What's the deal with duckbill platypuses?

© David Watts/Visuals Unlimited/Corbis

It is pretty much impossible to describe duckbill platypuses without using the word "hodgepodge" and for good reason. These mammals also share features with birds, reptiles and even sharks. Learn about the these weird and peculiar (and surprisingly tiny) little creatures that both creationists and evolutionists claim as a demonstration of their beliefs.

Recording: Welcome to Stuff You Should Know from howstuffworks.com.

Chuck Bryant: Hey pal. Before we get going we would like to implore folks to go watch our little animated short series, four and five minute little animated shorts by Nick Shoen and they capture the essence of us like no one ever has.

Josh Clark: They are so good.

Chuck Bryant: They look really great.

Josh Clark: Animated bits from the audio podcast. So there'll be a sense of nostalgia for you as well.

Chuck Bryant: That's right. And people really love these but we want them to stick around which means we need more people to watch them so we don't ask for much but if you would go to stuffyoushouldknow.com and our Facebook page, we've got them there too and Josh is tweeting them out. Watch these little videos, share them with your friends. It's four minutes well spent.

Josh Clark: So go to stuffyoushouldknow.com, click on the video tab. They should be right there.

Chuck Bryant: Much appreciated.

Josh Clark: Thanks everybody. Hey welcome to the podcast. I'm Josh Clark and there's Charles W. (Chuck) Bryant and this is Stuff You Should Know.

Chuck Bryant: Zoological edition.

Josh Clark: I like these.

Chuck Bryant: I think we try to cover interesting animals. It's not that - all animals are interesting I think but we try to look up things like octopus and the platypus and other pusses.

Josh Clark: Butterflies is what you mean.

Chuck Bryant: And we did butterflies once with the [inaudible]. We've got to do that at some point too.

Josh Clark: Think a dolphin with a tusk.

Chuck Bryant: There you go. It'll be a short one.

Josh Clark: We just did the [inaudible]. We're talking today about the platypus. We've not ever done it before and despite Jerri's protests to the contrary we haven't recorded one. If we have Chuck and I have gone totally insane and have no recollection of it so if we did let us know.

Chuck Bryant: Well we covered weird animals in Australia or deadly animals in Australia, venomous animals in Australia but we have not covered the platypus.

Josh Clark: Have we mentioned the platypus in that because I don't recall knowing the platypus had venom.

Chuck Bryant: I don't think so. We definitely didn't.

Josh Clark: That's the big twist of this episode and I just ruined it for everybody. I'm sorry.

Chuck Bryant: There are so many twists with the platypus you can't - this is spoiler free.

Josh Clark: So did you much of the stuff beforehand?

Chuck Bryant: No. And in fact I did not know that they were so small.

Josh Clark: I didn't either. That took me by surprise. I thought they were maybe the size of my torso.

Chuck Bryant: I thought it was the size of a medium sized dog or something or a beaver and it kind of looks like a beaver that stuck its face in something and got it stuck. It looks like a beaver that stuck its face in a fake duckbill and can't get it off.

Josh Clark: It's not a very cute animal. I want it to be very cute and it's just not.

Chuck Bryant: But they are tiny. It's like the size of a very small cat even.

Josh Clark: They run about 5 pounds.

Chuck Bryant: A little more.

Josh Clark: Is that right? I saw 5 pounds somewhere.

Chuck Bryant: What's interesting is they're only found in eastern Australia up and down the coast down to island of Tasmania.

Josh Clark: Right and they love in wood lands and rivers.

Chuck Bryant: And the ones in the south though are larger.

Josh Clark: Is that right?

Chuck Bryant: Yeah. They can get up to 6 pounds. And the one in the north up in the Queensland coast, some of those are 2 1/2, 3 pounds. They're just teeny little cute guys.

Josh Clark: They're like tea cup platypuses.

Chuck Bryant: I've always seen pictures of them without a human around - a yuman. Did I say human?

Josh Clark: You did.

Chuck Bryant: Then when I saw - I watched a bunch of videos today. When I saw the people holding them up I was like, "That's just a little thing." So yes my answer the long one [inaudible]. I didn't know much about them.

Josh Clark: I didn't know much about them either. It turns out that most people don't because I've seen a lot of different stuff. Just that weight discrepancy is one example. Like we said, platypuses, they spend most of their lives long river banks and freshwater river banks we should say. Are there saltwater rivers? Sure there are.

Chuck Bryant: There's title creeks and stuff like that.

