[ SHOWGSD-L ] Re: Genetics and unforseen results
- From: Stormy Hope <stormy435@xxxxxxxxx>
- To: MORGAN LEWIS <shadowland22000@xxxxxxxxx>, GSD List <showgsd-l@xxxxxxxxxxxxx>
- Date: Tue, 17 Jan 2012 18:13:38 -0800
That's a great study and one that has been the hallmark for other
studies on the effect of domestication on various wildlife forms.
Stormy Hope
On Jan 17, 2012, at 5:27 PM, MORGAN LEWIS wrote:
Early Canid Domestication:
The Farm Fox Experiment
Foxes bred for tameability in a 40-year experiment exhibit remarkable
transformations that suggest an interplay between behavioral genetics
and development.
When scientists ponder how animals came to be domesticated, they
almost inevitably wind up thinking about dogs. The dog was probably
the first domestic animal, and it is the one in which domestication
has progressed the furthest - far enough to turn Canis lupus into
Canis familiaris.
Evolutionary theorists have long speculated about exactly how dogs'
association with human beings may have been linked to their divergence
from their wild wolf forebears, a topic that anthropologist Darcy
Morey has discussed in some detail in the pages of this magazine,
(July-August, 1994). As Morey pointed out, debates about the origins
of animal domestication tend to focus on "the issue of intentionality"
- the extent to which domestication was the result of deliberate human
choice. Was domestication actually "self-domestication," the
colonization of new ecological niches by animals such as wolves? Or
did it result from intentional decisions by human beings? How you
answer those questions will determine how you understand the
morphological and physiological changes that domestication has brought
about-whether as the results of the pressure of natural selection in a
new niche, or as deliberately cultivated advantageous traits.
In many ways, though, the question of intentionality is beside the
point. Domestication was not a single event but rather a long, complex
process. Natural selection and artificial selection may both have
operated at different times or even at the same time. For example,
even if prehistoric people deliberately set out to domesticate wolves,
natural selection would still have been at work. The selective regime
may have changed drastically when wolves started living with people,
but selective pressure continued regardless of anything Homo sapiens
chose to do.
Another problem with the debate over intentionality is that it can
overshadow other important questions. For example, in becoming
domesticated, animals have undergone a host of changes in morphology,
physiology and behavior. What do those changes have in common?
Do they stem from a single cause, and if so, what is it? In the case
of the dog, Morey identifies one common factor as pedomorphosis,the
retention of juvenile traits by adults. Those traits include both
morphological ones, such as skulls that are unusually broad for their
length, and behavioral ones, such as whining, barking and
submissiveness - all characteristics that wolves outgrow but that dogs
do not. Morey considers pedomorphosis in dogs a byproduct of natural
selection for earlier sexual maturity and smaller body size, features
that, according to evolutionary theory, ought to increase the fitness
of animals engaged in colonizing a new ecological niche.
The common patterns are not confined to a single species. In a wide
range of mammals - herbivores and predators, large and small -
domestication seems to have brought with it strikingly similar changes
in appearance and behavior: changes in size, changes in coat color,
even changes in the animals' reproductive cycles. Our research group
at the Institute of Cytology and Genetics in Novosibirsk, Siberia, has
spent decades investigating such patterns and other questions of the
early evolution of domestic animals. Our work grew out of the
interests and ideas of the late director of our institute, the
geneticist Dmitry K. Belyaev.
Like Morey, Belyaev believed that the pattems of changes observed in
domesticated animals resulted from genetic changes that occurred in
the course of selection. Belyaev, however, believed that the key
factor selected for was not size or reproduction, but behavior;
specifically amenability to domestication, or tamability. More than
any other quality, Belyaev believed, tamability must have determined
how well an animal would adapt to life among human beings. Because
behavior is rooted in biology, selecting for tameness and against
aggression means selecting for physiological changes in the systems
that govem the body's hormones and neurochemicals. Those changes, in
turn, could have had far-reaching effects on the development of the
animals themselves, effects that might well explain why different
animals would respond in similar ways when subjected to the same kinds
of selective pressures.
To test his hypothesis, Belyaev decided to turn back the clock to the
point at which animals received the first challenge of domestication.
