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Posts Tagged ‘Dmitri Belyaev’

The following foxes have nothing to do with Dmitri Belyaev Siberian fox farm experiment:

Pearl foxes. Marked like border collies but not selected for tameness.

Irish marked marble fox, full body view.

Marbled fox. Almost entirely white.

Another marbled fox. These foxes are sometimes sold to rubes as arctic foxes. They are nothing more than red foxes with unusual coat colors. Arctic foxes are white only in winter. These foxes are always predominantly white.

These phases not result from their ancestors being systematically selected for flight distance or decreased aggression towards humans.

They resulted simply from unusual sports that popped up in farm fox breeding operations, and then the owners began to select for these color varieties. They normally aren’t uniform enough to make good pelts, but they often sold to roadside zoos.

These colors probably popped up as a consequence of being bred in captivity.  Belyaev suggested that his team was actually selecting for for genes that affect neurotransmitters that also affect melanin production.  So in this hypothesis, the selection for “tameness” increased the likelihood of producing spots.  But captivity produces a series of selection pressures on wild species that might be connected to selecting for both neurotransmitters and spots. It’s not tameness as defined by this experiment that affects morphology. It  is simply being bred in captivity that produced the spots.

Again, we actually don’t know the exact genetic basis behind the spotting, but we do know that these are phases that have been selected for in captivity.

Mark Derr in How the Dog Became the Dog points out that the control population of foxes in the Belyaev experiment also produced these spotted forms.  It was not the selection for tameness or docility that produced the spots.

The truth is we just don’t know why they are spotted.  The neurotransmitter-melanin hypothesis is worth exploring.

However, wild animals have been born with spots.

As I mentioned earlier, the leopard complex in horses existed when horses were wild animals. There were “Appaloosa” horses 25,000 years ago. People were hunting horses in those days. They weren’t selecting them to be tame at all.

There are also piebald white-tailed deer.  They are rare, but they are just as wild as the ones without spots.

It is possible that spotting is less of a problem for large ungulates in the wild than it would be for predatory mammals, even among those– such as wolves and foxes– that don’t use their coloration as camouflage.  Animals with lots of spots would have a hard time hunting for whatever reason, and nature would strongly select against these colors.

However  it may be that spotting is of no consequence with certain species of ungulate.

Of course, there is research that shows that most ungulates are uniform in color because predators tend to select those that are aberrant. That’s why you don’t often see white gnus or dalmatian-spotted gazelles.

The truth is we simply don’t know why some animals develop spotted pelts.

We have many hypotheses.

But the truth is likely quite complex.

And artificial selection is too often ignored as an agency.

The fox farm experiment likes to make a lot of hay out of the coat color changes in the domesticated foxes, but it doesn’t answer why marbled and pearl foxes turned up in populations that were never selected for tameness in this fashion.

We are simply not served well by such reductionism.

 

 

 

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Kent Hovind misuses the Belyaev fox farm experiment to claim that all the dogs, both wild and domestic, came from two of the "dog kind" that were on the ark.

 

 

Boy, this is a good one!

First, let’s look at some facts regarding dogs. Most experts say there are about 400± recognized breeds of dogs in the world today. Most also agree that they are all interfertile (can produce puppies) and are therefore the same “kind” of animal. Ten times in Genesis chapter one, God said the plants and animals would bring forth after their “kind,” not their species.

The use of the word “species” sometimes clouds our communication, as there has never been an airtight definition of the word “species.” Darwin’s book entitled, On the Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life never does tell us about the ORIGIN of species at all. He only covered his unproven ideas on how he thinks species might have changed over the “millions of years” he claimed that the world has possibly been here.

It is true that there are a wide variety of dogs on earth today but please consider the following list of facts. Yes, my mind works best from lists. :

All the evidence that mankind has ever been able to observe shows us that dogs produce dogs.

While there are small dogs and large dogs, there seems to be a limit. I would be willing to bet no one will never get a dog as small as a flea or as big as Texas.

Dogs also seem able to “adapt” to various climates. Some can survive at -30F in Alaska and others have “adapted” to ±120 in deserts. Again however, there are limits. They will never adapt to ±300F! Or 10,000F!!!

I have had several people who raise dogs for a living tell me that they can take fifty generic “mutts” from the dog pound and, with selective breeding, re-create nearly every breed of dog today in less than 100 years.

Richard Dawkins, famous English atheist who hates creationists (See the movie, “Expelled”. You can purchase it by clicking here), wrote a book in 2005 called The Ancestor’s Tale. On pages 29-31, he tells of a Russian science team that took captive silver foxes and bred them for “tameness.” In twenty years, they watched them change into dogs! They looked like border collies, sought human company, wagged their tails when approached, had black and white coats, had dog-like muzzles and “lovable” floppy ears, developed hormone changes to breed year round, and displayed less aggression. I think you will find that nearly everyone (creationist or evolutionist) agrees that all dogs could have descended from foxes or wolves with no problems.