Josh Clark: These guys are freshwater animals and they hold their breath when they go eat food because they're actually bottom feeders but I saw a lot of different variations and estimates of how long they could hold their breath. Thirty seconds I saw all over the place. One person said eight minutes. I think one source said no, five I think is what one source said. I seen all over the place but the point is there's a lot of random fact floating around about platypuses and we're going to pile them all together here.

Chuck Bryant: That's right. I was instantly surprised by the fact that they were just on the east coast of Australia.

Josh Clark: I knew Australia.

Chuck Bryant: I didn't even know that.

Josh Clark: Really?

Chuck Bryant: No. For some reason I just didn't know that so apparently after Pangaea split it evolved on one of the huge chunks of land called Gondwana and that split, formed Australia and South America and some other places. And they were in South America and Australia at the time and then the ones in South America died off and all seas were just like [inaudible].

Josh Clark: What was that that happened just now?

Chuck Bryant: That was Australian. That was my best.

Josh Clark: The duckbill platypus as far as it's called today, that's obviously your opinion term for it. And it wasn't until almost the 19th century, 1798 that the platypus was first encountered by Europeans. Before that [inaudible] obviously had run into them before. They had names from Malingon, Bundaberg, Tenbrit.

Chuck Bryant: All better names.

Josh Clark: Than duckbill platypus. So the Aborigines knew about it and the first white colonists that showed up in Australia I guess heard legends of these things and then started to see them themselves. And even though these were Europeans telling other Europeans hey, there's a really weird animal down here. There are a bunch of weird animals. You're not going to believe the kangaroo but this thing had got all of them beat and people in Europe are like you're full of it. They sent them specimens, stuffed specimens and the taxidermists and the naturalists and biologists back in Europe said I still don't believe it because at the time - have you've ever seen the mermaid mummies?

Chuck Bryant: Yeah. The Chinese were into fabricating animals.

Josh Clark: So everybody thought it was a Chinese fake until somebody finally got their hands on one and dissected it. His name was Everard Jones and he proclaimed them real in 1802.

Chuck Bryant: It was funny for a while. They were like no, no. I think they called it the Indian Sea at the time. They were like [inaudible] close to China and you know they're just not so there with this stuff.

Josh Clark: It's real taxidermy.

Chuck Bryant: Pretty much. It's kind of cool that they were doing that though. I wonder if it was like a creative thing or - what were they doing?

Josh Clark: They were selling them to sailors.

Chuck Bryant: As some sort of scam?

Josh Clark: Yeah as a mermaid. They were like these are real mermaids from what I understand.

Chuck Bryant: Like the sea monkeys that you defend?

Josh Clark: But even less real.

Chuck Bryant Okay.

Josh Clark: So we finally established 1802 that platypuses are real and we start to just really dig in to figure out what is going on with these things. And the more we dig in the stranger things become so for example Chuck, platypus. It's a mammal and the reason it's a mammal is because it nurses its young and it has fur yet it doesn't have nipples. It secretes its milk through its abdomen like it's just leaking or something.

Chuck Bryant: Through pores and they're called puggles, their young are, and the puggles just suck on the abdomen and it's a very odd thing in nature for that to happen.

Josh Clark: It is peculiar.

Chuck Bryant: Very peculiar.

Josh Clark: Okay so they're mammals but they're not just mammals. They also straddle the line. Basically the platypus exists to strain the taxonomic system of classification of animals. They have that duck bill, that pesky duck bill.

Chuck Bryant: And the webbed feet. So they're birds right?

Josh Clark: I guess but I thought we just said they were mammals. I feel like I'm losing my mind.

Chuck Bryant: Officially they are mammals. That's not going to change although you never know. They do have the webbed feet and the duck bill and then they also have certain - they have eyes like a reptile. They lay eggs like a reptile, amphibians.

Josh Clark: They suckle their young through their abdomens with milk but they give birth to eggs so that's not supposed to happen either.

Chuck Bryant: No. The female, they have two ovaries. One of them functions, one of them doesn't and they lay these 1-3 little leathery eggs. They're a little more round than the oval bird eggs but they're eggs and they're born with teeth that fall out. Then they have these horny little plates that they mash their food up with.

Josh Clark: Yeah they don't have teeth.

Chuck Bryant: They're just weird. They're born with teeth.

Josh Clark: Right which actually I funny because both creationists and evolutionists hold the platypus up as evidence of their beliefs. The creationists are like if anything, it's reverse evolution. They lose their teeth and like you this thing was obviously a symbol. What evolves over hundreds of millions of years living by water but can only hold its breath for 30 seconds and eight minutes on who you ask say the creationists.

