| View previous topic :: View next topic |
DPCrisp
In: Bedfordshire
|
|
 |
|
| Unfortunately Dan, what was a simple and elegant hypothesis has now degenerated into what looks increasingly like special pleading. |
More waffling at this point, I would say, since we still only have the "common belief" -- we can put it no stronger than that -- that domesticates are smaller than their wild progenitors.
We don't have proper evidence of the correlation, or lack of one... but, of course, we are not going to get it simply by asking Orthodoxy: we need to take what they say about it with a pinch of salt: Paul Bunyan's pinch.
Still, it does seem a valid point to throw into the pot that manageability-by-humans is an important factor in the "societalisation" of animals.
Another valid is point is that some other "selection pressure" might favour the smaller among already-small animals in the unnatural conditions of captivity.
Dunno.
|
|
 |
|
 |
|
AJMorton
|
|
|
|
| Ishmael wrote: | | Can you guess where I am going? |
The Golden Ratio/Proportion by any chance?
(makes note to himself to look for Growth and Form)
|
|
| |
|
|
|
|
|
|
|
|
| Martin wrote: | | There are many feral horses around the world. But Przewalski's horse is the only wild horse and it is smaller than modern domesticated horses. Zebras, etc. are obviously related to the horse, but Przewalski's is related much more closely. So closely that if they are bred with a normal horse they can produce fertile offspring. |
But mules are occasionally fertile and can birth foals. This is the exact same way in which Przewalski's horse is fertile. If the Przewalski/horse hybrid is bred with a horse, you get a horse. If a mule is bred with a horse, you can get lucky and get a horse. Przewalski's horse (as previously mentioned) has 66 chromosomes, the horse 64, the donkey 62. So why not call a donkey a horse? It would seem we don't because it looks like a donkey. Why not call the onager (56 chromosomes) a wild horse instead a of wild donkey? Its head looks quite horse-like to me.
Anyway, the Przewalski's horse/horse and the donkey/onager distinction got me wondering. Apparently, the Przewalski horse and the onager are very difficult to tame. It makes me wonder what the wild was like a long time ago.
Was it populated by wild Przewalski's horses, horses, donkeys, and onagers? Then humans came along and domesticated the donkeys and horses, but not the Przewalski's horses and onagers because they weren't interested in being domesticated. Which would leave us with a scenario many years later where there were still wild Przewalski's horses and onagers, but no wild horses or donkeys.
Or were there no Przewalski's horses and onagers wandering around with the horses and donkeys a long time ago? In that case, the Przewalski's horses and onagers would have to be a by-product of horse breeding and donkey breeding.
There's some discussion here (albeit from the creationist camp) about how chromosomes can "break" and result in a new subspecies. http://www.asa3.org/archive/evolution/199807/0138.html
There's a donkey with white and black striped legs call Equus africanus somalicus. It, along with the horse and the donkey, are the only equid species to have been successfully domesticated. Here's an Egyptian burial from 5000 years ago of Equus africanus somalicus: http://www.foxnews.com/story/0,2933,336755,00.html
Chromosome analyses of Equus africanus somalicus have revealed that they have 62-64 chromosomes. http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowPDF&ProduktNr=224037&Ausgabe=225343&ArtikelNr=14966
|
|
| |
|
|
|
Komorikid
In: Gold Coast, Australia
|
|
|
|
There is a twin of the Przewalski horse and it is called the Fjord horse. It is virtually indistinguishable to the Przewalski right down to the unusual 'zebra like' striping on its flanks. However Fjord horses have 64 chromosomes and are therefore not considered a descendant of the Przewalski. This is strange to me. Two 'species' of horse that look the same in all respects that once shared the same physical environment and are discounted as related due to genetic theory that has been proven wrong ( if as you say 66 and 64 species can breed successfully).
There is something else that is gnawing at the back of my mind after reading about the Fjord horse. It has been around in Scandinavia for thousands of years and is very often found in Viking burials. Mick mentioned in another thread (Troy or Anglo-Saxon -- I can't remember just now) that 'boatie people' and 'horsey people' seem to be mutually exclusive. This appears not to be the case, which led me to the Normans.
