Muddying the waters with E. afghanicus?

[fuzzylogix]

I hate to see oversimplified ideas like "inbreeding is bad" or "outcrossing is good" parroted without critical thought. A breeder who takes the time to educate themselves is in a position to make better choices.

completely agree. just seemed like this thread was heading into persecution. one of the reasons i chose leopard geckos as my main breeding project was because of the huge genetic diversity and seemingly endless combinations of morphs. i am constantly researching genetics and it seems like i learn something new just about every single day. i am reproducing healthy, robust animals from my crosses so far, and if something does go awry in the future, then i will be able to pass on that knowledge to other potential breeders as well. i am in this for the love of the animals, and for the excitement of what the future holds for the species.

 

[Tony C]

Tony, could you please expound on what you mean by "blindly"?

Outcrossing based on the assumption that outcrossing is always beneficial without weighing the potential risks and benefits.

Why is it that mutt dogs have the least inherent issues?

Comparing dogs, which have been selectively bred from wolves with the intent to create unnatural forms is not a fair comparison to the crossing of natural species, subspecies, or distinct populations.

Outbreeding depression refers more to crossing dissimilar genes such as hybridization, and I really don't see it applying to the crossing of leopard gecko subspecies. Mother Nature has an incredible way of dealing with these hybrids, and the first one that comes to mind is the inability of the offspring to reproduce... like mules or ligers.

Interspecific hybrids are not always infertile, in some groups like the colubrid snakes there are even fertile intergeneric hybrids. The effects of outbreeding depression are not limited to interspecific hybrids, the potential exists even in crossing two genetically distinct populations of a single species.

 

[Golden Gate Geckos]

Thank you for clarifying your thoughts, Tony. I appreciate your opinions, and this stimulating topic!

 

[eric]

I find it interesting that this is coming up. Is this hobby full of that many dishonest people? Wouldn't one of us and there are a few of us that are out-crossing, wouldn't we have already discovered issues? And wouldn't we have disclosed those issues? I know I would've.

 

[Tony C]

I find it interesting that this is coming up. Is this hobby full of that many dishonest people?

A quick look at the BOI or a review of some of the "new morphs" in recent years (or months...) would show that the answer is a resounding "yes". For every breeder with your integrity there are probably 10 who would dump their problem animals on the market to recoup costs before the issues became public knowledge.

 

[Wild West Reptile]

I find it interesting that this is coming up. Is this hobby full of that many dishonest people? Wouldn't one of us and there are a few of us that are out-crossing, wouldn't we have already discovered issues? And wouldn't we have disclosed those issues? I know I would've.

I know several, and I mean SEVERAL top breeders who use the sub species all the friggin time and have ZERO issues with it. I'm getting really tired of all the "don't do it, you'll screw up the species and muddy the waters, and you have no idea what your creating" crap! Like several people have stated...they are doing it and having nothing but POSITIVE results! Go to Geckosetc. and have a look at Steve's selection of sub species. Steve is a pretty darn bright guy who not only breeds incredible geckos, but also spends alot of his time studying other species in the wild, and what have you, and is one of the more qualified, educated guys around on the subject. He uses them all the damn time and so do alot of other breeders. In my humble, useless, worthless opinion ....I feel that using them in a responsible way is nothing but positive. I know another breeder right now that is using them to get the tremper out of a particular morph in order to create a pure species and has had nothing but great results!
So for those of you who are using them to create a better, purer species, I say carry on and don't listen to the nay-sayers who aren't even working with them.
:main_thumbsup:

 

[eric]

A quick look at the BOI or a review of some of the "new morphs" in recent years (or months...) would show that the answer is a resounding "yes". For every breeder with your integrity there are probably 10 who would dump their problem animals on the market to recoup costs before the issues became public knowledge.

Tony, I respect your point :main_thumbsup:

 

[eric]

I know several, and I mean SEVERAL top breeders who use the sub species all the friggin time and have ZERO issues with it. I'm getting really tired of all the "don't do it, you'll screw up the species and muddy the waters, and you have no idea what your creating" crap! Like several people have stated...they are doing it and having nothing but POSITIVE results! Go to Geckosetc. and have a look at Steve's selection of sub species. Steve is a pretty darn bright guy who not only breeds incredible geckos, but also spends alot of his time studying other species in the wild, and what have you, and is one of the more qualified, educated guys around on the subject. He uses them all the damn time and so do alot of other breeders. In my humble, useless, worthless opinion ....I feel that using them in a responsible way is nothing but positive. I know another breeder right now that is using them to get the tremper out of a particular morph in order to create a pure species and has had nothing but great results!
So for those of you who are using them to create a better, purer species, I say carry on and don't listen to the nay-sayers who aren't even working with them.
:main_thumbsup:

Agreed! My crossings will continue and will be labeled as such. Until I discover an issue I'll continue to do so, but if I discover an issue you bet I'll be posting my results and order a self inflicted halt of said project.

 

[TokayKeeper]

Chris, you are such a tease! Don't just leave us hanging... inquiring minds want to know!

Let's just leave it at an exciting subspecies I wanted and purchased from a well respected, genetically informed breeder mentioned within this thread came in with severely kinked tails. I am being refunded and the geckos are being sent back. I've probably already said too much, so I won't name names and will continue to remain as vague as possible, publicly and privately, about this dealing.

