Platypus, platypus, platypus, platypus

| 70 Comments


Platypuses at Berkeley’s Museum of Vertebrate Zoology


The platypus is currently tied for my favorite mammal (along with hedgehogs and manatees). Platypuses have a lot of unique characteristics, but one of the features I find most fascinating is their sex chromosomes. Before a post about their chromosomes, there’s a few things we need to clear up.


1. The platypus is not a “cross” between a duck and a beaver.
Because of its unique features, there is a lot of confusion about the platypus. The platypus is not some strange hybrid. A duck and a beaver cannot produce an offspring together. The population of platypuses evolved, like all other living organisms.

Upon closer inspection, looking at the picture above, the platypus bill looks very little like a duck bill at all. The platypus bill is wide and flat, and appears to be more leathery than the hard duck bill.

Spot-billed Duck RWD6
By DickDaniels (http://carolinabirds.org/) (Own work) via Wikimedia Commons

And, even though popular cartoons continue to draw its tail as if it were beaver-like, the platypus tail is relatively short, and is covered with soft brown fur, not at all like a beaver’s large hairless tail:

American Beaver
The beaver has a large, flat, hairless tail. By Steve, Washington, DC via Wikimedia Commons


2. The platypus is not the ancestor of modern mammals, it is a modern mammal. 
Although it lays eggs, and doesn’t have breasts or nipples, the platypus is still classified as a mammal. Platypuses are part of the group of egg-laying mammals called “monotremes.” These are not “proto-mammals.” Nor are they “primitive”. Monotreme mammals have been evolving for the same amount of time as all other mammals. As humans we share a common ancestor with platypuses, approximately 220 million years ago. That doesn’t mean that it isn’t useful to understand more about the platypus, but interpretations should be careful not to assume the platypus has maintained the ancestral state of all mammalian traits.

3. The platypus is not the only egg-laying mammal. 
In addition to the platypus, there is another group of monotreme mammals that lay eggs: Echidnas. Echidnas and platypuses diverged from one another about 64 million years ago. While they share some characteristics that are unique to monotreme mammals (relative to other mammals), such as egg-laying and oozing milk out of mammary pores instead of having nipples, the two groups of species have accumulated many differences. Perhaps one of the most notable is that there are at least four species of echidna, and only one species of platypus.

Other cool echidna features include their body covering which includes a mixture of course hair and dense, pointy, spines.

Echidnas at Berkeley’s Museum of Vertebrate Zoology

Echidnas also have long durable nails that they use for digging in the sand and dirt.

Check out those nails.


4. Platypuses are about the size of a house cat
I don’t know why, but when I was growing up, I always imagined that platypuses would be fairly large critters - not unlike a recently discovered branch in the platypus tree that went extinct 5-15 million years ago. Turns out, modern platypuses are actually about the size of a house cat. You can see the pictures below  with my hand next to them.

Not so giant platypus.

If you want to see a live platypus (which I really, Really, REALLY do!!), check out this video of some people hand feeding a platypus.





70 Comments

Well unless you can show me a cross between a duck and a beaver, then evolution can’t be true. What’s that? Oh, I meant a cross between a duck and a crocodile. Yea, that’s it, that’s what I meant. What’s that? Oh, … never mind.

Another nifty factoid: the males are venomous, a trait which is also fairly rare in mammals.

I get a 404..Not Found for this: If you want to see a live platypus (which I really, Really, REALLY do!!), check out this video of some people hand feeding a platypus.

Thanks for the comment - I fixed it. Originally, I had tried to embed the video, but that didn’t work. When I made it into a link, I forgot to take the embedding code out.

the platypus bill looks very little like a duck bill at all.

And only the platypus gets the electric bill.

Glen Davidson

DS said:

Well unless you can show me a cross between a duck and a beaver, then evolution can’t be true. What’s that? Oh, I meant a cross between a duck and a crocodile. Yea, that’s it, that’s what I meant. What’s that? Oh, … never mind.

Platiduck?

You couldn’t at least produce a duck whose distribution overlaps the platypus? Or the beaver, for that matter? Give hybridization a chance. Maybe an otter would be a better choice than beaver.

Are the Platypuses pictured at Berkeley’s Museum of Vertebrate Zoology dead or alive?

Henry J said:

DS said:

Well unless you can show me a cross between a duck and a beaver, then evolution can’t be true. What’s that? Oh, I meant a cross between a duck and a crocodile. Yea, that’s it, that’s what I meant. What’s that? Oh, … never mind.

Platiduck?

No man, duckapus. What is ya, ignorant?

Paul Burnett said:

Are the Platypuses pictured at Berkeley’s Museum of Vertebrate Zoology dead or alive?

They are dead, taxidermied. Oh, if they were alive, I would probably never leave.

