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*Subspecies Purity vs. Generic Animals* *Scientific Dogma At Odds With

Reality * *By Michael Bleyman*

 

Did you even hear people talking about how healthy and well adjusted their

generic pound dog was compared to the high strung, temperamental, expensive

pure bred? Generics can be perfectly healthy, fine looking animals. In the

case of tigers and other endangered species where there are dwindling

numbers, strictly monitored genetic management must be maintained to insure

healthy offspring. If you have a limited gene pool, mixing subspecies is a

viable alternative to loosing the species altogether. The justification for

subspecies purity is largely a scientific/marketing argument. There may be a

bit too much science smothering reality. Does it really matter if a

particular tiger is a Sumatran or Bengal as long as tigers remain on this

earth.

 

When we speak about saving the tiger we must look at what is practical and

attainable. When a species as magnificent as the tiger is headed rapidly

towards extinction why are scientists, zoos, and many private preserves

trumpeting their adherence to subspecies purity when the species as a whole

is disappearing before their eyes? This is all based on scientific dogma and

a need to feel accepted by peers or monitoring, marketing, and licensing

organizations.

 

It's all a matter of money. How to get the donated dollar and how to keep it

coming. Successful marketing approaches exalt subspecies purity and exploit

young or unusual animals to enhance revenue. White tigers are a prime

example. I recently visited a conservation Web site that published the

following paragraph:

 

" Unfortunately, there are a lot of unwanted big cats in captivity today.

Most of them are tigers, lions, cougars, and bobcats. The tigers and lions

are mostly hybrids, (Hybrid and generic are not interchangeable. The use of

hybrid is incorrect.) or " generic " animals - the tigers are generally not

pure Bengal or Siberian subspecies, even if they are described that way.

Generic cats should not be bred, they are not an endangered species. Even if

they are purebred, they often come from over-represented bloodlines, which

is one reason they're not in a zoo. Also, zoos do not have room for all the

big cats in captivity today. The (omitted) does not take in cast-off pets,

because we simply have no room for these cats, there are so many of them.

And many so-called " rescue " places are breeding yet more, contributing to

the surplus animal problem. "

 

This pontificating extols the virtue of subspecies purity. There is no other

accepted alternative. However, no science is offered and no other viewpoint

explored. There is a need for subspecies purity as you will learn later in

this paper, but a species in danger of extinction needs broader alternatives

if survival is to be insured. Is this concept too simple to grasp or are

their other, more self serving motives involved? Let's analyze this

paragraph sentence by sentence. " Unfortunately, there are a lot of unwanted

big cats in captivity today. " This first sentence is absolutely true. There

are a lot of big cats in captivity housed in conditions that range from

wonderful to abysmal. " Most of them are tigers, lions, cougars, and

bobcats. " This second sentence is good, but one might add servals to that

list. " The tigers and lions are mostly hybrids, or " generic " animals - the

tigers are generally not pure Bengal or Siberian subspecies, even if they

are described that way. " This third sentence mentions hybrids or " generic " .

These terms should not be used interchangeably. Even though Webster's has

one definition of hybrid as, " anything of mixed origin " , the more accurate

definition they include is, " the offspring of two animals or plants of

different species.. " A hybrid would be a cross between a tiger and a lion,

now called a liger. These hybrids are used as attractions, but are of little

use elsewhere. A generic tiger, for example, would be the offspring of a

Bengal and Sumatran union.

 

" Generic cats should not be bred, they are not an endangered species. " This

fourth sentence really supports a view based on scientific dogma rather than

logical thinking. At one point in time, actually not too long ago, there was

no subspecies distinction in tigers. These distinctions were made recently

based mostly on geographical location. Take a look at the following excerpt

from a paper written by Mr. Singh.

 

Billy Arjan Singh: Founder of Tiger Haven-India. Mr. Singh is probably the

leading tiger conservationist in the world. He is the only man to

successfully reintroduce a generic tiger, one named Tara, into Dudhwa

National Park. This was met with furor by the scientific community. He has

been on the front lines of this fight to save the tiger for many years, but

has been met with indifference and criticism for his heroic efforts. He was

instrumental in India's Project Tiger which was initiated in 1972-73. His

suggestion to adopt the tiger as India's national animal was accepted by the

Indian Board for Wildlife. Here are a few thoughts from Mr. Singh.

