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A friend has recently returned from the Galapagos and has pointed out an anomaly. He tells me that according to Darwin's account the "swimming iguanas" (I don't know their zoological name) are a unique evolutionary development from the land based ones. But the Galapagos islands are volcanic in origin, hundreds of kilometres off the Ecuadorian coast and there never was a land-bridge.
His first question, naturally, is how in the hell did they get there? His second is what evolved from what?
You don't suppose that there is anything in Creationism, do you?
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| berniegreen wrote: | | So far as I know, all horses can interbreed with all other horses and produce non-sterile offspring. I remember reading somewhere that there was some doubt as to whether that included the Prezwelski (spelling?), but I don't think that anybody has put that to the test. |
Przewalski's Horse has 66 chromosomes. Other horses have 64 chromosomses.
The 64 chromosome horse can breed with the 66 chromosome horse and produce a horse with 65 chromosomes. But the 65 chromosome horses cannot breed with other 65 chromosome horses and produce offspring due to the odd number of chromosomes. The 65 chromosome horse can breed with a 64 horse and produce a 64 chromosome horse with very few of the 66 chromosome horse characteristics. Some biologists consider them the same species. (It's also interesting to note that the Somali ass sometimes has 64 chromosomes.)
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Mick Harper
Site Admin
In: London
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I am deleting all the soppy philosophising.
Bernie, we refer to each other by Christian names or other terms-of-affection. Unless for comic effect, irony etc. We don't go in for all this faux-politesse that others are so fond of. You have to put up with Ishmael's rudeness without rancour because he is clinically insane (but worth keeping around for other reasons) but otherwise you will be protected from others' waspishness.
On the substantive/substantial matter about horse-cultures, the point I was trying to make was that only two cultures were totally dependent on the horse (the Mongols and the Plains Indians) whereas all the others you mention just regard the horse as more-or-less important for various purposes. There's no need to go into detail since I assume you will agree that Mongols and Indians are linked together peculiarly and this link is either significant or coincidental.
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Mick Harper
Site Admin
In: London
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| On this basis, the orthodox account would seem highly probable and not in need of challenging. |
Bernie, using your experience and expertise, would you say that escaped Spanish cavalry/draught horses could or would produce a feral population of pinto ponies in a few generations? (You choose.)
And since Australian brumbys would seem to be exactly the same as the North American escapees (ie cavalry/draft European horses gone feral for a few generations) how similar are they to pinto ponies. And if not, why not?
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DPCrisp
In: Bedfordshire
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| Assuming ideal habitat, if you start with a theoretical bunch of 5 escapees (1 stallion and 4 mares)... Horses will normally stay within a 5-10 kilometre radius of their water-holes |
What is your experience of escaping horses? Is it not true that they will run around rather than run away? Aren't they intensely social and unlikely to isolate themselves? What are the chances of a breeding group breaking away from the herd, or that individual escapees would meet up?
What constituted a herd in the situation we're talking about? Big enough to need to fragment, as it might in the wild? And where was it: were the conditions anywhere near ideal between where they are supposed to have escaped from and the Great Plains?
| So far as I know, all horses can interbreed with all other horses and produce non-sterile offspring. |
The question of what species are persists then... but this is no surprise if all modern horses descend from domestic horses.
| Merely that size between, say, 14 hand and 16 hands can vary quite a lot over a relatively short time duration. |
But that was under captive breeding conditions. In the wild, wouldn't this mean the size range can increase quickly?
If they get consistently larger or smaller, you can bet a selection pressure will be picked and treated as obviously the cause.
How much is 2 hands compared to the full range of sizes? Couldn't this be interpreted as "you can hardly get any variation from a limited stock, so the American mustangs can't have come from Spanish horses?"
| It is also interesting to note that there does seem to be a "regression to the mean" with feral horses. Today's mustangs and brumbys (which are the world's two largest groups of feral horses) are all generally about 14.5-15.0 hands no matter what was their original founding stock. |
Please elucidate. Doesn't this challenge what is "known" about these founding stocks?
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DPCrisp
In: Bedfordshire
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| There was a programme on TV called 'Sex and the Neanderthals' which proposed that Neanderthals are still with us, in other words they were assimilated by Homo Sapiens. This is predicated on the idea that different species interbreed when circumstances encourage it and the theory explains human diversity over a period of 40,000 years. |
I missed most of this, but mostly it reminded me that we don't seem to have any sensible definition of "species". Perhaps, contrary to appearances [pun intended] species are not well defined. They slapped an arbitrary-sounding 2,000,000 year(?) limit on the separation of kin that could still interbreed.
I'm not sure that helps one way or the other with horses when the genetic evidence is clear: diversity down to c.12,000 years ago and 'coversity' after that.
| they roam across prescribed areas, much as our Dartmoor and New Forest ponies |
A case in point. Anything less like running away I have never seen.
| They can be caught and corralled at the appropriate time, much as the Inuit reindeer. |
How does that compare with zebra behaviour: they're said to be untameable.
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DPCrisp
In: Bedfordshire
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| Przewalski's Horse has 66 chromosomes. Other horses have 64 chromosomes. |
But chromosomes can vary in human beings... and plants can hybridise with two full sets... How do we know this isn't an odd case of a branch of the family changing recently? (I don't know how that could happen recently or suddenly any more than I get how it's supposed to have evolved naturally.) In all other respects, they look like horses more than anything else, right...?
What does their mtDNA say? What do other equids have?