I usually take Time Team evidence with a Bunyan size pinch but very very occasionally they manage to stumble and fall face first in a logical conclusion.Thus it was in a recent show about a Norman settlement. One of the 'guest boffins' happened to mention that all the graphic representations of Norman knights show them riding 'Small' horses as opposed to the modern (mainly movie derived) perception of the knight on his tall noble steed, whereupon they nipped of to the nearest Pony Club and borrowed a few kids' ponies (much to the horror of the kids, judging by the body language).
What ensued was a rather amusing 'drop the dead donkey' piece where said boffin in full Norman mail and armour mounted the pony and chased Phil Harding (dragging a sack) across the paddock. The 'knight' proceeded to spear the sack while giving chase to the Harding 'boar' or is that bore. I was hoping for the 'if it bleeds it leads' result. But alas it didn't happen.
Fjord horses are noted for their strength and resilience. Although pony like in stature they are incredibly strong for their size and one of the few horses in the world able to handle rough terrain. They also don't need to be shod as their hooves are much stronger than those of other equines. They can easily be ridden by an adult Northman even one in full battle dress as attested in Arabic scripts.
Anyway the Normans are said to be Scandinavians who settled in France at a time undetermined. Could it be that they are the same people Strabo and Caesar spoke of who were plying the western Atlantic coast in longboats long before the 1st century AD. Sailors who were also horsemen seem to be a north Atlantic coast phenomenon; Normans, Vikings, Celts and Homer's combatants.
|
|
| |
|
|
|
Tatjana
In: exiled in Germany
|
|
|
|
I might be a bit late here, but I just followed the thread from the old days up to to-day, and as you mention Fjordies...
I had one when at Uni, a pure-bred Norwegian Fjord Horse as they are officially named, and he was just about the greatest - although only 14 hands shoulder-height, he had no probs whatsoever carrying really big guys even at a gallop uphill - yes, they are strong!Strong, but kind-natured and gentle, I took him for teaching horse-riding to six-year-olds... but I didn't want to go down memory lane.
I was going to say - and this leads to the maritime connections between the coastal regions of megalithic Europe! - that the Fjord horse apparently has been bred by crossing horses from Ireland, i.e. what later became the Connemara Pony with indigenous Scandinavian horses (maybe a Prezwalksy variety - ye gods I never spell that right!). It was believed that the Vikings brought original Connies to Norway and crossed them with their own - but that can't be quite right, since the Fjordies are found earlier than Viking times... so who brought the Irish Horses to Scandinavia??
BTW : Connemara Ponies show sometimes the same features as Fjordies, i.e. eel stripe and zebra stripes on the legs, as well as the distinctive dun colour of the Fjordy and Prez-you know what horse!! I know because I had fifty Connies to take care of at a Connemara Pony stud in Connemara Heart land. And the local breeders told me that "it's a fall-back to the ancient looks".
So there!
_________________
-Gory at thasp, keener fortha karabd-
|
|
| |
|
|
|
|
|
|
|
|
| Mick Harper wrote: | 1. Every time I read about domestication, it was stated that the domesticate was smaller than the wild version.
|
Apparently human faces are getting smaller. The Times says our faces have shrunk about 30% since the advent of farming: 'Many men [some time ago] would have had the shape of Arnold Schwarzenegger's head while women might have looked more like Camilla [the Duchess of Cornwall]. By contrast, Tony Blair and George Bush are good examples of the more delicate modern form.'
http://www.timesonline.co.uk/tol/news/uk/article592250.ece
Chris Stringer also says we're shrinking: "Research from several continents reveals that the human race has been waning anatomically for the past ten millennia. Men today are about 5 ft 8 to 5 ft 9 in tall in the West. Cro-Magnon males were about 6 ft. Even our brains have been getting smaller than those of Cro-Magnons...[the middle ages in which soldiers wore small suits of armour are a blip due to poor nutrition during the middle ages]...the real underlying trend is one of decreasing stature."