 

" The compartmentalization of subspecies is possibly too dogmatic? It should

be for consideration that generic tigers which are recommended for

extinction should redeem their unfortunate existence by repopulating

selected habitat areas of erstwhile Balinese, Javan and Caspian occupation,

for these tigers are already in a process of a genetic transition.

 

It is a fact that tigers have a common ancestry, and this theoretically

predicates that an outsize Siberian could evolve into a undersized Balinese.

Yet though the subspecies are disappearing one after the other, scientific

dogma insists that racial purity must be preserved, and that generic [ i.e.,

of unknown lineage] tigers in zoos should be earmarked for extinction in

accordance with a carefully maintained studbook.

 

It should be the endeavor of the various countries who have lost their tiger

subspecies to re-colonize these vacant habitats. This might be done by the

introduction of generic tigers and their progeny, which are earmarked for

destruction. Hopefully their modified morphology would at some stage in the

evolution to reestablish the Balinese, Javan, and Caspian, subspecies.

Generic tigers are genetic transients who can reclaim an inheritance and not

pariahs bred for extinction. "

 

There is a problem, especially in this country, with unregulated breeders

who have no regard for sound genetic management. They breed to sell. As long

as the average person is allowed to purchase these animals backyard breeders

will remain. Legislation needs to be enacted to strictly limit the ownership

of these wild animals. This would in effect put many of these breeders out

of business. Likewise, there are people who breed these animals for show in

their private preserves to make money from visitors and donors. Baby animals

are attractions. Again there is little or no regard for sound genetic

management. As long as the USDA continues to license these establishments

without placing strict controls on breeding they will continue with business

as usual. Breeding for the wrong reasons does nothing to enhance the gene

pool or save the species.

 

If you consider the entire tiger population as a whole in the US you might

find the majority to be inbred and of little use in furthering the survival

of the species beyond a given point in time. The remaining tigers, if

managed properly, could sustain the species.

 

The writer goes on in the sentence to say the generics are not an endangered

species. Technically, from a purely scientific viewpoint, this is true. But

from a rational standpoint, given the tiger is almost extinct in the wild,

the argument becomes ridiculous. The tiger as an entire species is nearing

extinction. If you could line up one each of the remaining five subspecies

and ask an adult or a child what they see I bet they would say tigers. So

one is a little bigger, one a little darker, but they are still tigers. The

concern should be can we as a species save the tiger as a species? Generics

should be included, since they are, after all, tigers.

 

The sentence might also lead one to believe that generic tigers are

unhealthy for some reason. Many are due to inbreeding, but many are healthy,

viable animals. Using sound genetic management techniques with a large

enough population of unrelated pairs you can have a healthy and sustainable

tiger population.

 

" Even if they are purebred, they often come from over-represented

bloodlines, which is one reason they're not in a zoo. " This next sentence

does not make a lot of sense. If there is a blood line that is over

represented then why are they not being reintroduced into the wild? Answer -

more politics. This is not the reason these tigers are not in zoos. Zoos

keep tigers because they are a major draw to the facility, but they keep

only so many because they are expensive to house. It sounds impressive to

say these tigers are pure Bengals or pure Siberians. It looks good to have a

Species Survival Plan plaque adorning their cages or habitats. What happens

to these cats when they become old or infirm? That's a question you may want

to ask you zoo curator. I've visited zoos where I viewed a snow leopard

housed in a small, steel bared cage. It had barely enough room to walk

around. Prominently displayed on the front of the cage was a SSP plaque. So

what? The conditions this single animal had to endure were disheartening.

Its all for show. It attracts visitors and it raises money. Zoos have these

animals primarily for one reason - as attractions. They are not designed or

structured to save a major species.

