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Mule Gives Birth
!splut writes "Thumbing it's nose as science, a Moroccan mule has given birth. Mules, hybrids between horse and donkey, are normally infertile, due to differences between the number and structure of horse and donkey chromosomes. Nevertheless, for reasons not well understood, fertile mules do occur, infrequently, with some 60 documented live births since 1527."
Are there known hybrids/half-breeds can have normal fertility, as opposed to requiring a "miracle" to occur? This is a sincere question, even though I know full well the trolls that are going to be attracted to this post.
Those who complain about affect & effect on
So what is really interesting is whether the offspring are fertile. If so, then we can start breeding mules from mules, and we have a new species.
And where does the infertility in mules normally lie? Is it a male thing or a female thing? Or both?
I didnt even know her nime months ago.
All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
The Second Foundation barely saved the Seldon plan from the Mule the last time. This kid could ruin everything!
Well, the conditions of where life is created is scientifically known as 'bonking' or 'squelching' or 'doing the dirty' and it is fully expected that a similar route was followed here, although research involving staring at pictures of mixtures of animals is no doubt ongoing, but is having problems obtaining funding.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Your reality is lies and balderdash and I'm delighted to say that I have no grasp of it whatsoever. - Baron Munchausen
A quick google search on Liger and Fertile tells me that male hybrids are rarely fertile. Another page states, "No fertile male ligers have yet been found and it is assuemd all are sterile." Though reading a bit more, there may be some fertile males, or males that are fertile for a brief period.
One possible explantion for this rare occurance, one that I can see, anyway - Horses have 64 chromosomes in their normal diploid state, with haploid gametes having 32. Donkeys have 62 chromosomes in normal diploid state, with haploid gametes having 31. This gives a mule 63 chromosomes. If one gamete had experienced non-disjunction during meiosis (that is, one pair of homologues did not split correctly, giving one daughter cell 2 copies of a chromosome, and one none), a mule could have 62 or 64 chromosomes (depending on which gamete it received). This is not a very rare occurance, Down Syndrome or Kleinfelter's Syndromes in humans (trisomy 21 and XXY respectively). While most cases of non-disjunction produce abnormal offspring, in humans, for example, an XXX female is completely normal, except for a usually smaller stature. A case like this, where the offspring IS normal, is relatively rare, and a similar situation could be occuring in these fertile mules.
Yeah! And what's the deal with this mule having a thumb? Where'd she get that from?
They who would give up an essential liberty for temporary security, deserve neither liberty or security
Really, what it's doing is thumbing it's nose as science teachers; those people who told us that mules are sterile and heating solids always expand.
I understand your point.
Your reality is lies and balderdash and I'm delighted to say that I have no grasp of it whatsoever. - Baron Munchausen
Nice troll, but the existence of natural phenomena that are not understood in no way represents a "failure" of science. It would *only* be a failure if science was a system of belief that purported to explain everything about the Universe (like, say, religion). It is not such a system.
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
The truth is that speciation is not very well understood. In many ways 'species' is a convenient abstraction - we humans like to put horses and donkeys into two discrete buckets and not think much about anything in between. In reality there is no law of nature that says that all living entities must belong to exactly one of our convenient buckets.
The 'infertile children' definition works pretty well, but it is not perfect. Another problematic example is that of a species of birds that live in different territories around the globe. The birds can mate with other birds in their own or in adjacent territories. In other words, the birds in the first territory can mate with those in the second territory, and those in the second with those in the third, and so on all the way around the globe - and finally the birds of the last territory can again mate with those in the first. However, it turns out that the birds cannot mate with birds several territories away. Our convenient species definition breaks apart.
Tor
> Or perhaps that's just a legend?
An urban legend, with emphasis on the urban.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
"The donkey has 62 chromosomes (31 pairs), the horse 64 (32 pairs) and the mule and hinny each have 63 chromosomes - of which many pairs are unevenly matched. It is not just the number of chromosomes which is different in donkeys and horses, but their structure: they have developed slightly differently over evolutionary time....The donkey and horse chromosomes are almost completely unable to pair up."
It's amazing that mules turn out as well as they do. If carrying heavy packs all day and being beaten daily by a bowlegged man with whiskey breath is your idea of turning out well.
Now that's some half-assed science.
"We must cultivate our garden." -- Voltaire
My parents met in Venezuala, working for shell oil, in the late 1940s. Shell had a company store where the North American employees could buy stuff you couldn't normally get in Venezuala. They had North American bungaloes for the North American employees. They had a little school with a North American teacher (my mom) for their children.