By replaying the process, he would be able to see how changes in
behavior, physiology and morphology first came about. Of course,
reproducing the ways and means of those ancient transformations, even
in the roughest outlines, would be a formidable task. To keep things
as clear and simple as possible, Belyaev designed a selective-breeding
program to reproduce a single major factor, a strong selection
pressure for tamability. He chose as his experimental model a species
taxonomically close to the dog but never before domesticated: Vulpes
vulpes, the silver fox. Belyaev's fox-breeding experiment occupied the
last 26 years of his life.
Today, 14 years after his death, it is still in progress. Through
genetic selection alone, our research group has created a population
of tame foxes fundamentally different in temperament and behavior from
their wild forebears. In the process we have observed some striking
changes in physiology, morphology and behavior, which mirror the
changes known in other domestic animals and bear out many of Belyaev's
ideas.
Belyaev's Hypothesis
Belyaev began his experiment in 1959, a time when Soviet genetics was
starting to recover from the anti-Darwinian ideology of Trofim
Lysenko. Belyaev's own career had suffered. In 1948, his commitment to
orthodox genetics had cost him his job as head of the Department of
Fur Animal Breeding at the Central Research Laboratory of Fur Breeding
in Moscow. During the 1950s he continued to conduct genetic research
under the guise of studying animal physiology. He moved to
Novosibirsk, where he helped found the Siberian Department of the
Soviet (now Russian) Academy of Sciences and became the director of
the Department's Institute of Cytology and Genetics, a post he held
from 1959 until his death in 1985. Under his leadership the institute
became a center of basic and applied research in both classical
genetics and modern molecular genetics. His own work included ground-
breaking investigations of evolutionary change in animals under
extreme conditions
(including domestication) and of the evolutionary roles of factors
such as stress, selection for behavioral traits and the environmental
photoperiod, or duration of natural daylight. Animal domestication was
his lifelong project, and fur bearers were his favorite subjects.
Early in the process of domestication, Belyaev noted, most domestic
animals had undergone the same basic morphological and physiological
changes. Their bodies changed in size and proportions, leading to the
appearance of dwarf and giant breeds. The normal pattern of coat color
that had evolved as camouflage in the wild altered as well. Many
domesticated animals are piebald, completely lacking pigmentation in
specific body areas. Hair turned wavy or curly, as it has done in
Astrakhan sheep, poodles, domestic donkeys, horses, pigs, goats and
even laboratory mice and guinea pigs. Some animals' hair also became
longer (Angora type) or shorter (rex type).
Tails changed, too. Many breeds of dogs and pigs carry their tails
curled up in a circle or semicircle. Some dogs, cats and sheep have
short tails resulting from a decrease in the number of tail vertebrae.
Ears became floppy. As Darwin noted in chapter 1 of On the Origin of
Species, "not a single domestic animal can be named which has not in
some country drooping ears" - a feature not found in any wild animal
except the elephant.
Another major evolutionary consequence of domestication is loss of the
seasonal rhythm of reproduction. Most wild animals in middle latitudes
are genetically programmed to mate once a year, during mating seasons
cued by changes in daylight. Domestic animals at the same latitudes,
however, now can mate and bear young more than once a year and in any
season.
Belyaev believed that similarity in the patterns of these traits was
the result of selection for amenability to domestication. Behavioral
responses, he reasoned, are regulated by a fine balance between
neurotransmitters and hormones at the level of the whole organism. The
genes that control that balance occupy a high level in the
hierarchical system of the genome. Even slight alterations in those
regulatory genes can give rise to a wide network of changes in the
developmental processes they govern. Thus, selecting animals for
behavior may lead to other, far-reaching changes in the animals'
development. Because mammals from widely different taxonomic groups
share similar regulatory mechanisms for hormones and neurochemistry,
it is reasonable to believe that selecting them for similar behavior -
tameness - should alter those mechanisms, and the developmental
pathways they govern, in similar ways.
For Belyaev's hypothesis to make evolutionary sense, two more things
must be true. Variations in tamability must be determined at least
partly by an animal's genes, and domestication must place that animal
under strong selective pressure. We have looked into both questions.
In the early 1960s our team studied the patterns and nature of
tamability in populations of farm foxes. We cross-bred foxes of
different behavior, cross-fostered newborns and even transplanted
embryos between donor and host mothers known to react differently to
human beings. Our studies showed that about 35 percent of the
variations in the foxes' defense response to the experimenter are
genetically determined. To get some idea of how powerful the selective
pressures on those genes might have been, our group has domesticated
other animals, including river otters (Lutra lutra) and gray rats
(Rattus norvegicus) caught in the wild. Out of 50 otters caught during
recent years, only eight
of them (16 percent) showing weak defensive behavior made a genetic
contribution to the next generation. Among the gray rats, only 14
percent of the wild-caught yielded offspring living to adulthood. If
our numbers are typical, it is clear that domestication must place
wild animals under extreme stress and severe selective pressure.