Furthermore, this shrinkage "was accentuated by farming, which began about 10,000 years ago...[farming] lessened the need for robust physiques and we have been shrinking ever since."
However, some researchers don't buy the farming = shrinking hypothesis, because farming didn't arrive in Australia until 200 years ago. "Ten thousand years ago, aborigine men were between 5 ft 9 in and 6 ft tall. Today they are between 5 ft 5 in and 5 ft 6. More to the point, humans were not the only species which shrank. In Australia, every animal bigger than a wombat got smaller." The standard answer to why both hunter and prey have gotten smaller is climate change.
However, Majie Henneberg of Adelaide University offers a different answer than climate change. He studied birth records and noted that children born between May and October are 11% lighter than those born the rest of the year. Similar fluctuations are observed with dogs. "This is probably related to the position of our planet on its elliptical orbit," says Henneberg. Gravity and electromagnetism vary, and probably produce those annual changes in human and dog size, as well as in other animals, he argues. And if minor stature-changing fluctuations in radiation and growth occur round the year, then there may be far bigger alterations taking place over several millennia, ones that may be responsible for those drops in human size.
|
|
| |
|
|
|
Hatty
Site Admin
In: Berkshire
|
|
|
|
| the middle ages in which soldiers wore small suits of armour are a blip due to poor nutrition during the middle ages ... |
I'm a bit uneasy about ascribing small stature to "poor nutrition during the Middle Ages", such a sweeping conclusion must mean they can't explain it surely. Steve Jones was talking about Lysenko, Stalin's fanatical but inept geneticist, and admitted he (Jones that is) was furious because it seems Lysenko wasn't entirely wrong and environmental factors do affect things like growth thanks to a Swedish example where the grandparents living in a time of famine produced 'normal' sons but their sons' offspring had mutated somewhat in order to cope with famine conditions. (Have you ever come across a mother whose sons are smaller than her?)
|
|
| |
|
|
|
Mick Harper
Site Admin
In: London
|
|
|
|
Wow! That's big news that dear ol' Lysenko is getting a place in the sun. What price full-blown Lamarckism? I am occasionally in conversation with Steve Jones about The Name That Ancestor challenge in THOBR.
PS Professor Jones of course is approaching Grand Old Man status which, Applied Epistemology points out, is the only time someone on the inside is allowed to make heretical statements. So maybe his observations are not significant after all.
|
|
| |
|
|
|
DPCrisp
In: Bedfordshire
|
|
|
|
| Or were there no Przewalski's horses and onagers wandering around with the horses and donkeys a long time ago? In that case, the Przewalski's horses and onagers would have to be a by-product of horse breeding and donkey breeding. |
That's more like it, since
a) domestic animals are a subset, one branch of the wild family, as shown in their narrow genetic diversity (an oxymoron). They have to resort to genetic gymnastics to explain the domestic horses' similarity to "wild" horses, which are all rather "coverse" compared to specimens of 10/12k years ago. The simple answer is that wild horses are extinct and all horses/ponies are domesticated or feral. No one has studied their genetics in the light of feral horses having an awful long time to get up to their own shenanigans.
b) the absence of wild horses suggests they were rather deliberately exterminated.
| Chromosome analyses of Equus africanus somalicus have revealed that they have 62-64 chromosomes. |
So much for a definition of species based on chromosomes.
|
|
| |
|
|
|
DPCrisp
In: Bedfordshire
|
|
|
|
| Sailors who were also horsemen seem to be a north Atlantic coast phenomenon; Normans, Vikings, Celts and Homer's combatants. |
Remember: Poseidon is the Tamer of Horses.
|
|
| |
|
|
|
DPCrisp
In: Bedfordshire
|
|
|
|
| "Research from several continents reveals that the human race has been waning anatomically for the past ten millennia. Men today are about 5 ft 8 to 5 ft 9 in tall in the West. Cro-Magnon males were about 6 ft. Even our brains have been getting smaller than those of Cro-Magnons..." |
If we're not careful, someone will mention the proposed connection between Cro-Magnon and Atlantis and the gradual degeneracy from their god-like forebears. Another thing that Plato knew but wasn't supposed to?
| "[farming] lessened the need for robust physiques and we have been shrinking ever since." |
Farming increases the supply of bullshit.
| "He studied birth records and noted that children born between May and October are 11% lighter than those born the rest of the year... Gravity and electromagnetism vary, and probably produce those annual changes in human and dog size... there may be far bigger alterations taking place over several millennia" |
Isn't it more likely to have something to do with summer heat during that last month of fast development? (Less likely to have something to do with winter cold at conception, but who knows?)