 

" And many so-called " rescue " places are breeding yet more, contributing to

the surplus animal problem. " In this final sentence the writer mentions

so-called " rescue " places. What I did not show you was the list of rescue

facilities they included. The writer leaves it to the page visitor to

determine whether a listed facility is good or bad. More than likely the

reader will assume they are bad and never visit the sites. This practice is

suspicious at best. The Zoe Foundation, Inc. was listed in the 'Rescue'

group. If you read over my site you will see I do not own nor rescue tigers.

I am a product designer raising funds through sales for a new facility

designed to save the tiger as a species. I worked with a world renowned

tiger scientist studying tigers and methodology. This shows how well the

writer reviews listed sites. I have since requested removal from their list.

 

Good rescue facilities are needed to house the abandoned and unwanted 'pets'

purchased from breeders. A good rescue facility, and I know several, do not

breed these animals. They supply care and housing for life. It is a total

commitment. These organizations should be applauded and supported for their

efforts.

 

That simple paragraph is a small example of how things are generally

presented to the public. I could relate horror stories about some of the

people I have met working in this arena. I have written many mainstream

scientists, preserve directors, and fund raisers about this project, but I

have received little or no response. Could it be that a facility designed to

successfully save the species would pose a threat to their programs and fund

raising campaigns? Or are these people simply rude and self serving? Or do

they just not tolerate outspoken people with incompatible views? There is

one word that covers the entire spectrum - politics.

 

To put this into a little better perspective I would like you to read a

comment by a research scientist at a major university in the USA who

specializes in genetics.

 

*Dr. Alan C. Whitmore Ph.D.

Research Associate

Department of Microbiology and Immunology*

 

" A subspecies is simply a geographic division of a species. For example,

taxonomists (scientists who study the systematic division of organisms into

groups based on differences between the groups) have examined many

individual tigers and found enough physical differences between tigers from

different geographical locations to divide the tiger species into five

living subspecies: Bengal, Siberian, Chinese or Manchurian, Indo-Chinese,

and Sumatran.

 

The problem arises when subspecies distinctions are used to set captive

breeding policy. The Captive Breeds Specialty Group (CBSG) of the

International Union for the Conservation of Nature has decided that all

subspecies must be preserved in captive breeding. No " generic " animals are

included in the Species Survival Plans and no cross-subspecies captive

breedings are sanctioned. I have heard two reasons for this short-sighted

policy:

 

1) Some conservationists believe that a subspecies might have evolved a set

of genetic adaptations that make it particularly suited to its geographic

home range and that cross-breeding might dilute these adaptations to produce

a generic stock poorly adapted to the home range of either parental lineage.

This is a very unsatisfactory argument because it is unscientific and

completely unfounded in real-world experience: when subjected to very

exacting genetic analyses, most subspecies differences are miniscule

compared to ordinary individual differences.

 

2) The other argument is political and states that if it ever becomes

possible to reintroduce an endangered species into reclaimed habitat in

country A, the local politicians will only want genetically-pure, captive

bred A subspecies animals, unspoiled by racial mixing with inferior, foreign

animals. This is another argument that anticipates a not-yet-existent

problem; attributing to officials in the third world a measure of

narrow-minded provincialism that they have not yet shown.

 

Neither of these arguments carries any weight whatsoever in the face of the

real problem with subspecies: more than 99% of all subspecies are so rare in

captivity that if strict subspecies purity is preserved, the species as a

whole will be inbred to extinction within a very few generations. For

example, the cougar is divided into 29 subspecies: 13 North American and 16

Central and South American. The 1995 ISIS Mammal Abstract lists only 15 of

these subspecies in captive breeding programs. For six of these subspecies,

only males or females are held. Under the current CBSG policy, these six

subspecies are doomed to extinction in captivity and, probably, in the wild.

They could, potentially, contribute their outbred genetic diversity to the

production of a healthy, genetically-sound population of generic cougars

that would ensure that the cougar, as a species, survives in captivity.

These captive generic cougars could provide a robust breeding stock capable

of filling the large carnivore role in a wide variety of New World

ecosystems. "

 

To further clarify this situation I would like you to read a paper given to

me by renowned zoologist and tiger scientist Dr. Michael A.