The Experiment
In setting up our breeding experiment, Belyaev bypassed that initial
trauma. He began with 30 male foxes and 100 vixens, most of them from
a commercial fur farm in Estonia. The founding foxes were already
tamer than their wild relatives. Foxes had been farmed since the
beginning of this century, so the earliest steps of domestication-
capture, caging and isolation from other wild foxes-had already left
their marks on our foxes' genes and behavior.
From the outset, Belyaev selected foxes for tameness and tameness
alone, a criterion we have scrupulously followed. Selection is
strict;in recent years, typically not more than 4 or 5 percent of male
offspring and about 20 percent of female offspring have been allowed
to breed.
To ensure that their tameness results from genetic selection, we do
not train the foxes. Most of them spend their lives in cages and are
allowed only brief "time dosed" contacts with human beings. Pups are
caged with their mothers until they are I/2 to 2 months old. Then they
are caged with their litter mates but without their mothers. At three
months, each pup is moved to its own cage.
To evaluate the foxes for tameness, we give them a series of tests.
When a pup is one month old, an experimenter offers it food from his
hand while trying to stroke and handle the pup. The pups are tested
twice, once in a cage and once while moving freely with other pups in
an enclosure, where they can choose to make contact either with the
human experimenter or with another pup. The test is repeated monthly
until the pups are six or seven months old.
At seven or eight months, when the foxes reach sexual maturity, they
are scored for tameness and assigned to one of three classes. The
least domesticated foxes, those that flee from experimenters or bite
when stroked or handled, are assigned to Class III. (Even Class III
foxes are tamer than the calmest farm-bred foxes. Among other things,
they allow themselves to be hand fed.) Foxes in Class II let
themselves be petted and handled but show no emotionally friendly
response to experimenters. Foxes in Class I are friendly toward
experimenters, wagging their tails and whining. In the sixth
generation bred for tameness we had to add an even higher-scoring
category. Members of Class IE, the "domesticated elite," are eager to
establish human contact, whimpering to attract attention and sniffing
and licking experimenters like dogs. They start displaying this kind
of behavior before they are one month old. By the tenth generation, 18
percent of fox pups were
elite; by the 20th, the figure had reached 35 percent. Today elite
foxes make up 70 to 80 percent of our experimentally selected
population.
Now, 40 years and 45,000 foxes after Belyaev began, our experiment has
achieved an array of concrete results. The most obvious of them is a
unique population of 100 foxes (at latest count), each of them the
product of between 30 and 35 generations of selection. They are
unusual animals, docile, eager to please and unmistakably
domesticated. When tested in groups in an enclosure, pups compete for
attention, snarling fiercely at one another as they seek the favor of
their human handler. Over the years several of our domesticated foxes
have escaped from the fur farm for days. All of them eventually
returned. Probably they would have been unable to survive in the wild.
Physical Changes
Physically, the foxes differ markedly from their wild relatives. Some
of the differences have obvious links to the changes in their social
behavior. In dogs, for example, it is well known that the first weeks
of life are crucial for forming primary social bonds with human
beings. The "window" of bonding opens when a puppy becomes able to
sense and explore its surroundings, and it closes when the pup starts
to fear unknown stimuli.
According to our studies, nondomesticated fox pups start responding to
auditory stimuli on day 16 after birth, and their eyes are completely
open by day 18 or 19. On average, our domesticated fox pups respond to
sounds two days earlier and open their eyes a day earlier than their
nondomesticated cousins. Nondomesticated foxes first show the fear
response at 6 weeks of age; domesticated ones show it after 9 weeks or
even later. (Dogs show it at 8 to 12 weeks, depending on the breed.)
As a result, domesticated pups have more time to become incorporated
into a human social environment.
Moreover, we have found that the delayed development of the fear
response is linked to changes in plasma levels of corticosteroids,
hormones concerned with an animal's adaptation to stress. In foxes,
the level of corticosteroids rises sharply between the ages of 2 to 4
months and reach adult levels by the age of 8 months. One of our
studies found that the more advanced an animal's selection for
domesticated behavior was, the later it showed the fear response and
the later came the surge in its plasma corticosteroids. Thus,
selection for domestication gives rises to changes in the timing of
the postnatal development of certain physiological and hormonal
mechanisms underlying the formation of social behavior.
