in ducks and geese but not chickens or turkeys. Ducks have dicks, but cocks are cockless. As mentioned, the groups of birds that have penises are: Ratites, including ostriches, rheas, emus, and cassowaries (but not kiwis) Guans and curassows, a family of chicken-like birds that appear to have regained them after other members of their group lost them. Ducks and other waterfowls. Besides these, males of two species of [Buffalo Weavers](https://www.nature.com/articles/19884) possess a pseudo-penis or phalloid organ which is not erectile and does not transmit sperm, but apparently is used in sexual stimulation. ---
**Author:** ![lingyi](https://avatars.discourse-cdn.com/v4/letter/l/d2c977/32.png) [@lingyi](https://boards.straightdope.com/u/lingyi)\ **Post date:** [January 1, 2020, 1:33am UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/19 "2020-01-01T01:33:50Z")
> [@Chronos](#): > > If they have an organ that’s non-penetrative and non-reproductive, why does it get called a penis? My penis is non-pe…umm nevermind…😃 ---
**Author:** ![Horatio\_Hellpop](https://avatars.discourse-cdn.com/v4/letter/h/e5b9ba/32.png) [@Horatio\_Hellpop](https://boards.straightdope.com/u/Horatio_Hellpop)\ **Post date:** [January 1, 2020, 12:16pm UTC](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692/20 "2020-01-01T12:16:06Z")
Why aren’t pet birds–parrot, canary, cockatoo, pigeon, falcon–included in your definition of “domesticated”? I have no idea whether any of these have penises. If you just mean birds that are raised for humans to eat, it seems to me that a lot of other birds used to find their way to our tables, though they were hunted or trapped, not raised. Also, I wonder if “true penises” might not be a result of being farm-bred and -raised, not the reason for it? Farmed salmon have different characteristics than wild ones, though probably not that one. [Next page](https://boards.straightdope.com/t/why-did-humans-choose-to-domestic-only-the-birds-with-penises/845692.md?page=2)