Bleyman<http://www.zoetigers.org/bleyman2.html>.

Many scientists do not agree, but one must consider their reasoning. Saving

one's job or specific program plays an important if not predominant role in

the decision making process. Keep that in mind when considering people's

motives. This paper is somewhat technical, but it is very important when it

comes to better understanding subspecies categories.

 

* " Difficulties in Dividing Species into Sub-Species Categories*

 

The problem that now baffles taxonomists and vexes conservation biologists

is how (or whether) to divide species into infraspecific categories, what to

call these categories and what is the biological significance of these

distinctions.

 

It is obvious that species can be divided into clearly recognizable

subdivisions that still meet the criteria for inclusion within a species.

The human species, for example, can be divided into races on the basis of

skin color, hair texture, and the ability hit the open jump shot. The

several races fill the same role in the ecosystems they inhabit and can

successfully interbreed.

 

Linnaeus only recognized one subdivision of the species, called the variety.

The variety was defined as any deviation from the type of that species.

Because the essentialist notion of a species is now largely discredited,

this term is no longer used with a specific definition. Other subspecific

divisions are occasionally used: The terms cline, isophene, deme, phenon,

and variant have all been used with definitions of varying precision and

utility.

 

The infraspecific category with the widest current acceptance is the

subspecies. Mayr defines a subspecies as " an aggregate of phenotypically

similar populations inhabiting a geographical subdivision of the range of

that species and differing taxonomically from other populations of that

species. " This definition is full of complex notions and deserves a careful

dissection. First, notice the term " phenotypically similar populations. "

'Phenotype' is a genetic term that means " how an organism looks " or what

laboratory tests can tell you about how an organism functions. It is always

compared and contrasted with the 'genotype' of an organism: the sum total of

genetic material with which that organism has to operate. This phrase alerts

us to the fact that the division of a species into subspecies will be made

largely by visual (subjective) criteria and not by adaptive (behavioral) or

genetic (objective) criteria.

 

The most important phrase in this definition is " inhabiting a geographical

subdivision of the range of that species ... " . As Mayr says, " No

non-arbitrary criterion is available to define the subspecies, nor is the

subspecies a unit of evolution except where it happens to coincide with a

geographic or other genetic isolate. " To drive home this point, Mayr states

that " when an author reports several subspecies of one species from the same

locality, it strongly indicates an incorrect use of the term. " It is

apparent from this discussion that the only legitimate criterion for

dividing species into subspecies is geographical separation. Taxonomists

have therefore applied very little division into subspecies to those species

that have significant proclivities to wander and migrate, such as migratory

birds, whales, and humans.

 

The definition also includes the curious phrase " .. and differing

taxonomically from other populations of that species. " What does this mean?

Other than geography, what criteria do taxonomists consider sufficient for

the division of species into subspecies?

 

Consider the following example. Tigers exist in continuous populations and

they also exist as separated populations. If we were to present you with

tigers in two adjacent compounds and were to tell you that one was a

Sumatran tiger (Panthera tigris sumatrae) while the other was a Siberian

tiger (Panthera tigris altaica) how are you to know whether the two

(slightly dissimilar) tigers are exemplars of two distinct subspecies or

examples of the fundamental variability that makes members of the same

species look slightly different from one another? This is easy since Siberia

is far away from Sumatra and the two land masses have probably been isolated

for tens of thousands of years. Therefore, they can be said to form two

distinct subspecies. If I present the same two tigers and claim that they

are from India and Thailand then your choice is somewhat more difficult, but

you will eventually decide that they are from different subspecies because

Mayr's definition specifically mentions " geographic subdivision " and your

World Atlas clearly marks Thailand as being geographically distinct from the

Indian subcontinent. If, however, I state that these two tigers come from

two adjacent valleys in India and present the additional data that several

native hunters from that region have said that they have never seen a tiger

travel from Valley A to Valley B, then you have a real problem. To solve

this problem it will require a careful taxonomic investigation, because Mayr

has clearly stated that geographically separated populations can only be

separated into subspecies if they differ " taxonomically " from other

populations of that species. The taxonomist will examine the two specimens

and determine whether they differ 'phenotypically' enough to be classified

into different subspecies.