Other physical changes mirror those in dogs and other domesticated
animals. In our foxes, novel traits began to appear in the eighth to
tenth selected generations. The first ones we noted were changes in
the foxes' coat color, chiefly a loss of pigment in certain areas of
the body, leading in some cases to a star-shaped pattern on the face
similar to that seen in some breeds of dog. Next came traits such as
floppy ears and rolled tails similar to those in some breeds of dog.
After 15 to 20 generations we noted the appearance of foxes with
shorter tails and legs and with underbites or overbites. The novel
traits are still fairly rare. Most of them show up in no more than a
few animals per 100 to a few per 10,000. Some have been seen in
commercial populations, though at levels at least a magnitude lower
than we recorded in our domesticated foxes.
Alternative Explanations
What might have caused these changes in the fox population? Before
discussing Belyaev's explanation, we should consider other
possibilities. Might rates and patterns of changes observed in foxes
be due, for example, to inbreeding? That could be true if enough foxes
in Belyaev's founding population carried a recessive mutant gene from
the trait along with a dominant normal gene that masked its effects.
Such mixed-gene, or heterozygous, foxes would have been hidden
carriers, unaffected by the mutation themselves but capable of passing
it on to later generations.
As Morey pointed out, inbreeding might well have been rampant during
the early steps of dog domestication. But it certainly cannot explain
the novel traits we have observed in our foxes, for two reasons.
First, we designed the mating system for our experimental fox
population to prevent it. Through outbreeding with foxes from
commercial fox farms and other standard methods, we have kept the
inbreeding coefficients for our fox population between 0.02 and 0.07.
That means that whenever a fox pup with a novel trait has been born
into the herd, the probability that it acquired the trait through
inbreeding (that is, by inheriting both of its mutant genes from the
same ancestor) has varied between only 2 and 7 percent.
Second, some of the new traits are not recessive: They are controlled
by dominant or incompletely dominant genes. Any fox with one of those
genes would have shown its effects; there could have been no "hidden
carriers" in the original population. Another, subtler possibility is
that the novelties in our domesticated population are classic by-
products of strong selection for a quantitative trait. In genetics,
quantitative traits are characteristics that can vary over a range of
possibilities; unlike Gregor Mendel's peas, which were either smooth
or wrinkly with no middle ground, quantitative traits such as an
animal's size, the amount of milk it produces or its overall
friendliness toward human beings can be high, low or anywhere in
between. What makes selecting for quantitative traits so perilous is
that they (or at least the part of them that is genetic) tend to be
controlled not by single genes but by complex systems of genes, known
as polygenes.
Because polygenes are so intricate, anything that tampers with them
runs the risk of upsetting other parts of an organism's genetic
machinery. In the case of our foxes, a breeding program that alters a
polygene might upset the genetic balance in some animals, causing them
to show unusual new traits, most of them harmful to the fox. Note that
in this argument, it does not matter whether the trait being selected
for is tameness or some other quantitative trait. Any breeding program
that affects a polygene might have similar effects.
The problem with that explanation is that it does not explain why we
see the particular mutations we do see. If disrupted polygenes are
responsible, then the effects of a selection experiment ought to
depend strongly on which mutations already existed in the population.
If Belyaev had started with 130 foxes from, say, North America, then
their descendants today would have ended up with a completely
different set of novelties. Domesticating a population of wolves, or
pigs, or cattle ought to produce novel traits more different still.
Yet as Belyaev pointed out, when we look at the changes in other
domesticated animals, the most striking things about them are not how
diverse they are, but how similar. Different animals, domesticated by
different people at different times in different parts of the world,
appear to have passed through the same morphological and physiological
evolutionary pathways. How can that be?
According to Belyaev, the answer is not that domestication selects for
a quantitative trait but that it selects for a behavioral one. He
considered genetic transformations of behavior to be the key factor
entraining other genetic events. Many of the polygenes determining
behavior may be regulatory, engaged in stabilizing an organism's early
development, or ontogenesis. Ontogenesis is an extremely delicate
process. In principle, even slight shifts in the sequence of events
could throw it into chaos. Thus the genes that orchestrate those
events and keep them on track have a powerful role to play. Which
genes are they? Although numerous genes interact to stabilize an
organism's development, the lead role belongs to the genes that
control the functioning of the neural and endocrine systems. Yet those
same genes also govern the systems that control an animal's behavior,
including its friendliness or hostility toward human beings. So, in
principle, selecting
animals for behavioral traits can fundamentally alter the development
of an organism.
