# For The Curious: Gene Mapping Shows What the Platypus Is Made Of **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [December 29, 2009, 5:15pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927 "2009-12-29T17:15:27Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Least\_Original\_User\_Name\_Ever](https://avatars.discourse-cdn.com/v4/letter/l/e480ec/32.png) [@Least\_Original\_User\_Name\_Ever](https://boards.straightdope.com/u/Least_Original_User_Name_Ever)\ **Post date:** [December 29, 2009, 5:15pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/1 "2009-12-29T17:15:27Z")
[Here](http://www.usatoday.com/tech/science/genetics/2008-05-08-platypus-genetic-map_N.htm). Well, the joke did always talk about the platypus being a mix of three creatures, and it appears that it’s correct on a genetic level. ---
**Author:** ![Ellen\_Cherry](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ellen_cherry/32/3600_2.png) [@Ellen\_Cherry](https://boards.straightdope.com/u/Ellen_Cherry)\ **Post date:** [December 29, 2009, 6:07pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/2 "2009-12-29T18:07:55Z")
And part secret agent! 😛 ---
**Author:** ![Mr.Moto](https://avatars.discourse-cdn.com/v4/letter/m/9de0a6/32.png) [@Mr.Moto](https://boards.straightdope.com/u/Mr.Moto)\ **Post date:** [December 29, 2009, 6:45pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/3 "2009-12-29T18:45:38Z")
Someone has kids in the house. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [December 29, 2009, 7:05pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/4 "2009-12-29T19:05:01Z")
Perry! ---
**Author:** ![Angel\_of\_Doubt](https://avatars.discourse-cdn.com/v4/letter/a/7cd45c/32.png) [@Angel\_of\_Doubt](https://boards.straightdope.com/u/Angel_of_Doubt)\ **Post date:** [December 29, 2009, 7:05pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/5 "2009-12-29T19:05:58Z")
No kids in this house, and I know ALL ABOUT the secret agent part! ---
**Author:** ![TruCelt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/trucelt/32/523_2.png) [@TruCelt](https://boards.straightdope.com/u/TruCelt)\ **Post date:** [December 29, 2009, 7:17pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/6 "2009-12-29T19:17:13Z")
I had no idea about the venom. Very interesting. I wonder if this is the only animal which uses venom in a mating strategy? I’ve only ever heard of it as a primary feeding strategy for killing/stunning and as a secondary purpose of self-defense. > [@](#): > > . . . Graves said the research contained some surprises, such as the conclusion that genes which determine sex in a platypus are similar to those of a bird, not a mammal. I don’t understand why this would be surprising. They have a bill, and lay eggs, of course they have a bird-like reproductive system. That would have been my first guess. ---
**Author:** ![Mr.Moto](https://avatars.discourse-cdn.com/v4/letter/m/9de0a6/32.png) [@Mr.Moto](https://boards.straightdope.com/u/Mr.Moto)\ **Post date:** [December 29, 2009, 7:58pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/7 "2009-12-29T19:58:57Z")
> [@Angel\_of\_Doubt](#): > > No kids in this house, and I know ALL ABOUT the secret agent part! Why yes, yes you do. ---
**Author:** ![armedmonkey](https://avatars.discourse-cdn.com/v4/letter/a/d6d6ee/32.png) [@armedmonkey](https://boards.straightdope.com/u/armedmonkey)\ **Post date:** [December 29, 2009, 7:59pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/8 "2009-12-29T19:59:41Z")
Part mammal, part bird, and part reptile. How did that happen? "Dear _Penthouse_, I never thought this would happen to me, but a crocodile with a duck on her back walked into my bar and… ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [December 29, 2009, 8:04pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/9 "2009-12-29T20:04:40Z")
So… umm… can you milk a platypus? ---
**Author:** ![E-Sabbath](https://avatars.discourse-cdn.com/v4/letter/e/e19adc/32.png) [@E-Sabbath](https://boards.straightdope.com/u/E-Sabbath)\ **Post date:** [December 29, 2009, 8:15pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/10 "2009-12-29T20:15:49Z")
Sort of. It oozes from the chest. ---
**Author:** ![Malleus\_Incus\_Stapes](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/malleus_incus_stapes/32/3293_2.png) [@Malleus\_Incus\_Stapes](https://boards.straightdope.com/u/Malleus_Incus_Stapes)\ **Post date:** [December 29, 2009, 8:26pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/11 "2009-12-29T20:26:59Z")
Right. She doesn’t have nipples per say, just holes or pores that the milk oozes out of. The babies lick, not suckle. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [December 29, 2009, 8:29pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/12 "2009-12-29T20:29:37Z")