Evolutionists say this is probably the earliest example of a mammal to branch off from the mammalian line. So it fills in the gaps and our distant ancestry. It's a great example of evolution. The fact that is we still don't quite know what the deal is with this thing even after mapping its genome.

Chuck Bryant: I bet you there's a great political cartoon out there like a Christian pulling on the duck bill and the evolutionists pulling on the tail and the platypus in the middle like, "I just want to live." I guess I just wrote a political cartoon.

Josh Clark: Don't put your hang-ups on me.

Chuck Bryant: Exactly. All we need to do is be able to draw and we'd be set.

Josh Clark: So the strange parade of character traits - not character traits. That would be like whether it was good to its mother or something.

Chuck Bryant: Yeah.

Josh Clark: What is it called, phenotypes?

Chuck Bryant: It was biological traits I guess.

Josh Clark: That strange parade of those that has not ended yet. Platypuses are just one of two members of monotremes.

Chuck Bryant: Mammalian monotremes because birds are monotremes because they poop and hatch eggs out of the same hole.

Josh Clark: Call it colaka. But I guess as far as what you're saying, mammals are concerned. There's the spiny anteater and the platypus are the only ones who excrete and shoot eggs out of one hole.

Chuck Bryant: Is that what the akitna is, the spiny anteater?

Josh Clark: Yeah. It looks like a porcupine with a longer nose.

Chuck Bryant: They have one hole to do their business with and one hole to lay their eggs with.

Josh Clark: Which is also business.

Chuck Bryant: I guess you're right. And that is very much bird-like but like I said the eye structure is more reptilian so -

Josh Clark: You said the eggs were leathery. That's pretty reptilian.

Chuck Bryant: There's all over the map.

Josh Clark: It gets even stranger than that Chuck.

Chuck Bryant: Okay. What else we got?

Josh Clark: Let's dig a little deeper on that duck bill. There are tiny little pores. For a long time scientists were like how do we know that these things when they dive they're bottom feeders? They feed on shellfish, insects, things that live along of the muck of the bottom of the river. We know that they close their eyes and they close their nostrils when they dive. So how are they locating food? And they figured out there are tiny little holes on their duck bill that have electroreceptors in them just like a shark.

Chuck Bryant: I think we talked multiple times about the nose of a shark. That's why you punch the shark in the nose and that's how they feed. That will disrupt their brain if you give them a good sock in those electroreceptors and it's very similar. They sense movement through these receptors and they're blind to everything and this is how they find the shellfish and all that stuff.

Josh Clark: These receptors are so sensitive that even just the tiny movement of an insect's leg, the change in the electrical current in the water that that produces their electroreceptors pick up. That's how they go eat and they get a scoopful of food and they kind of pocket it in their cheek for a little while until they come back up. And then once they do use a bit of the grit of the river bottom to help with their teeth plates or whatever you call them to grind the food down.

Chuck Bryant: They're called horny plates.

Josh Clark: Their horny plates are aided with gravel and they chew. All right, we're starting to get kind of handle on this thing right?

Chuck Bryant: That's got to be the last weird thing right?

Josh Clark: It is not. We already mentioned it but they produce venom. They're one of only three types of mammals that produce venom. So think about this. You've got the akitna, the spiny ant eater. It's the only other monotremes but it doesn't have a duck bill. It doesn't lay eggs. It doesn't do all the other weird stuff. You've got a certain kind of shrew, surinedons.

They produce venom but they also don't have duck bills. They also don't have electroreceptors. Platypuses are the strangest hands down animal. Hodge-podge is the best way to describe them.

Chuck Bryant: They are hodge-podge and they straddle along these different classes and in the end I saw an interview with one lady who had worked on the genome project which we'll get to. And she was like when you're talking genetics like this weird is good. She's like this is awesome for us because it shows - I think she called it informal variation. So if you learn about all these weird things that a platypus has and its genetic code, it can help fill in because we're mammals too, some of the stuff we may not know about in ways that we are different and similar. It just helps inform everything basically all there with a little genome of the platypus.

Josh Clark: And actually not only the differences are good but also any similarities between us and them also shows this is a very ancient trait since they branched off of mammals 166 million years ago.

Chuck Bryant: You have a phony venomous stabber in your heel right now?

Josh Clark: Right. I try not to use it. Sometimes it's easier to just not use it than other times but yes I do.

Chuck Bryant: Plus they have venom. I think - isn't it just the males have that spur on the hind foot?

Josh Clark: Yeah and they mostly produce the venom during spring which is why they think it's probably used to fight other males. They live solitary.