 

*Problems with the Subspecies Concept *

 

Mayr cautions taxonomists against the naming of local populations which

differ insignificantly as separate subspecies because the establishment of a

subspecies should be based on some biological or evolutionary distinction.

For example, the Chatham County population of white tailed deer and the Wake

County population of deer are not distinct subspecies. They are perfectly

adequate " geographical " descriptions but do not indicate subspecies of deer.

These two populations of deer can interbreed in the wild near the border

between the two counties and the offspring are fully capable of surviving in

either county. Similarly, any captive breeding program which interbreeds

wild-caught animals from the two counties does no damage to the deer gene

pool by mixing the two populations.

 

Most modern taxonomists have chosen to ignore Mayr's advice and use the

subspecies as casual descriptive nomenclature for any geographical

population. This unnecessary proliferation of subspecies has brought into

focus four aspects of the subspecies as a working classification that makes

it much less useful and instructive than does the concept of species:

 

1) *Different characters, such as tooth size, coat color, tail stripes, or

the frequency of specific isozyme alleles, (see biochemical genetics) show

independent trends of geographical variation. *

 

There is a taxonomic concept called the cline which is defined as a graded

series of morphologic or physiologic differences exhibited by a group of

related organisms usually along a line of environmental or geographic

transition. For example, since the early days of classic descriptive

taxonomy, two important north-south gradients of physical characteristics

within a species have been observed. Members of a species living near the

equator tend to be 1) smaller and 2) more darkly pigmented than members of

the same species living in more northern latitudes. Comparison of specimens

from extremes of a species range may seem to indicate two geographically

distinct subpopulations. However, if one looks at a continuum of a

population of a species running from north to south, sampling from the

entire range, it is probable to have larger and paler tigers in the north,

smaller, redder tigers in the south, and tigers of intermediate size and

color in the middle of the range. This does not make them different

subspecies.

 

Why not? A subspecies is supposed to represent a subpopulation with clear

differences from the rest of the species. Built in to the definition of a

subspecies is a need to show a discontinuity.

 

2)* Polytopic Subspecies*

 

There are many instances of the occurrence of phenotypically

indistinguishable populations in different geographic areas (which

taxonomists call polytopic subspecies). These populations are often divided

into subspecies when taxonomists feel that further study might discover some

trait or characteristic by the two populations differ in some biologically

significant way.

 

3) *Microgeographic Races*

 

The subspecies themselves can be subdivided into an array of microgeographic

races that shade off into individual variability.

 

4) *Arbitrary Distinctions *

 

The degree of distinction which different taxonomists consider as justifying

subspecies separation is extremely arbitrary, quite unlike the criteria for

species separation. Distinctions are often made as a consequence of local

phenotypic variation. A good example of this within the Carnivora is the

" Rex " or " King " cheetah. The coat pattern of the King cheetah was first

thought to be a separate species. This conspicuous tabby variant was later

considered a subspecies. It is now known to be the result of the expression

of a single recessive gene which has slightly different frequencies in

different African cheetah populations. Similarly, black and spotted leopards

are not different subspecies, merely coat color variants.

 

Seizing upon a single arbitrary difference in order to define a subspecies

difference without looking at a broad range of physical and behavioral

characters is one of the most common taxonomic errors. One must be aware,

for example, of the wide variety of phenotypic variability that occurs

naturally in local populations, within a species. In a healthy population of

outbred animals there will be enough innate genetic variability to ensure

that random mating does not produce inbreeding and yield the resultant

problems associated with the expression of deleterious recessive mutations.

This variability, and the constant re-assortment of genetic material that is

the great advantage of sexual reproduction, assures that all members of a

single species will differ genetically, and therefore differ phenotypically.

 

 

The phenotype is the physical form of the organism. It is the expression of

the genes and their interaction with environmental conditions.