But, what do they taste like?

patrick.j.may said:

But, what do they taste like?

Chicken?

DS said:

Henry J said:

DS said:

Well unless you can show me a cross between a duck and a beaver, then evolution can’t be true. What’s that? Oh, I meant a cross between a duck and a crocodile. Yea, that’s it, that’s what I meant. What’s that? Oh, … never mind.

Platiduck?

No man, duckapus. What is ya, ignorant?

And a Platypus with attitude is.……?

This thread proves that there needs to be a way to up-rate (and probably down-rate) comments on PT.

MJHowe said:

DS said:

Henry J said:

DS said:

Well unless you can show me a cross between a duck and a beaver, then evolution can’t be true. What’s that? Oh, I meant a cross between a duck and a crocodile. Yea, that’s it, that’s what I meant. What’s that? Oh, … never mind.

Platiduck?

No man, duckapus. What is ya, ignorant?

And a Platypus with attitude is.……?

A platitude?

M. Wilson Sayres said:

Paul Burnett said:

Are the Platypuses pictured at Berkeley’s Museum of Vertebrate Zoology dead or alive?

They are dead, taxidermied. Oh, if they were alive, I would probably never leave.

Maybe carried out on a stretcher by paramedics after your second or third encounter with the male’s poison spurs.

Behold the duck-billed platypus/That’s native to Australia!/As mammals go, not quite like us/But certainly no failure.

Not primitive, not left behind/Adaptions? Yes, they’ve gottem/That bill is brilliantly designed/For feeling on the bottom.

Designed? Well, clearly, that’s not right./I meant “evolved”, no, really./And “bottom of a stream at night.”/Not lewdly touchy-feely.

But that’s our language. It’s a tool/that tends to the assumption/that “common sense” will always rule,/and all you need is gumption./Nor has equivoque occurred,/ for every single separate word/Has just one meaning. (That’s absurd.)

To this YEC creationist the platypus is case in point of wrong, too quick off the hip for the old ones, classification systems. Its only unique is presumptions that like traited creatures are from like origins or just should be lunped together. Laying eggs is no big deal in the animal kingdom. Its not a defining trait of heritage. The platypus is just some kind of otter with adaptions for a niche it migrated too back in the day. I understand the “beak” is sensitive for finding food and thats all it is. So the creature is always in the water and couldn’t watch its kids like other creatures etc. Like marsupials its just minor differences from relatives that lived elsewhere on the planet but now extinct. Indeed evolutionists used to say it was between reptiles and mammals and so primitive. Its not primitive whatsoever. Egg layers is just in a spectrume of a rathyer common plan of reproduction. Some snakes lay eggs and some birth without them. Its no big deal. The platypus, I think, is not a strange aberration but a revelation of the true equation that classification systems based on like traits is purely speculative. As the bible says there is just kinds. no mammals or reptiles or dinosaurs.

And speaking of absurd…

I can’t help but thinking Byers is a spoof. His “mistakes” seem artificial and contrived, don’t you think?

Not to mention platitudes… So the platypus is just ‘some kind of otter’ wearing a bush hat hung with corks tied to pieces of string - works for me.

Fascinating article! Thanks for posting it.

This thread proves that there needs to be a way to up-rate (and probably down-rate) comments on PT.

True, but there is a bathroom wall.

Surprisingly, Byers is making more sense here than usual, if only unintentionally. The comment about “kinds” is silly (the notion suffers far worse problems than “species”), but it is certainly true that there are a spectrum of features in the animal kingdom, which often blurs the dividing lines between species. Looked at historically, species do run together. But what Byers is describing is a definition of Evolution, not a problem for it. In contrast, his observation of a spectrum of features completely contradicts his conclusion of distinct “kinds”. Were the notion of “kinds” true, one would expect to see clear dividing lines, distinct clusters of features, rather than spectra.

Indeed evolutionists used to say it was between reptiles and mammals and so primitive. Its not primitive whatsoever

Not being primitive–which no modern organism is (hence the term “modern”)–doesn’t mean that it isn’t somewhat intermediate between reptiles and other mammals. And it was always just “somewhat” anyhow, and only relative to “other mammals,” as we likely are intermediate between monotremes and reptiles in other ways.

I know, troll-feeding is frowned upon. But the troll does say things that creationists think and may agree with, so the ignorance needs pointing out.

Oh Byers, explain the sex chromosomes of monotremes, and why they have an autosome homologous with our X-chromosome. Explain why the earliest mammal group to branch off from other mammals has the earliest reproduction method, that of egg-laying. Explain vestigial teeth in juvenile platypuses, electroreceptors in the echidna bill which have no apparent function, but do evolutionarily follow by echidnas branching off from aquatic platypuses. Explain the non-functional spurs in echidnas, like those that in male platypuses deliver venom.