Like other North Americans my parents had a local cleaning lady. Unlike some of the other North Americans my parents learned Spanish.
My mom told how she taught Dahlia, how to prepare potatoes North American style. Including baking them. You peirce the skin so the steam can escape. I know most people do this by poking them with a fork. But in my family we cut a small X in the skin.
My mom's spanish wasn't yet sufficient to explain why you cut an X however.
A couple of days later there was an explosion in the kitchen. Dahlia is standing over the oven door, covered with exploded baked potatoe.
She was hysterical, and very apologetic. She told my mother that she realized she must have been very religious. But, she was in a hurry, and just this once, she thought that God would forgive her if she blessed the potatoes by putting the sign of the cross in them after they were baked, not before.
Dahlia couldn't explain this explosion, except to think it was a miracle. God punished her for not blessing the potatoe with a cross.
So, was it really a miracle? Of course not. Does an inability to explain a phenomenon mean that it is the reuslt of supernatural intervention? Of course not. Not with exploding potatoes, or with unexplained births.
I like breaded mule, especially the chicken-fried I had at Outback. Oh, you mean breeding!
Sorry, corny joke. Had to do it. So sorry. :)
A fertile M.U.L.E. - we could have used one of those on planet Irata. ... wonder if I can genetically engineer them to be born already outfitted for Smithore?
The beeb and the British Mule org may have said mules are infertile because they have an odd number of chromosomes. But I am skeptical.
Here is an excerpt from a page about the Przewalski Horse
So, even if this site is mistaken to say that the 65 chromosome hybrid is fertile, what if you crossed a 62 chromosome Ass with a 66 chromosome Przewalski's Horse? That hybrid would have 64 chromosomes. Would that make it fertile?
Who's this person called Science? I know some people who call them scientists and they have all sorts of different opinions about things. But I've never met this person called 'Science'.
-- SIGFPE
Normally a mule has 63 chromosomes according to the article (presumably 62 paired donkey/horse and one paired horse/horse).
... but then again, there wasn't much in the article either.
However, this mule suffers a form of "mule Down's syndrome" - she only has 62 pairs. The father is a donkey. There is a match in the number of chromosomes.
So, what is considered a genetic disability in humans could possibly be considered a genetic advantage in mules.
Note: no science whatsoever backs this theory as far as I know
I find the science fascinating. Likewise, people's inability to use the English language.
This was more a case of my inability to proofread my own typing.
I seem to have a typo every time I get a story accepted. You'd think I'd learn...
The angel in the oatmeal.
There are three different species of Zebra, including the Quagga , which genetic analysis shows to be a subspecies of the Plains zebra.
Just because something is unlikely doesn't mean it is impossible, and science does not claim otherwise. Thumbing its nose at science? That's stupid!
The Uncoveror: It's the real news.
... not blessing the potatoe with a cross.
Great story, Mr. Vice President!
Horse mother, donkey sire - offspring is a mule. Donkey mother, horse sire - offspring is a hinny. Genetically indistinguishable from a mule. I presume the two different names predate modern genetics.
Mules are stronger, and more intelligent than horses.
Like mules, a hybrid of a zebra and a horse, or a zebra and a donkey, is infertile. Or a hybrid between any of the three species of zebra.
Fans of breeding exotic hybrids have dreamed up all kinds of "cute" names for the different crosses. Seems annoying to me.
Breeding exotic hybrids of endangered species seems very irresponsible to me. But there are people who do it. It seems to me that breeding a Liger or Tigon means you are wasting the reproductive potential of the parents. The Quagga is a recently extinct subspecies of Plains Zebra. There is a project to find Plains Zebras with the most Quagga like characteristics, and breed them, to try to restore them.
This seems like a bad idea to me too. It seems to me that it makes more sense to husband the remaing genetic heritage of the Plains Zebra.
The sixth surviving equid is the very rare Przewalskis' Horse. Extinct in the wild. 150 survive in zoos. Originally found in Mongolia. It is not too late to try to preserve this animal's genetic heritage.
Close.
With horses, the male is a stallion, the female is the mare. With donkeys, also known as the ass, the female is the jennet or jenny.
The hybrid of a stallion and a jenny is a "hinny".
OK.. Blowing *my* chance to mod to set things straight..
:)
"What you're saying amounts to people that used to bash Christopher Columbus for believing the world is round".
