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Posted on 03/23/2009 1:53:09 PM PDT by LibWhacker
Sometimes we see things so often that we simply forget to ask “why are they like that?” For instance, let’s take a closer look at domestic animals. Dogs, cats, horses, cows, pigs - animals that we live with, and who couldn’t live without us.
What do all these domestic animals have in common?
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Now this isn’t a particularly subtle example, but that’s kind of the point. You can see that all of these domestic animals have large white patches - they’ve lost pigment in their coats in some areas. Why do we care? Well, this is something that is extremely common among domesticated animals, but very rare among wild animals. I hear you saying “but what about zebras, or any other wild animal with white patches?”. What we’re referring to here is slightly different. A zebra will always have that patterning, whereas what we’re looking at here is depigmentation - the loss of color in certain areas in an animal that is “normally” colored.
What else is common among domestic animals but rare in the wild? Well, things like dwarf and giant varieties, floppy ears, and non-seasonal mating. Charles Darwin, in Chapter One of Origin of the Species noted that “not a single domestic animal can be named which has not in some country drooping ears”. A very significant observation when you consider that there is only a single wild animal with drooping ears - the elephant.
So perhaps something weird is going on here. Why do animals as different as cats and dogs have these common traits? It seems to arise simply from being around humans!
The Russian geneticist Dmitri Belyaev provided a very interesting potential explanation. Genetics at the time was preoccupied with easily measurable traits that could be passed on - if you bred dogs, you could pick the biggest puppies, breed them, and they would produce bigger dogs on average. Fine. But that is selection of a single simple trait, something that likely did not require that many genes to “switch” in order for the puppies to be bigger.
But what if you were selecting for something more complicated? What if, instead of selecting for a simple trait like size or eye color, you selected for something more vague like behaviour - in this case, the very behaviour that made these animals more likely to be around humans. We can call it tamability, or lack of aggressiveness, or whatever - the point is, we are selecting for those animals who will behave in a manner we want around us. A wolf who does not display aggressive behaviour might be able to grab a few scraps of food from the garbage pile of a early human settlement, rather than being driven off.
And if we were selecting a complicated behaviour, rather than a simple trait, it seems likely that it will require more change in the animals genetic code. And since the genetic code is a tangled web where a small bit of DNA can be referenced in many areas of the body - perhaps selecting for a common behaviour would also cause other common traits to arise in animals that are otherwise different.
It’s like giving your car a paint job versus trying to make it go faster - the paint job is easy, but trying to make it faster could lead to your car exhibiting other traits you didn’t directly request, like consuming more gas during regular driving. This could be common across all your project cars. One is a low level trait (the paint, the size of puppy) that can be encompassed in a tiny bit of information (color, size), the other is a high level trait (speed, tamability) that must involve a wide variety of sub-systems changing as well.
Now if you were a Soviet scientist in the late 1950s, you probably worked on something awesome like a giant robot that shot nuclear missles, or a flying submarine. Not Dmitri Belyaev. No, he lost his job as head of the Department of Fur Animal Breeding at the Central Research Laboratory of Fur Breeding in Moscow in 1948 because he was committed to the theories of classical genetics rather than the very fashionable (and totally wrong) theories of Lysenkoism.
So instead, he started breeding foxes. Well, it was technically an experiment to study animal physiology, but that was more of a ruse to get his Lysenkoism-loving bosses off his back while he could study genetics and his theories of selecting for behaviour.
He started out with 130 silver foxes. Like foxes in the wild, their ears are erect, the tail is low slung, and the fur is silver-black with a white tip on the tail. Tameness was selected for rigorously - only about 5% of males and 20% of females were allowed to breed each generation.
At first, all foxes bred were classified as Class III foxes. They are tamer than the calmest farm-bred foxes, but flee from humans and will bite if stroked or handled.
The next generation of foxes were deemed Class II foxes. Class II foxes will allow humans to pet them and pick them up, but do not show any emotionally friendly response to people. If you are a cat owner, you would call the experiment a success at this point.
Later generations produced Class I foxes. They are eager to establish human contact, and will wag their tails and whine. Domesticated features were noted to occur with increasing frequency.
Forty years after the start of the experiment, 70 to 80 percent of the foxes are now Class IE - the “domesticated elite”. When raised with humans, they are affectionate devoted animals, capable of forming strong bonds with their owner.
These “elite” foxes also exhibit domestic features such as depigmentation (1,646% increase in frequency), floppy ears (35% increase in frequency), short tails (6,900% increase in frequency), and other traits also seen frequently in domesticated animals.