_HORK_ ---
**Author:** ![E-Sabbath](https://avatars.discourse-cdn.com/v4/letter/e/e19adc/32.png) [@E-Sabbath](https://boards.straightdope.com/u/E-Sabbath)\ **Post date:** [December 30, 2009, 12:34am UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/13 "2009-12-30T00:34:20Z")
The real question is why, exactly, I know how platypi lactate without looking it up. I mean, off the top of my head, I know this answer. There’s something horribly wrong with me. ---
**Author:** ![Oslo\_Ostragoth](https://avatars.discourse-cdn.com/v4/letter/o/a9a28c/32.png) [@Oslo\_Ostragoth](https://boards.straightdope.com/u/Oslo_Ostragoth)\ **Post date:** [December 30, 2009, 7:58am UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/14 "2009-12-30T07:58:19Z")
All I can say is, I want to know about this. Holy crap, what a strange animal! ---
**Author:** ![Antigen](https://avatars.discourse-cdn.com/v4/letter/a/848f3c/32.png) [@Antigen](https://boards.straightdope.com/u/Antigen)\ **Post date:** [December 30, 2009, 12:53pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/15 "2009-12-30T12:53:55Z")
> [@TruCelt](#): > > I had no idea about the venom. Very interesting. I wonder if this is the only animal which uses venom in a mating strategy? I’ve only ever heard of it as a primary feeding strategy for killing/stunning and as a secondary purpose of self-defense. Venom as a mating strategy? Did I miss something in the article? ---
**Author:** ![ShibbOleth](https://avatars.discourse-cdn.com/v4/letter/s/848f3c/32.png) [@ShibbOleth](https://boards.straightdope.com/u/ShibbOleth)\ **Post date:** [December 30, 2009, 1:11pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/16 "2009-12-30T13:11:46Z")
Hey, where’s Perry? As to venom involved in the mating strategy, I’ve known some people like that. ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [December 30, 2009, 3:20pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/17 "2009-12-30T15:20:35Z")
> [@TruCelt](#): > > I don’t understand why this would be surprising. They have a bill, and lay eggs, of course they have a bird-like reproductive system. That would have been my first guess. The platypus is no more closely related to birds than is any other mammal. They lay eggs as a holdover from a time when (almost) all amniotes laid eggs, not because they have a special relationship with birds. The bill and webbed feet are convergent evolution. Hence surprise when platypuses share other characteristics with birds. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [December 30, 2009, 3:26pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/18 "2009-12-30T15:26:03Z")
The article is vague, and I can’t be bothered to look up the actual information, but from what it said, my guess is that the platypus uses a ZW sex determination system, like birds, rather than an XY system, like mammals. In a ZW system, the male is XX and the female is XY - opposite of how we do it. That’s just a WAG, though, and anyone is welcome to prove me wrong. ---
**Author:** ![badbadrubberpiggy](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@badbadrubberpiggy](https://boards.straightdope.com/u/badbadrubberpiggy)\ **Post date:** [December 30, 2009, 4:58pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/19 "2009-12-30T16:58:31Z")
> [@E-Sabbath](#): > > The real question is why, exactly, I know how platypi lactate without looking it up. I mean, off the top of my head, I know this answer. > > There’s something horribly wrong with me. I knew about the milking part AND the venom. I sometimes worry that information like this takes up brain cells I could be using for things that are a little more relevant to my actual life. ---
**Author:** ![Malleus\_Incus\_Stapes](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/malleus_incus_stapes/32/3293_2.png) [@Malleus\_Incus\_Stapes](https://boards.straightdope.com/u/Malleus_Incus_Stapes)\ **Post date:** [December 30, 2009, 8:22pm UTC](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927/20 "2009-12-30T20:22:31Z")
> [@Smeghead](#): > > The article is vague, and I can’t be bothered to look up the actual information, but from what it said, my guess is that the platypus uses a ZW sex determination system, like birds, rather than an XY system, like mammals. In a ZW system, the male is XX and the female is XY - opposite of how we do it. That’s just a WAG, though, and anyone is welcome to prove me wrong. That was my understanding as well. **Antigen** - the males use their poison when they fight for females. I don’t know how potent it is to a fellow platypus. [Next page](https://boards.straightdope.com/t/for-the-curious-gene-mapping-shows-what-the-platypus-is-made-of/522927.md?page=2)