Chuck Bryant: That would make sense because the females are born with one and it falls off so they wouldn't need one for that.

Josh Clark: Right and males will fight with one another for females, mate and then take off and then that's that. Everybody kind of lives on their own over a set amount of territory as a platypus but that venom doesn't kill other platypuses but it can kill a dog and it has before.

Chuck Bryant: And I'm surprised it doesn't kill another platypus. They have some resistance.

Josh Clark: That's what I think.

Chuck Bryant: It's got to be because they're smaller than most dogs.

Josh Clark: It hasn't ever killed a human but humans have been known to get stoned by these things and brother does it hurt. And the reason it hurts is because it is a mammalian venom and we have no known cure or treatment for the pain caused by that. So if you are stung by one of them you are totally on your own as far as pain management goes. There's nothing that can be done. You're just sitting there in agony for a week or two until it works itself out.

Chuck Bryant: I think it's supposed to suck pretty bad, swelling and lots of pain. Like you aid there's nothing that can be done. You just ride around and curse the platypus I guess and that's why you hold them by the tail too by the way. If you ever grab a platypus grab them by the tail because they don't mind it.

Josh Clark: Same with possums.

Chuck Bryant: Yeah but possums don't have a spur in the tail but they'll bite you.

Josh Clark: They will.

Chuck Bryant: They're mean. I don't know if that's true actually but they hiss.

Josh Clark: No they're real mean.

Chuck Bryant: Are they?

Josh Clark: They'll try to bite you. They'll try to curl up. If you hold the end of their tail they'll curl themselves up trying to get to your wrist which you really can't blame you. They're trying to get you to let them go but they'll bite you. They'll kill you and your whole family if you let them.

Chuck Bryant: I remember I was actually on one of my first dates with my high school girlfriend. We -

Josh Clark: Catching possums?

Chuck Bryant: It may have been my first date actually. I walked her back up to the front porch at the end of the night and it was that - it was like something on Norman Rockwell, all right can we get that first kiss? We walked up on the porch and it was - probably 4X4, it was small. There was a freaking possum up there that got stuck trying to get out and we were sharing this very small space with this possum hissing at us and screaming at us and it made for a very memorable end of the evening and I don't think I got the kiss.

Josh Clark: I thought you were going to say her dad came out to meet you and he turned out to be giant opossum.

Chuck Bryant: No, that didn't happen.

Josh Clark: What else? We were talking about the platypus genome project. You sound like you more about that than me.

Chuck Bryant: They did this - 100 scientists got together in 2008 and said if we can figure this thing out maybe we can help inform our own human species. And one thing they did find out is that we have two chromosomes. We have a pair. If you're a female you're going to be XX. If you're a male you're going to be XY. Birds have ZW for female and ZZ for male. Platypuses have - is it platypuses?

Josh Clark: Yeah.

Chuck Bryant: Okay. They have ten chromosomes, sex chromosomes and they don't know why. It's that complicated so females have ten Xs and males have XYXYXYXYXY and the deal is they're similar to birds in that their X1 chromosome has 11 genes that are found in all mammalian X chromosomes but their X5 gene carries something DMRT-1 and that's found on the Z chromosome of birds. So they sort of share these sex chromosomes with regular mammals and birds but they have five sets.

Josh Clark: And they're superfluous? There's no reason for them to have this?

Chuck Bryant: They haven't figured it out yet and they're still working on that I guess but that was definitely an interesting find.

Josh Clark: And they're 80 percent mammal or they share 80 percent of their DNA with mammals. So that means that they also share some with birds and they branched off with mammals 166 million years ago and went off on their own. That would mean that we possibly are descended from birds as well.

Chuck Bryant: Yeah it definitely raises that question.

Josh Clark: My other question is this. the venom, it's very similar in composition to reptile venom even though it's mammalian produced but they figured out from the platypus genome project that it came up independently.

Chuck Bryant: Really?

Josh Clark: Yeah. They didn't get it from reptilian ancestor. So it's almost like the platypus is this idea that nature has a finite number of tools in its toolkit to handle things like reproduction, defense, whatever. And the platypus represents all these things kind of evolving independently on its own after it branched off 166 million years ago. That's pretty neat.

Chuck Bryant: Yeah. Maybe the platypus therein lies the key to it all. Who knows?

Josh Clark: I sincerely hope not.

Chuck Bryant: It's a very strange creature. At the very least it could help us locate and identify new genes and then sequences that could turn those genes on and off into us.