Actually, Queen Isabella knew *damned* well that (a) the world was round (b) the circumference was around 25,000 miles (c) that going east it was some 7,000 miles and (d) ships of the day didn't have the capacity to carry supplies for a trip of 18,000 miles the OTHER way. Chris Columbus thought the circumferences was 12,000 miles, and thought a ship could carry supplies for a 5,000 mile trip.
So Isabella finally shut him up by sending him off with 3 leaky ships crewed by prison scum, figuring if they never came back she'd not be sorry. And sure enough, 5,000 miles later Chris was running out of food when he found unexpected land. Fool that he was, he went to his deathbead truly convinced he *had* made it to the Orient.
Call Isabella the first of the high-risk venture capital financiers...
Could it be possible that that mules don't reproduce very often due to the fact that no one tries to reproduce them due to the fact that its "common knowledge" that mules can't reproduce?
A horse has 64 chromosomes and a donkey has 62, so a mule is left with 63, an uneven number which cannot divide into chromosome pairs. This should make a mule unable to reproduce.
So how many does this baby mule have? Did it manage to end up with an odd number, or did it end up with an even number due to one of its mule parents having the mule equivilent of downs syndrome?
On the contrary, maybe that's the secret, Taco's all like "wow this was the first submitter today who can spell" :)
Is it? Can you explain this to me?
First, let me restate this, so I am sure we mean the same thing. You are saying that paired chromosomes are necessary for an animal to breed true with its peers, is this correct? You are not saying that having paired chromosomes are necessary for an offspring to be born, because mules obviously don't fulfill this condition.
So, how did the proto-equid, that was the ancestor of both Asses and the Horse split into two species with different numbers of chromosomes?
So, what about Down's syndrome individuals, who have an extra copy of chromosome 21? They don't fulfill your requirement for an even number of chromosomes. Yet I don't believe they are sterile.
Like MS-Windows programs, our chromosomes contain a lot of code bloat.
I heard a lecture about this, when I was in high school. So this info may be incorrect, and I would welcome correction. That lecture included slides of individuals born with chromosome abnormalities. Our chromosomes vary in size. And they are numbered in order of size. The lecturer showed some individuals with an abnormality on a larger chromosome. She said that these individuals were more profoundly affected and had more health problems and more profound cognitive challenges than Down's Syndrome individuals. She said that abnormalities on the larger chromosomes result in problemso profound that the children are spontaneously aborted before they come to term.
Then there are chromosome abnormality of the X and Y. Turner's syndrome women lack a sex chromosome. They have a single X and no Y. They are of normal intelligence. But they never go through puberty, so they can't have children. There are people who have XXY and XYY. I don't believe they are sterile either. Another slashdotter said something about XXX women - women with three X chromosomes.
Since that lecture I have heard that some Down's symdrome individuals have only a fraction of the extra 21, and that there are less profoundly affected than individuals with a full extra chromosome 21.
Genes slip around. They slip from chromosome to chromosome. I saw a science documentary about how genes were slipping from the Y to the X. I am not a molecular biologist, but I imagine that 61 of the 62 chromomosomes of Horses and Asses correspond, and that sometime after they split into different species one of the chromosomes split in two. If this was the case, there would be genes for the same traits in the chromosomes from both parents, even though they had them on different chromosomes.
There was an article in Scientific American, on mule fertility about 45 years ago. It advanced a theory about Mule fertility, that Mules produce gametes, eggs and sperm, but that almost all of them contain a mixture of Ass and Horse chromosomes. And those would be no good. But occasionally a gamete is produced that has all the gametes from a single parent. IIRC the theory was that that gamete could be fertilized and brought to term. That offspring would be pure Horse or pure Ass. "One in million" is the estimate of how often a mule brings an offspring to term. Check my math. If this theory is correct
Here is something I don't understand. That documentary said that some of the genes on the Y are duplicated dozens of times. So, why does the mere single extra copy of genes in chromosome 21 cause the profound manifestations of Down's? Does each gene contain the molecular equivalent of an instruction pointer, or a map of bad sectors?
Here is an example . Most of the most widely used cereals are hybrids that breed true. However, from memory, I think that the number of chromosomes of triticale and similar hybrids is the sum of the number of chromosomes in the parent stock, not the average.
If the name triticale rings a bell it may be because Captain Kirk had to make an emergency delivery of QuadroTriticale in an old Star Trek episode.