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| DPCrisp wrote: | | Przewalski's Horse has 66 chromosomes. Other horses have 64 chromosomes. |
But chromosomes can vary in human beings... |
Yes, but in such cases the person is almost always infertile (Klinefelters's, Turner's syndrome, etc.) One man with Down Sydrome has been reported to have fathered a child. A few women with Down Sydrome have given birth to normal babies, but the number is small. I don't think it's significant.
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| Mick Harper wrote: |
On the substantive/substantial matter about horse-cultures, the point I was trying to make was that only two cultures were totally dependent on the horse (the Mongols and the Plains Indians) whereas all the others you mention just regard the horse as more-or-less important for various purpsoes. There's no need to go into detail since I assume you will agree that Mongols and Indians are linked together peculiarly and this link is either significant or coincidental. |
I agree that those two are the only two "major" ethnic/cultural groups, but there have been and are some interesting sub-cultures such as the gauchos of the pampas. --- minor point. And yes I do agree that they are linked and that the link is significant. I think it comes under the heading of filling a niche in the environment.
But there are also two very important cultural differences between the two groups;
1.The Plains Indians were principally hunter/gatherers with a bit of gardening on the side. The Mongols were/still are principally pastoralists, also with a bit of gardening on the side.
2. The Plains Indians (a bit like the indigenous Australians) were never sufficiently cohesive/motivated to embark on major territorial conquest or the creation of "empire".
And if you want to get onto the idea of linked descent, I do need to point out that they don't look anything like each other !!!
And, lastly, I don't believe that anybody has ever suggested that Altaic is at all related to any of the languages of the Plains Indians of which there are about 4 or 5 main ones, I think.
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| Mick Harper wrote: |
Bernie, using your experience and expertise, would you say that escaped Spanish cavalry/draught horses could or would produce a feral population of pinto ponies in a few generations? (You choose.) |
The conceptual problem here is that your paradigm is wrong. The Spaniards took with them, initially, just "horses of war" it is true. But once they were established they also took out fine riding horses suitable for the ladies, such as the Fino Passo breed and also "pets" such as the miniature Falabella. The Pinto, the Overo, the Tobiano, the Palamino (also known as the Isabella) all have well documented European pasts and were all taken to the New World by the Spanish as breeds bred for their appearance and temperament as riding horses.
The only horse breed deriving from the Native Americans is the Apaloosa.
| Mick Harper wrote: | | And since Australian brumbys would seem to be exactly the same as the North American escapees (ie cavalry/draft European horses gone feral for a few generations) how similar are they to pinto ponies. And if not, why not? |
Again we need to correct the paradigm. There was no extensive use of military/cavalry across Australia. Most of the brumby stock originates from escaped "Walers" and "Stock Horses" These are now distinct and recognised breeds. The Waler tends to be a light carriage or heavy riding horse analagous to the Cleveland Bay in England or the Holsteiner in Germany. The Australian Stock Horse is like a rather more rugged Thoroughbred. The principal draught horse in Australia is/was the Clydesdale. Very few of them escaped (were allowed to escape). They were too precious.
Finally, you should also be aware that Pinto (of which there are two sub-classes, Overo and Trobiano) is merely a colour breed. Popular wisdom has it that the Plains Indians really valued the Pinto colouration for their war parties because of the camouflage effect and so by crossing and re-crossing with a number of captured stallions they developed sizeable herds of, what are known in the trade as, Paint horses.
Sorry if this sounds all rather mundane and boring, but sometimes the truth is just like that.
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Ishmael
In: Toronto
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| Mick Harper wrote: | | You have to put up with Ishmael's rudeness without rancour because he is clinically insane (but worth keeping around for other reasons) |
When was I rude or rancourous?
Sometimes, I just don't understand you all. You read things into my words that were never put there by me.
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Mick Harper
Site Admin
In: London
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Bernie, erase what you know. Assemble all the horses that the Spanish took to Mexico. Let them escape by some random (or other, if you can think of one) process and mix (or not, you choose) these escapees for a few dozen generations. Would the result be the nineteenth century Plains pony as described by Europeans? Don't say it could be. Say whether you would expect that result. If the answer is no, then you can say 'it could be'. But at least admit you wouldn't assume it if you didn't already know it was 'true'.
Now do the same with the Australian horses. But this time, since we know for certain sure that the brumbeys are feral escapees, please tell us why they have produced a completely different horse though via a completely identical route. Although you have made great play about these weirdo Spanish breeds I just don't believe that these 'miniatures' and 'exotics' would either be common or likely to escape. Spanish and British colonists were remarkably similar when it comes to shifting horses halfway across the globe.
| And if you want to get onto the idea of linked descent, I do need to point out that they don't look anything like each other !!! |
Wha!? They're fookin' identical, that's the whole point. It's certainly the only point we agree with orthodoxy on. So, glad to see you're on your own on this one.
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Mick Harper
Site Admin
In: London
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You're just our whipping boy, Ishmael. Every group needs one.
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Ishmael
In: Toronto
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| berniegreen wrote: | | Sorry if this sounds all rather mundane and boring, but sometimes the truth is just like that. |
It doesn't sound boring. It sounds like rationalization.
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DPCrisp
In: Bedfordshire
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| ...bred for their appearance and temperament as riding horses. |
| I just don't believe that these 'miniatures' and 'exotics' would either be common or likely to escape. |
The most socially acclimatised horses, and the most closely kept, are the ones that ran away in droves?
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