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Posts Tagged ‘tame silver fox’

 

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.

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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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One of the hazards of breeding wild animals in captivity is that the forces of natural selection no longer act upon them. Specimens that thrive well enough of captivity are very often fundamentally quite different from those that would thrive in the wild. Those individuals who thrive well enough to reproduce may pass on traits that are entirely detrimental to living in the wild.

If the goal is to produce domesticated animals, as was the case in Belyaev’s fox farm experiment, one should rigorously select animals for tameness, docility, and general ease of handling.  Of course, when one does that, the animal fundamentally changes.

We have been doing that for thousands of years. We have become experts at selectively breeding domestic animals for any number of traits. We do not care that our Yorkshire pigs are nothing like Eurasian wild boars. We do not care that our Herefords and Holsteins are nothing like the extinct wild Aurochsen.  We are glad that our golden retrievers,  Scottish deerhounds, and Pekingeses are not exactly like wild wolves.

These domesticated animals fit their place in our society. They have a utility that is fundamentally different from their wild ancestors, and most of that utility comes from our skills at selecting desirable traits.

However, when our goal is to produce captive populations of wild animals that can be reintroduced into the wild, we often have problems. Simply put, we cannot create the conditions in captivity that imitate natural selection.

Try as we might, we simply cannot make it so that prey species evolve under predation. We cannot allow predators to hunt prey in captivity. If we are dealing with endangered animals, those activities are simply too risky to even try. Further, they most likely would violate  animal cruelty laws and could even violate conservation statutes. Endangered and threatened species are also too valuable for their genomes to ever experience possible risks of damaging or killing them. They must be treated as carefully as any museum artifact.

It is difficult to deny the reasoning behind such care. After all, every individual in a limited gene pool has importance, and we really shouldn’t be involved in what amount to canned hunts with endangered predators hunting endangered prey.

As noted earlier, once animals are removed from the pressures of natural selection, the animals themselves can evolve to  fit captivity.

Take the case of one line of the endangered Mexican wolf.

Mexican wolves (Canis lupus baileyi) are the smallest subspecies of wolf in North America. If the red wolf is a different species, it is generally believed to be the oldest extant subspecies in North America. It has unique markers in its mtDNA sequence that make it stand out from wolves from other populations on this continent. It was native to the Southwestern US and northern Mexico. It was extinct in the wild until 1998, when 11 individuals were released into the Blue Range in Arizona. Currently, about 50 Mexican wolves live wild in Arizona and adjacent New Mexico.

However, as a subspecies, it does have issues with compromised genetic diversity. Mexican and US ranchers nearly wiped the subspecies out.  The last of wild ones were all capture and then bred in captivity in hopes of preserving the subspecies.

One particular line of Mexican wolf was the Ghost Ranch colony. It was captured in New Mexico, and one of the founders of the line looked a bit like a wolf-dog. However, the rest all resembled wild Mexican wolves.

But as they bred over the generations, certain features began to pop up. Their heads got smaller. Their jaws got weaker. They were turning into dogs.

This line was bred at Carlsbad Caverns, and when it was decided to start breeding Mexican wolves with the possibility of releasing them into the wild, the status of the Ghost Ranch wolves fell into contention.

It is well-known that dogs and wolves will hybridize. In fact, it is probably not even correct to call wolf and dog crosses hybrids.  They are now recognized to be part of the same species, Canis lupus. It was suggested that Ghost Ranch wolves were derived from hybrid stock.

If that were true, then it meant that releasing wolves derived from that line could be contentious. The Endangered Species Act and state conservation laws were designed to protect Mexican wolves, not Mexican wolf and dog crosses. It would mean that a wolf haters could kill them and then claim that they were shooting a wolf hybrid, which is not a protected species at all.

Of course, that is not a trivial concern.

However, it was also suggested that the Ghost Ranch wolves were actually the result of a kind Belyaev experiment. Generations of being bred in captivity and being fed a less rigorous diet had changed these wolves in the same way the foxes were.

Because of the potential problems, the Ghost Ranch wolves were euthanized.  However, there are still a few individual wolves that are of the Ghost Ranch line. These animals are of great value.

You see, a later study of the DNA of Mexican wolves, including those of the Ghost Ranch line, found that there was no evidence of hybridization with dogs or coyotes. Not only were they free of that “contamination,” they were clearly genetically distinct from any wolf population in North America.

If only this sort of analysis had been performed before the majority of the Ghost Ranch wolves were euthanized, the Mexican wolf population would still have an important source of genetic diversity. Granted, they would probably would have those maladaptive doggish traits, but these possibly could have been bred out over time.

Also, there were some concerns that the McBride line, which is the main line that was used for reintroduction purposes, might have some issues with an inbreeding depression, and while there was no evidence of an inbreeding depression, it is known that it does have compromised genetic diversity. The Ghost Ranch and Aragon lines are also somewhat inbred, but it would make sense that allowing blood from these previously believed “unpure” lines would end some of these possible concerns.

However, there are very few Ghost Ranch wolves left. Twenty were found in the hands of a private owner, and these wolves were then added to the gene pool.

But because of the unintentional domestication of the Ghost Ranch wolves,  it was decided to get rid of this part of the gene pool.

Of course, when one is already dealing with a very rare subspecies, breeding practices can be loosened. Texas cougars were released to augment the Florida panther’s genetic diversity.  It is something that can be done, but it is generally frowned upon.

Releasing a wild animal that has possible domestic ancestry would always be a legal cheval-de-frise that wolf haters could use, so maybe euthanasia was a good idea at the time.

But all of this confusion could have been avoided if the wolves had been kept and bred to preserve as many wild characteristics as possible. This is not as easy as it sounds.

Although we are experts at selecting for tameness and docility in domestic animals, we are not so good at selecting for the traits that make animals survive well in the wild.

The best we can do is leave the animals alone in their enclosures and try not to put too many selective pressures for tameness on them.

However, the result of doing such a thing means that one is potentially producing dangerous animals that zoo staff cannot handle. In the clip about the foxes, the “wild” group that had been bred to retain those characteristics was far more aggressive. The “dragon” fox would probably have traits that would be good to have in the wild.

But those are just red foxes.

What if we are talking about Amur (Siberian) tigers?

Remember the San Francisco Zoo tiger that killed one person and maimed two others on Christmas Day in 2007?

That tiger had traits that would have made her survive well in the wild. Her aggressive behavior was strong enough that she could escape an enclosure that easily held other tigers.

Such an animal would be a liability in any facility, but her offspring might be well-adapted to eventually live in the wild. That is, if we ever figure out how to rewild captive tigers.

So in the end, we are left with a balancing act. The animals must be bred so they retain at least some of their instincts and physical traits. However, they cannot experience natural selection as their wild ancestors did. They have to be treated with care. They also have to be able to be contained in an enclosure, and they have to be tractable enough to be safe for staff to handle.

They also have to be able to breed in captivity, which is itself an important selective pressure. Not all individuals can reproduce in captivity. Male clouded leopards are often so aggressive that they kill their mates. To get clouded leopards to breed, males that are less aggressive toward their mates have to be used. That certainly will have an effect upon the behavior of their offspring. They may be less aggressive than typical wild male clouded leopards.

All of these things must be balanced in the light of maintaining a dynamic and diverse gene pool. Breeding animals that could eventually live in the wild is a much harder undertaking than breeding domesticated animals. We must balance lots of things with domestic animals, but with these wild animals, we also have to think as if we are imitating natural selection.

Not an easy task.

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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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