As our breeding program has progressed, we have indeed observed
changes in some of the animals' neurochemical and neurohormonal
mechanisms. For example, we have measured a steady drop in the hormone-
producing activity of the foxes' adrenal glands. Among several other
roles in the body, the adrenal cortex comes into play when an animal
has to adapt to stress. It releases hormones such as corticosteroids,
which stimulate the body to extract energy from its reserves of fats
and proteins.
After 12 generations of selective breeding, the basal levels of
corticosteroids in the blood plasma of our domesticated foxes had
dropped to slightly more than half the level in a control group. After
28 to 30 generations of selection, the level had halved again. The
adrenal cortex in our foxes also responds less sharply when the foxes
are subjected to emotional stress. Selection has even affected the
neurochemistry of our foxes' brains. Changes have taken place in the
serotonin system, thought to be the leading mediator inhibiting
animals' aggressive behavior. Compared with a control group, the
brains of our domesticated foxes contain higher levels of serotonin;
of its major metabolite, 5-oxyindolacetic acid; and of tryptophan
hydroxylase, the key enzyme of serotonin synthesis. Serotonin, like
other neurotransmitters, is critically involved in shaping an animal's
development from its earliest stages.
Selection and Development
Evidently, then, selecting foxes for domestication may have triggered
profound changes in the mechanisms that regulate their development. In
particular, most of the novel traits and other changes in the foxes
seem to result from shifts in the rates of certain ontogenetic
processes-in other words, from changes in timing. This fact is clear
enough for some of the novelties mentioned above, such as the earlier
eye opening and response to noises and the delayed onset of the fear
response to unknown stimuli. But it also can explain some of the less
obvious ones. Floppy ears, for example, are characteristic of newborn
fox pups but may get carried over to adulthood.
Even novel coat colors may be attributable to changes in the timing of
embryonic development. One of the earliest novel traits we observed in
our domesticated foxes was a loss of pigment in parts of the head and
body. Belyaev determined that this piebald pattern is governed by a
gene that he named Star. Later my colleague Lyudmila Prasolova and I
discovered that the Star gene affects the migration rate of
melanoblasts, the embryonic precursors of the pigment cells
(melanocytes) that give color to an ani- mal's fur. Melanocytes form
in the embryonic fox's neural crest and later move to various parts of
the embryo's epidermis. Normally this migration starts around days 28
to 31 of the embryo's development. In foxes that carry even a single
copy of the Star gene, however, melanoblasts pass into the potentially
depigmented areas of the epidermis two days later, on average. That
delay may lead to the death of the tardy melanoblasts, thus altering the
pigmentation in ways that give rise to the distinctive Star pattern.
One developmental trend to which we have devoted particular attention
has to do with the growth of the skull. In 1990 and 1991, after
noticing abnormal developments in the skulls and jaws of some of our
foxes, we decided to study variations in the animals' cranial traits.
Of course, changes in the shape of the skull are among the most
obvious ways in which dogs differ from wolves. As I mentioned earlier,
Morey believes that they are a result of selection (either natural or
artificial) for reproductive timing and smaller body size.
In our breeding experiment, we have selected foxes only for behavior,
not size; if anything, our foxes may be slightly longer, on average,
than the ones Belyaev started with 40 years ago. Nevertheless, we
found that their skulls have been changing. In our domesticated foxes
of both sexes, cranial height and width tended to be smaller, and
snouts tended to be shorter and wider, than those of a control group
of farmed foxes.
Another interesting change is that the cranial morphology of
domesticated adult males became somewhat "feminized." In farmed foxes,
the crania of males tended to be larger in volume than those of
females, and various other proportions differed sharply between the
sexes. In the domesticated foxes the sexual dimorphism decreased. The
differences in volume remained, but in other respects the skulls of
males became more like those of females. Analysis of cranial allometry
showed that the changes in skull proportions result either from
changes in the timing of the first appearance of particular structures
or from changes in their growth rates. Because we studied the skulls
only of adult foxes, however, we cannot judge whether any of these
changes are pedomorphic, as Morey believes they are in dogs.
The most significant changes in developmental timing in our foxes may
be the smallest ones: those that have to do with reproduction. In the
wild, foxes reach sexual maturity when they are about 8 months old.