Is there a trend towards summer births that would compound the shrinkage?
| I'm a bit uneasy about ascribing small stature to "poor nutrition during the Middle Ages", such a sweeping conclusion must mean they can't explain it surely. |
Poor nutrition among the armour-wearing class...?
How does in-breeding sound?
|
|
| |
|
|
|
Hatty
Site Admin
In: Berkshire
|
|
|
|
Poor nutrition among the armour-wearing class...?
How does in-breeding sound? |
In the Medieval Season Michael Woods mentioned that the 14th century 'Christina' was chronically under-nourished...she came from a relatively disadvantaged class but would armour-wearing people have any more access to or knowledge of nutrition? (He didn't say she was under-sized though. Some of the bones they'd exhumed showed the effects of hard work on health/longevity but I don't remember diet being responsible for skeletal underdevelopment).
| Is there a trend towards summer births that would compound the shrinkage? |
The headmistress of my sons' primary school said the children born after September "never catch up"; she was referring of course to the way the school year is structured and the autumn intake but I wonder...every child should "catch up" by the time they get to GCSE stage.
| The simple answer is that wild horses are extinct and all horses/ponies are domesticated or feral. |
There was an episode in the 'Wild China' series a couple of weeks ago where "wild" Mongolian ponies were segregated until the caravanserai of "domesticated" ponies and cattle had passed by, ostensibly to prevent breeding, or contamination, between the species which of course looked exactly the same. The result: the "wild" ponies were let loose after the other lot had gone and eaten all the best pasture. Easy to see why the numbers of so-called wild herds might decline.
|
|
| |
|
|
|
Mick Harper
Site Admin
In: London
|
|
|
|
I think an opposite assumption is called for. There are at least two excellent reasons for the wild horses to be extinguished -- miscegenation with the domesticates and competition for grazing -- yet after all these years (hundreds? thousands?) these wild horses still apparently flourish.
My guess is that these are feral animals that are permitted to exist (either consciously or by immemorial custom) for sound genetic reasons ie in case inbreeding within the domesticates leads to long-term problems.
|
|
| |
|
|
|
DPCrisp
In: Bedfordshire
|
|
|
|
| would armour-wearing people have any more access to or knowledge of nutrition? |
That's a tough call: I'm not sure that we know what we're talking about now. It is possible, especially at the richer end of the spectrum, for fashion to make malnutrition endemic... Is anyone collating the results from the Supersizers series?
| Some of the bones they'd exhumed showed the effects of hard work on health/longevity but I don't remember diet being responsible for skeletal underdevelopment. |
Yeah, you also get those lines in tooth enamel and long bones that say are caused by bouts of malnutrition (or illness), but I don't recall stunted growth being commented on, let alone explained as the result of malnutrition.
|
|
| |
|
|
|
DPCrisp
In: Bedfordshire
|
|
|
|
| ...competition for grazing -- yet after all these years (hundreds? thousands?) these wild horses still apparently flourish. |
In Mongolia we're talking about a crappy environment aren't we, where nomadic pastoralism is the only way to eke a living? You'd think no competition would be supported/tolerated. But if the "wild" horses were penned, they can't have been all that wild.
| My guess is that these are feral animals that are permitted to exist (either consciously or by immemorial custom) for sound genetic reasons ie in case inbreeding within the domesticates leads to long-term problems. |
Sounds, good: as though the Europeans had noticed in time that their cattle were not hardy enough for the Great Plains and left some bison to draw on... if you see what I mean.
|
|
| |
|
|
|
|
The Library Index 
FAQ 
Search
Register
Profile 
Log in to check your private messages 
Log in 