 

It is also very important to realize that all phenotypic variation is not

necessarily the result of genetic variation. Mouse geneticists have known

for years that individuals of inbred strains (which have been maintained by

brother-sister mating for as many as 150 generations and are therefore

identical at 99.999% of their genes) never look exactly the same. Even

within this genetically controlled context, because of random developmental

variations and the happenstance of unknown small environmental factors, skin

pigment cells don't always migrate to exactly the same places during

embryonic development and so coat color patterns are subtly different.

Embryonic tooth buds start out in slightly different positions so that adult

teeth grow in slightly different places, making head shapes individual and

unique. The environment is another non-genetic influence on phenotype. Diet,

and other factors such as, exposure to various microorganisms, chemical

insults and physical activity have enormous effects on the behavior,

physical appearance and health of inbred mice.

 

*Implications of the subspecies controversy for the captive breeding of

endangered species. *

 

The division of species into subspecies could be an amusing and diverting

intellectual exercise except when official conservation policy is

established on the basis of these divisions. De facto policy for captive

breeding of endangered species is set by the various " specialty groups "

within the Conservation Breeding Specialty Groups (CBSG) of the

International Union for the Conservation of Nature (IUCN). These groups

include wildlife biologists and Zoo professionals who study the distribution

and status of particular species or groups of species in the wild, issue a

Population and Habitat Viability Assessment based on this study and make

recommendations for the preservation of that species in captive breeding

programs, if necessary. Many of these specialty groups have decided to

preserve all subspecies distinctions by not sanctioning (and therefore

effectively prohibiting) all inter-subspecies matings in captivity.

 

Many species of carnivores are divided into an absurd number of subspecies.

In an ideal world with large and healthy captive populations of all extant

subspecies, and an infinite number of zoos and wild animal parks in which to

breed these subspecies, it might be prudent practice to maintain these

populations as genetic breeding isolates. There are two reasons for this:

 

1) Two geographical subpopulations of a species may have evolved genetic

isolating mechanisms in spite of morphological similarities. These

mechanisms may prevent inter-subspecies fertilization or may cause

inter-subspecies hybrids to be subfertile or infertile. Genetic isolating

mechanisms may be behavioral — courtship behavior, such as body postures and

actions that indicate arousal or receptiveness, may not be correctly

interpreted between isolated subpopulations; or they may be biochemical —

for example, the enzymes that allow the sperm to pierce the outer layers of

the egg may lack the ability to penetrate the eggs of females from isolated

populations. These genetic isolating mechanisms can evolve between

populations of animals from the extremes of the range of that species or

between island and mainland populations.

 

If two subspecies are truly reproductively isolated from one another, then

they are not subspecies at all, but sibling species or cryptic species. A

captive breeding program that involved two or more such cryptic species

would produce no offspring at all if the genetic isolation is absolute, or

if the isolation is incomplete, create sterile " mules " or subfertile

offspring.

 

Such isolating mechanisms (which are a normal feature of speciation, the

evolutionary process which creates new species) may account for previously

reported difficulties in several captive breeding programs which involved

specimens from the extremes of a species' range and which have been

described as " outbreeding depression. " For example, the Dourocouli, also

known as the Owl or Night monkey, Aotus trivergatus, was thought to consist

of five subspecies. When captive breeding was attempted, it was accomplished

only with unusual rarity. It was very rare to find fertile breeding pairs.

However, if there was a strict intra-subspecies pairing of mated

douroucoulis, then fertile breeding was much more common. Leonid Van Der

Boer and his colleagues (2) found that the window of taxonomic

discrimination had not been set narrowly enough to pick up the real species

differences. There were five different species of Douricouls. Practical

captive breeding policy enabled taxonomists to define species differences

that conventional taxonomic techniques were not discriminating or

sophisticated enough to detect.

 

In any captive breeding program there will be certain male-female pairs

which will never produce offspring. Careful observation and record-keeping

will reveal which pairs of animals need to be reshuffled into more fertile

pairings. If there is a systematic and general inability of two reputed

subspecies to produce fertile offspring then those two populations will be

established as separate (cryptic) species and the subspecies designation

will be abandoned. The two " subspecies " will then be given distinct species

names and managed as separate species.