They are strict seasonal breeders, mating once a year in response to
changes in the length of the day (in Siberia the mating season runs
from late January to late March) and giving birth to litters ranging
from one to thirteen pups, with an average of four or five. Natural
selection has hard-wired these traits into foxes with little or no
genetic variation. Fur farmers have tried for decades to breed foxes
that would reproduce more often than annually, but all their attempts
have failed.
In our experimental fox population, however, some reproductive traits
have changed in a correlated manner. The domesticated foxes reach
sexual maturity about a month earlier than nondomesticated foxes do,
and they give birth to litters that are, on average, one pup larger.
The mating season has lengthened. Some females breed out of season, in
November-December or April-May, and a few of them have mated twice a
year. Only a very small number of our vixens have shown such unusual
behavior, and in 40 years, no offspring of an extraseasonal mating has
survived to adulthood.
Nevertheless, the striking fact is that, to our knowledge, out-of-
season mating has never been previously observed in foxes experiencing
a natural photoperiod.
Forty years into our unique lifelong experiment, we believe that
Dmitry Belyaev would be pleased with its progress. By intense
selective breeding, we have compressed into a few decades an ancient
process that originally unfolded over thousands of years. Before our
eyes, "the Beast" has turned into "Beauty," as the aggressive behavior
of our herd's wild progenitors entirely disappeared. We have watched
new morphological traits emerge, a process previously known only from
archaeological evidence. Now we know that these changes can burst into
a population early in domestication, triggered by the stresses of
captivity, and that many of them result from changes in the timing of
developmental processes. In some cases the changes in timing, such as
earlier sexual maturity or retarded growth of somatic characters,
resemble pedomorphosis.
Some long-standing puzzles remain. We believed at the start that foxes
could be made to reproduce twice a year and all year round, like dogs.
We would like to understand why this has turned out not to be quite
so. We are also curious about how the vocal repertoire of foxes
changes under domestication. Some of the calls of our adult foxes
resemble those of dogs and, like those of dogs, appear to be holdovers
from puppyhood, but only further study will reveal the details.
The biggest unanswered question is just how much further our selective-
breeding experiment can go. The domestic fox is not a domestic dog,
but we believe that it has the genetic potential to become more and
more doglike. We can continue to increase that potential through
further breeding, but the foxes will realize it fully only through
close contact with human beings. Over the years, other investigators
and I have raised several fox pups in domestic conditions, either in
the laboratory or at home as pets. They have shown themselves to be
good-tempered creatures, as devoted as dogs but as independent as
cats, capable of forming deep-rooted pair bond's with human beings-
mutual bonds, as those of us who work with them know. If our
experiment should continue, and if fox pups could be raised and
trained the way dog puppies are now, there is no telling what sort of
animal they might one day become.
Whether that will happen remains to be seen. For the first time in 40
years, the future of our domestication experiment is in doubt,
jeopardized by the continuing crisis of the Russian economy. In 1996
the population of our breeding herd stood at 700. Last year, with no
funds to feed the foxes or to pay the salaries of our staff, we had to
cut the number to 100. Earlier we were able to cover most of our
expenses by selling the pelts of the foxes culled from the breeding
herd. Now that source of revenue has all but dried up, leaving us
increasingly dependent on outside funding at a time when shrinking
budgets and changes in the grant-awarding system in Russia are making
long-term experiments such as ours harder and harder to sustain. Like
many other enterprises in our country, we are becoming more
entrepreneurial. Recently we have sold some of our foxes to
Scandinavian fur breeders, who have been pressured by animal-rights
groups to develop animals that
do not suffer stress in captivity. We also plan to market pups as
house pets, a commercial venture that should lead to some interesting,
if informal, experiments in its own right. Many avenues of both
applied and basic research remain for us to pursue, provided we save
our unique fox population.
Lyudmila N. Trut is head of the research group at the Institute of
Cytology and Genetics of the Siberian Department of the Russian
Academy of Sciences, in Novosibirsk. She received her doctoral degree
in 1980. Her current research interests are the patterns of
evolutionary transformations at the early steps of animal
domestication. Her research group is developing the problem of
domestication as an evolutionary event with the use of experimental
models, including the silver fox, the American mink, the river otter
and the wild gray rat.
Morgan Lewis, RPh.
Member GSDCA
President Last Hope of Georgia 501c3
"So Much to Do, So Little Time"
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