Rhetorical, of course, since Byers and other creationists aren’t interested in explaining anything, but only in destroying evolutionary explanations that do exist, ignoring anything that doesn’t fit their quest to destroy knowledge.

Glen Davidson

https://me.yahoo.com/a/JxVN0eQFqtmg[…]X_Zhn8#57cad said:

…ignoring anything that doesn’t fit their quest to destroy knowledge.

Glen Davidson

Knowledge is atomic and unproven.

[parodying an earlier statement by Byers]

There are platypus jokes. A platypus walks into a bar and tells the bartender,”Got any shrimp?” The bartender says ,”No, now go away!.” The platypus walks in to the bar again and says, “Got any shrimp?” The bartender says,”No and if you ask me that one more time I’ll staple your webbed feet into the floor!” The platypus walks into the bar again and says,”Do you have any staples?” And the bartender says,”No.” Then the platypus says,”Got any shrimp?”

Syntax Error: mismatched tag at line 9, column 2, byte 268 at /usr/local/lib/perl5/site_perl/5.16/mach/XML/Parser.pm line 187.

Robert Byers said:

Egg layers is just in a spectrume of a rathyer common plan of reproduction. Some snakes lay eggs and some birth without them. Its no big deal.

But how they go about doing this is a big deal. Do any snakes have a placental system that exactly looks like most mammals’? No. What it looks like a modifcation to the more typical egg-laying plan. Even the fully viviparous species include key differences (such as a yolk sac) that mark the adaptation as being closer to egg-laying than to placental mammals’ system. This indicates that live-birthing snakes are more closely related to egg-laying snakes than they are to live-birthing mammals.

Oh, but I forget that Byers doesn’t allow us to draw any inferences about relatedness for some reason. That’s taboo, or something.

The platypus, I think, is not a strange aberration…

Neither does anybody here. It’s not treated as an aberration in biology, but rather as a fine example of a whole host of mammals that are now mostly extinct.

… but a revelation of the true equation that classification systems based on like traits is purely speculative.

I know I cut out most of your post, but even with the rest of it and pasting the two clauses of this sentence back together, this conclusion is a complete non-sequitur. It doesn’t follow logically from anything you’ve said, just repeats earlier assertions without connection to earlier premises. In fact by reading your post fully, one can’t help but recognize the great lengths you go to simply to ignore the obvious conclusion.

As the bible says there is just kinds. no mammals or reptiles or dinosaurs.

So what?

Robert Byers said:

corbsj said:

To throw in another cool platypus feature they also have a 6th sense electroperception!

A platypus will keep its eyes firmly closed under water. It uses its bill to help scan and dig up the mud and is quite sensitive to touch. However it also highly sensitive to small electric fields. The ability is similar to sharks but evolved completely separately of course.

http://monash.edu/news/releases/show/2

So the platypus is a mammal that has a bill, fur, lays eggs, has venom and radar…

I didn’t know that but its cool for ID or YEC creationists. The case is made about how its unlikely radar evolved in diffeent creatures and so rather its from other biological mechanisms.

You got the MATH to show how ‘unlikely’ radar evolved in different creatures ?

All that is needed for echolocation is the ability to produce sounds, and the ability to hear them.

IIRC, the cave birds have a rather crude form of echolocation, whereas bats and dolphins have highly developed ones.

There was a paper comparing the Prestin protein in echolocating and non-echolocating bats and cetaceans.

If you compare the DNA sequences, the echolocating bats group with the other bats, while the echolocating cetaceans group with other cetaceans and bovines (another artiodactyl).

However, if you compare the PROTEIN, then the echolocating animals are grouped together.

This is an example of convergent evolution (but Booby will claim that the groups magically willed themselves to gain the ability somehow. Or something even sillier).

For this YEC its exactly as expected. Radar in bats, whales, some cave birds, and now the platypus explains radar as a option for lots of creatures from innate triggers in the bodies. Hard to believe but most likely true.

Only if one is willfully IGNORANT of centuries of real world biology.

Since your Magical Sky Pixie works in “mysterious ways”, HOW CAN YOU ACTUALLY CLAIM anything is as expected from Him/Her/It/Them ?!

The platypus uses electroperception - NOT ‘radar’.

Evolution works by modifying what an organism already has - there are very few novelties.

Are you SERIOUSLY implying that those diverse groups magically willed themselves to gain an ability ?!?!

Quick ! Will yourself to have a completely different reproductive system !

First you’ll have to know WHICH genes to modify, and exactly HOW to change them.

Or does it work by magic ? “Well, the critter doth will itself to change, and this magically alters the magical morph field, which magically alters the DNA (which is irrelevant because I don’t know anything about such things !!) because a Magical Sky Pixie magically wills such things to be possible !!!!1!!!1!!” ?