 

2) Another argument against the interbreeding of subspecies in captivity

states that (even if two subspecies have not yet evolved into cryptic

species) hybridizing subspecies A [which has evolved certain adaptations

which make it exquisitely suited to inhabit environment A] to subspecies B

[which is likewise uniquely adapted to environment B] might breed a group of

individuals which is not well adapted to either of these environments.

 

The answer is one of practicality: most threatened or endangered species

have been assigned that status because of habitat destruction: environment A

and environment B simply do not exist anymore. The force which drives

habitat destruction is human population growth, a malignant and implacable

force which can only be reversed by environmental cataclysms so widespread

and severe that only starlings, rats and cockroaches could survive. The time

has come to recognize that within 50 years there will be no more " wild " and

the only living species on this planet will be weeds and vermin and those

species in carefully managed captive breeding programs.

 

The present financial reality is a situation in which zoos all over the

world (from the prestigious London Zoo to several municipal zoos in the

United States) are going broke and closing down. The resources, including

money, cage space, and personnel available for managing captive breeding

programs are rapidly decreasing. The IUCN needs to face reality: We no

longer have the luxury of maintaining separate captive-bred populations of

30 subspecies of cougar or 15 subspecies of ocelot. If we wish our

grandchildren to be able to see any living cougars or ocelots then we must

genetically manage all of the existing specimens in captivity so as to

preserve as much species-specific genetic variability as is possible. Yet if

we look, for example, at the registry of all ocelots in captive breeding we

see a rather pathetic scattering of subspecies spread out through the

world's breeding institutions. Many subspecies are represented by only one

or two individuals in captivity in the whole world (1). The entire weight of

practical experience suggests that these fragments of breeding populations

cannot be maintained with any success at all.

 

The example of small gazelle species demonstrates how difficult it is to

rescue a species from a truly tiny population. In 1973 the St. Louis Zoo

rounded up the last three known members of Spekes Gazelle (Gazella speki) in

order to try to perpetuate it. The difficulties in the struggle to save this

animal species were enormous and frustrating. Tempelton (3) recounted this

as a seesawing battle to remove the piled up deleterious genes. Under

continued effort to build the population up it grew from three to twelve.

Then it crashed to five. The number of Spekes gazelle climbed back to twelve

and then down to seven. Only recently has success been in sight (4).

 

*References*

 

1 E. Mayr and P. D. Ashlock, Principles of Systematic Zoology, 2nd Edition,

McGraw-Hill, New York, 1991.

 

2 van Der Boer et al. on the Owl Monkey

 

3 Templeton on Speke's gazelle

 

4 The current world captive population of Speke's gazelle is 20 after 18

years of breeding. Infant mortality is 45% see ISIS Mammalian abstracts

1992. "

 

I hope this paper has given you pause for thought. If the tiger is going to

be saved a managed facility dedicated to that species must be pursued. This

will be a very expensive undertaking if these animals are to be managed in

habitats worthy of their size and needs. That, however, is my goal in honor

of Dr. Bleyman who passed on in 1996. The tiger can be saved if enough

people put aside politics and concentrate on meaningful action.

 

 

 

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Thanks for the read, good article; must be fun stuff for the biotechnogeeks

to ponder. For me, this article could have ended here:

 

³There may be a bit too much science smothering reality. Does it really

matter if a particular tiger is a Sumatran or Bengal as long as tigers

remain on this earth?²

 

No. It does not matter. The destruction has been done. Let¹s face reality

and move on. Don¹t follow the path of ³divide and conquer² - work together

as scientists and normal people and fix the problem by returning all captive

animals to the closest place of origin as possible - and then protect the

habitats. Nothing could be simpler. In the words of Thoreau, ³Simplify,

Simplify, Simplify.² If it means that a lot of ³conservation biologists²

are out of a job, so be it. Have them adapt using computer models, or let

them retire into obscurity.

 

Jigs

Nepal

 

 

 

 

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