Josh Clark: Yes. Supposedly ovarian cancer, there's some DNA in ovarian cancer tumors that's found in platypus X chromosomes.

Chuck Bryant: Wow, cool.

Josh Clark: So who knows? That was as far as they got in what I read. They just discovered that so they didn't know what to do with it.

Chuck Bryant: Yeah. I think this is a great load up on this one people for your next cocktail party because everyone's like I get it. They're furry and they've got a duck bill but you can hit them with a bunch of more cool stuff.

Josh Clark: Yeah.

Chuck Bryant: Yeah, what about the spur in the heel? What about these chromosomes?

Josh Clark: How do you like them apples?

Chuck Bryant: Put that in your pipe and smoke it.

Josh Clark: Right. So that's it for platypuses for now until they find some other weird thing about it right?

Chuck Bryant: Yeah.

Josh Clark: You've got anything else?

Chuck Bryant: No.

Josh Clark: If you want to learn more about platypus just type duck bill into the search bar at howstuffworks.com. It will bring up this amazing article and actually no, this was article was written by Conger, How Stuff Works writer on Animal Planet. So check out animalplanet.com and try searching for duck bill platypus.

Chuck Bryant: Very cool.

Josh Clark: Yeah. And I said duck bill so it's time for listener mail.

Chuck Bryant: Before we do listener mail buddy let's talk about stamps.com

Josh Clark: Let's.

Chuck Bryant: Mailing and shipping are a super important part of running any kind of business especially a small business and it can actually get in the way of growing your business if you're a small business because you're always at the Post Office.

Josh Clark: Yeah so use stamps.com instead right?

Chuck Bryant: Exactly.

Josh Clark: With stamps.com everything you would do at the Post Office you can do right from your desk. Buy and print official U.S. postage for any letter or package using your own computer and printer. Stamps.com will send you a digital scale so you don't have to do any of the calculating. This thing does - it calculates the exact postage for you.

Chuck Bryant: It sounds like buddy we may never have to go to the Post Office again if we go to stamps.com or even have to lease one of those postage meters because they're not cheap.

Josh Clark: Chuck, tell them about the special offer.

Chuck Bryant: Well the special offer buddy is promo code stuff. It's a no risk trial plus $110 bonus offer which includes that scale we were talking about and up to $55 in free postage.

Josh Clark: That is awesome so don't wait. Go to stamps.com before you do anything else. Click on the microphone at the top of the home page and type in s-t-u-f-f. It's stamps.com, enter stuff. And now it's time for listener mail right?

Chuck Bryant: Correct. All right Josh. I'm going to call this from Penelope. How simple is that? Hey guys, big fan. I remember when how ginger reassignment words came out. I was a little worried because I fall into the gender queer/transgender spectrum somewhere. That's all she says. As most people who try to talk about it and they're not against the wave usually fail, they'll do a really job and I've had faith ever since then but I have one note. In the CPR podcast, you can [inaudible] right?

Josh Clark: I know because I read this email.

Chuck Bryant: So you're not thinking that? I talked about giving blood and now everyone should give blood. I think in times like these it's important to keep in mind there's a huge population of people in the world who cannot give blood because of the backwards and outdated thinking of the Red Cross or worse. I'm of course talking about anyone who has had sex with a man who has had sex with a man. In that sentence men who have sex with men are indefinitely banned from giving blood.

Women who have sex with an MSM have a one year waiting window for it. I didn't know this. This obviously came from the media created AIDS care that we are just now coming out of. However the Red Cross continues to discriminate to our policy even though their testing abilities that we have are incredibly accurate. To quickly sum it up guys, in the future when you talk about giving blood in your general daily life, on your podcast or wherever, it's a good idea to say something like those who are allowed should give blood.

So I didn't know this and it's always great to get this kind of message out. So thank you. She says love which is very sweet and [inaudible].

Josh Clark: Thanks a lot Penelope. That's awesome. Thank you for pointing that out. It's extraordinarily important I would say.

Chuck Bryant: Yeah and if that's the case I say get with it and allow people to give blood if it's [inaudible]

Josh Clark: You just directed a message to the Red Cross calling them out. If you want to call somebody out through us, we would like to help any way possible. You can Tweet to us at sysk podcasts. You can join us on facebook.com/stuffyoushouldknow. You can send us an email to stuffpodcast@discovery.com and join us at home on the Web, stuffyoushouldknow.com.

Recording: For more on this and thousands of other topics, visit howstuffworks.com.

[End of Audio]

Duration: 26 minutes

Topics in this Podcast: animals