To look at the really big picture, I think it is funny to listen to an evolutionists ask a creationist, “How could all the dogs in the world come from just two dogs on Noah’s ark?” and then turn around and teach that all the dogs in the world came from a rock! Over billions of years of course! (Or quickly if you are from Harvard!) On page 31 of The Ancestor’s Tale, Dawkins says, “It is entirely probable that cattle, pigs horses, sheep, goats, chickens, geese, ducks, and camels followed a course which was just as fast and just as rich in unexpected side-effects.”

Keep in mind that the changes needed to turn a wolf, fox, or jackal into a dog are minor compared to turning a rock into a dog or even an amoeba into a dog. I’m even willing to let them have the huge head start of not dealing with the major problem of the origin of life issue and letting them start with a hamster (already a mammal, air-breathing, and land-dwelling) and see if they can turn it into a dog.

Don’t be thrown off track by those who question God’s Word with their detail questions about Noah’s ark. I think there are plenty of great answers to nearly all the questions the atheists raise and I cover many of them in the Creation Seminar. For the questions for which we don’t have answers yet, keep seeking for truth and God will provide the answers as we go and as we need them.

***

Of course, he makes no mention of what that dog kind was. We all know from credible creationist sources that this “dog kind” was the Afghan hound. That means that all dogs from gray foxes to bulldogs to maned wolves descend from that animal. Of course, that would that mutations occur within populations at a startling rate to create such amazing genetic and morphological variation.

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Hovind is right that the term species is very nebulous. I don’t consider domestic dogs to be a separate species from wolves, and I am skeptical that the red wolf and the Eastern timber wolf are separate species from the rest.

That said, I don’t think foxes are the same species as wolves. I don’t think dogs descend from foxes. I don’t know of a single person with any kind of credibility who thinks so. (No. Chihuahuas are not derived from fennec foxes!)

However, Kent thinks that’s a possibility because of the Belyaev experiment. He thinks that they actually created dogs (as in the same species as domestic dogs) through selecting for tameness alone. Yes. They look like border collies, but they are not border collies. They are genetically tame red foxes of the silver phase. This study is used as an analogy to see how domestication might have worked in domestic dogs in their evolution from wild wolves.

Hovind is correct that you could take a large population of randomly-bred dogs and, through an intense selective process, produce something like all the dog breeds we have today. That’s actually what happened in the past 150 years. The many generic and specialist working-type landraces were selected and “improved” into many different breeds. That happens because dogs are very susceptible to selective breeding. Although no one has bred one the size of a flea or the size of a Texas, but we have produced 20o-plus pound English mastiffs and chihuahuas that weigh less than two pounds. This diversity is reflected in the wild Canis lupus species, which once existed in such diverse forms as the 25-pound Honshu wolf to the giant Pleistocene wolf of Alaska with bone crushing jaws.

One of the reasons why dogs and wolves vary so much in appearance is just a little variation on a few genes have great effects upon phenotype. Just slight variations on one gene produces the great variance in size in domestic dogs. In addition, their DNA has an unusually high number of tandem repeats, which also means that they can rapidly evolve diverse phenotypes.

But if Hovind thinks the whole 35ish species in the dog family are derived from just two individuals of the “dog kind,” he must believe in super evolution. While it is true that golden jackals, coyotes, and Ethiopian wolves can crossbreed with both wild and domestic Canis lupus, fertility issues exist when dog/coyote and dog/golden jackal hybrids are bred to each other over the generations. These fertility issues strongly suggest that golden jackals and coyotes are distinct species, despite the fact that many of these hybrids are fertile.  Although there is some anecdotal evidence that a crab-eating fox (which is a South American wild dog, a close relative of the genus Canis) crossed with a domestic dog, there have been no verified dog and fox hybrids. The dhole and painted wolf/African wild dog (Lycaon pictus) cannot hybridize with the members of the genus Canis, and no verified hybrids exist between black-backed jackals and side-striped jackals and other members of the genus Canis.

These animals cannot interbreed because they vary too much genetically.

How could all of this variation result from two dogs (which we all know were Afghan hounds) that were on the ark? We all know that breeding from two dogs in such a fashion would produce animals that have very little genetic diversity. They likely wouldn’t be able to reproduce after just a few generations of breeding from such close relatives.

Hovind totally misunderstands the literature on the dog family. Yes. The Belyaev experiment is very useful in seeing how the domestication process alone might have created all the interesting phases and types that occur in domestic animals.

The silver-phase red foxes in this experiment did become dog-like. They were still red foxes. They did not become dogs.

Would you take tax advice from someone like this?

 

 

 

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Source.

Remember that oft-repeated story about the Soviet silver fox experiment?

Every time I mention it, I get a query about where you can get one.

When I first started writing about them, I found that they weren’t exporting them to the United States. They were offered for sale as pets, but there were fears that they would become a mass-produced fad pet– like African hybrid hedgehogs and pot bellied pigs.

Well, now there is a company that is offering them for sale in this country.

I won’t be getting one for two simple reasons.

1. They are a bit costly: $5,950.

2. I live in a state that refuses to offer any permits for pet red foxes. We have had a rabies outbreak in the southeastern part of the state, so the DNR no longer offers permits for pet red or gray foxes, raccoons, or skunks.

So if you want a pet fox in West Virginia, you better get a Pomeranian.

Just not the Pomeranian that this Chinese man purchased.

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