Belyaevn passed away in 1985, but he was able to witness the early success of his hypothesis, that selecting for behaviour can cause cascading changes throughout the entire organism. For instance, the current explanation for the loss of pigment is that melanin (a compound that acts to color the coat of the animal) shares a common pathway with adrenaline (a compound that increases the “fight or flight” instinct of an animal). Reduction of adrenaline (by selecting for tame animals) inadvertently reduces melanin (causing the observed depigmentation effects).
So if Belyaevn is right, genetics is not just a low slow process that works on tiny incremental tweaks. Complicated environmental pressures can result in complicated genetic results, in a stunningly quick period of time. Where do I think we’re going with this?
Well, designer pets for one. Following the collapse of the Soviet Union, the project ran into serious financial trouble in the late 1990s. They had to cut down the amount of foxes drastically, and the project survived primarily on funding obtained from selling the tame foxes as exotic pets. Imagine a menagerie of dwarf exotic animals, who crave human attention and form bonds with people. It would be obscenely profitable.
And the out there thought for the day? We’re doing this to ourselves. We don’t encourage people to act aggressively all day to everyone they meet. We reward certain behaviours more than other behaviours. My unprovable conjecture? Humanity is selecting itself for certain behaviours, and the traits we think of as fundamentally human (loss of hair, retention of juvenile characteristics relative to primates) are a side effect of this self-selection.
“Suddenly, it all started to make sense. As Belyaev bred his foxes for tameness, over the generations their bodies began producing different levels of a whole range of hormones. These hormones, in turn, set off a cascade of changes that somehow triggered a surprising degree of genetic variation.
Just the simple act of selecting for tameness destabilized the genetic make up of these animals in such a way that all sorts of stuff that you would never normally see in a wild population suddenly appeared.
His "out there" thought is not so far out there to conservatives who have been paying attention. Libs are gradually taming us, sissifying us. Soon there will be no one left capable of defending the country.
Bump
Domesticated Fox
http://www.youtube.com/watch?v=Lvzg0NplkLE
(Seriously, click it. You will the awwws in your heart)
Domesticated Fox
http://www.youtube.com/watch?v=Lvzg0NplkLE
(Seriously, click it. You will the awwws in your heart)
>Soon there will be no one left capable of defending the country.
*nod*
There’s the psychological aspect of it too...
I believe his theory.
The animal pictured is Vulpes ferengi but there is a movement among leftwing zoologists to rename it Vulpes obama
Cute, thanks! :-)
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I like the “and if you are a cat owner, at this point you would count the experiment as a success”.
Also the 1950’s Russian scientist working on a giant robot!
The Lysenko reference was nice also.
For those of you in Rio Linda, the Soviets opposed the theory of Evolution through natural selection of genetic variation as they thought of it as too capitalistic. They promoted a pseudo Lamarckian named Lysenko to oversee the new “communist science” of evolution that didn't involve natural selection or genes.
bump for later read. If this is the same Russian guy, than he’s making a correlation implying causation argument except that he doesn’t get the correlation right.
forced = forces. Libs are in teh internets, moving my letturz
Sorta like some peepole on FR?
Those peepoles.
That’s why when liberals start chanting ‘pacifism’, I always respond ‘no, it’s pacification so we will not resist an imperialist socialist world government.’ They always scatter like cockroaches when I say that.
There needs to be civil society, don’t me wrong. But we need aggressiveness at times too. Previous generations to the Baby Boomers understood that balance. Now that is being undone.
What the libs are really doing is pacifying the intelligent, educated, ambitious, patriotic people while agitating the uneducated, lazy, selfish people to violence, especially in the ghettos and trailer parks. Creating a two-tiered society where one is used to subdue the other and make the govt all-powerful in the process.
You haven't been in the 'hood lately. Its easy to breed when others pay the costs and give you a bonus, besides.
I somewhat disagree with your assessment. Many of the ‘fundamentally human’ traits such as prolonged adolescence and hair loss have been around for long before the whole liberal ‘peace’ movement came into being, or for that matter, centuries before America and our political parties even existed.
I think what he means by the part about not encouraging people to act aggressively doesn’t mean that we’re losing the ability or willingness to fight if necessary. Even in the case of a domesticated cat, you put him near another strange cat, and chances are the fur will start flying. Even in the cases of larger primates, like gorillas or chimps (remember that recent angry chimp story?) who live in social groups can get quite violent with outsiders, and the males will still fight each other like crazy. Humans, on the other hand, while they don’t feel the need to make friends with every single living thing like a domestic dog might, also don’t generally feel a drive to beat down or kill every stranger they meet like a wild animal would - and the few that do, we put into mental institutions.
Although, odd last thought about the prolonged adolescence, that’s certainly decresing these days, so if anything, it would indicate we’re getting more wired towards aggression as a general population. Although, it’s still all very fascinating.
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