Not from convergent evolution coming up with the same idea.

And you ‘determined’ that HOW, exactly ?

Oh, right - imposition of willful ignorance and arrogance. If ** YOU ** can’t see how something could happen naturally, then it be impossible !!!

Robert Byers said:

corbsj said:

To throw in another cool platypus feature they also have a 6th sense electroperception!

A platypus will keep its eyes firmly closed under water. It uses its bill to help scan and dig up the mud and is quite sensitive to touch. However it also highly sensitive to small electric fields. The ability is similar to sharks but evolved completely separately of course.

http://monash.edu/news/releases/show/2

So the platypus is a mammal that has a bill, fur, lays eggs, has venom and radar…

I didn’t know that but its cool for ID or YEC creationists. The case is made about how its unlikely radar evolved in diffeent creatures and so rather its from other biological mechanisms. For this YEC its exactly as expected. Radar in bats, whales, some cave birds, and now the platypus explains radar as a option for lots of creatures from innate triggers in the bodies. Hard to believe but most likely true. Not from convergent evolution coming up with the same idea.

No.

The other examples you mention use sonar. Completely different mechanism based on sound.

Interestingly the other mammal that has this electroperception is the Echidna who is also a monotreme. Yet another trait that links them despite the animals looking significantly different. I’m not aware of the ability existing in any other mammals. So it has not evolved in many different creatures.

So even though the Echnida and the platypus both lay eggs, have the same spur on their back leg on which they secretes a substance (although the echnida’s is not venomous), have milk patches rather than nippples, have a four headed penis and have no teeth, I suspect you would say they are not in anyway related and the Echidna is just a hedgehog or a porcupine with a few additional minor traits.…

Bobbity boobity bobbidty boop.

PA Poland said:

This is an example of convergent evolution (but Booby will claim that the groups magically willed themselves to gain the ability somehow. Or something even sillier).

IIRC, it is in fact Ray’s opinion that animals “will” themselves to gain various abilities; that it is the animals themselves who are intentionally creating variation in themselves (not just their offspring). That’s his (apparently unique) version of “intelligent design” creationism. I think Robert is more of the six-literal-day YEC variety.

The metatherian placenta is different in structure from the eutherian placenta. The former involves the chorion only, while the latter involves both the chorion and the allantois.

Sorry folks but no more discussions. WHY??????? It was interesting, on thread, and part of the whole purpose behind the forum. Oh well at least a little conversation on interesting matters in biology. I know how that Freshwater guy feels !! Except telling the family about the loss of income!

Bobby,

Your particular brand of “discussion” is only allowed on the bathroom wall. Go there if you dare. I am sure that you will get all of the “discussion” you can handle. This thread is for grown ups.

Just go discuss the matters at the Bathroom Wall you big doof.

John Harshman said:

The metatherian placenta is different in structure from the eutherian placenta. The former involves the chorion only, while the latter involves both the chorion and the allantois.

Not exactly. A yolk sac is an extraembryonic membrane seen in all vertebrates. Amniotes (mammals birds and reptiles) add three more: amnion (protects embryo), chorion (lines the internal egg surface), allantois (originally for waste storage).

All amniotes have the outgrowth of these membranes, and monotremes (within the egg) show a condition rather like that of other amniotes. In placentals, a “placenta” (i.e., a connection between the embryo and the maternal tissues) is first formed via a connection of the yolk sac with the chorion (the “choriovitelline” placenta). Soon after, this is replaced with a placenta formed from a connection of the allantois (which grows out later in ontogeny) with the chorion (the “chorioallantoic” placenta).

In marsupials (in comparison with placentals, monotremes, and other amniotes) the outgrowth of the allantois is suppressed. The period of gestation is also brief. Thus for most marsupials, the only placenta is the choriovitelline one. In some marsupials, convergently (koala+wombat on the one hand, and bandicoots on the other), and via rather different means, there is an outgrowth of the allantois at the end of gestation to produce a brief chorioallantoic placenta.

The important point here is that the outgrowth of the allantois is delayed or suppressed compared with all other amniotes. Thus the lack of a placental (eutherian) like chorioallantoic placenta is actually a *derived* character (aided and abetted by the short gestation time, not exceeding a single estrus cycle).

I was lucky enough to swim with one platypus (Numi) at Healesville Sanctuary a few weeks ago.

It turns out that they’re more inquisitive than a kitten, quicker than a sneeze, and love having their artmpits (legpits?) scratched! And they’re more endearing than a baby Black Rhino.

And astonishingly friendly, once they’ve figured out what you’re up to. (At least, in a 50,000 gallon tank, anyway.)

Best 35 minutes of my insignificant life.

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This page contains a single entry by M. Wilson Sayres published on November 15, 2013 7:24 AM.

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