I know several, and I mean SEVERAL top breeders who use the sub species all the friggin time and have ZERO issues with it.

One of those top, bright individuals just got notified by me last week of issues. See my comment above.

 

[Golden Gate Geckos]

Is this hobby full of that many dishonest people?

A quick look at the BOI or a review of some of the "new morphs" in recent years (or months...) would show that the answer is a resounding "yes". For every breeder with your integrity there are probably 10 who would dump their problem animals on the market to recoup costs before the issues became public knowledge.

We are not talking about new 'morphs', we are talking about leopard gecko sub-species that were not created in some breeder's tubs with a plethora of surprise genes. We also need to keep in mind that the BOI is brimming with 'bad guy' posts that we tend to flock to for the drama value, and very few 'good guy' reports get posted, much less noticed. Maybe I'm too altruistic, but I don't see 1-in-10 being an accurate representation of the ratio of good guys to bad guys. Perhaps on Fauna, but certainly not in the real world?

 

[M_surinamensis]

Outbreeding depression refers more to crossing dissimilar genes such as hybridization, and I really don't see it applying to the crossing of leopard gecko subspecies. Mother Nature has an incredible way of dealing with these hybrids, and the first one that comes to mind is the inability of the offspring to reproduce... like mules or ligers.

Tony already mentioned it, but I'd like to reiterate it because it's tremendously important; reptile hybrids often prove to be fertile with one another, back to both parent species and even to a third species. The causes of sterility in some hybrids are understood, it's not really a mysterious "nature doesn't like it and autocorrects" kind of scenario, any more than the fertility of reptile hybrids is an endorsement.


There are... lots of factors here. I'm going to comment on a few of them that came to mind while I read the thread. Make a snack, this may be one of those posts.


Taxonomy is among the more highly subjective disciplines among the biological sciences. As it stands right now, the bulk of recognized taxonomic designations are still a result of somewhat archaic observational methods. Many of those observances are turning out to be accurate when tested using more modern genetic mapping techniques, but some of them aren't and the overwhelming majority remain untested as a result of the time and expense involved in some of the newer approaches. The point being that subspecific designations in general aren't something that every approach to taxonomy and evolution even recognizes as being a valid distinction, and further that the approaches used in identifying conspecific populations of animals are something that is very open to review and reanalysis. The degree of deviance between subspecific populations and the areas of natural intergradiation are also of importance in a discussion of this topic; if intrinsic isolating mechanisms have developed among wild populations and divergent evolution can be cited, it's significant.

Any given population of animals is constantly experiencing a selection process which can be described as having a consequence of creating future generations which are better adapted to the conditions that their ancestors were subjected to. There are additional behavioral qualifiers associated with reproductive success, but these happen alongside the external pressures, mitigated by the inherent fitness and survival rates. Distinct populations, experiencing distinct environmental conditions and distinct ecological relationships, can potentially evolve in different directions. That is to say that they can develop divergent traits, it's a big part of why subspecies are considered subspecies when there's a geographic overlap without (or more commonly, with minimal) associated natural intergradiation. Those divergent responses to the process of selection can give rise to differences in; behavior, breeding strategy, physiology and form. Different populations can express different traits, this doesn't just apply to color, pattern or scale counts either, it can be far more complex adaptations of nutritional needs and organ function.

When crossing such divergent populations, the resulting combinations are often impossible to accurately and thoroughly predict in a meaningful manner. Taking genetic information from both parent animals and combining large swathes of traits from each can potentially result in conflicting or overriding genetic dictates, and introduces all traits (positive and negative) from both groups. The more divergent the parent animals are, the higher the chance for such conflicts to arise. Each group is expressing traits which evolved simultaneously inside their respective populations, to work as a cohesive whole- shuffling those traits together means combining those divergences. It risks the manifestation of extreme conflicting genetic dictates, the more divergent the traits, the more significant those conflicts can be should they arise.

Predicting the potential outcomes when dealing with extreme divergences is actually slightly easier in some respects. Crossing a parent animal that is adapted to low humidity to one that has adapted to high humidity, for example, may result in scales that are adapted to an arid environment (and are prone to infections when moist), but lungs which require high humidity for proper function (and are prone to infections when dry). When the populations are more similar, it can be more difficult to predict or identify such conflicts of function with that kind of ease. Minor differences in say... abdominal cavity capacity and organ volume, the shape and function of joints, the nutritional needs and the predisposition of immune responses are all far more difficult to measure (in a living animal, anyway) but equally important to the health and well being of the ensuing offspring.

Furthermore, the comparative unknowns, the unexpressed and dormant traits, lurking in the gene pool of both animals can manifest in truly unpleasant ways. Crossing the populations means crossing all those potential negatives into a group which had previously been insulated from them. Kinks and underbites, vitamin uptake difficulties, eye formation issues, a tendency to be susceptible to various illnesses... all of these things can manifest in an animal which does not have any associated genetic defenses against the problem.

There's also the ultimate effect on the populations that such crossed animals are introduced into. As much as there has already been damage done to the subspecific/localspecific purity of some captive populations of animals (leopard geckos among them), intentionally re-introducing hybrid and intergrade animals to the population is entirely counter to the idea of accurately quantifying and addressing the issue. Some of us, as individuals, may not have any particular objections to animals which represent undisclosed, unknown crosses... but some of us have strenuous and valid reasons for not wanting such animals. When these hybrids and intergrades are introduced, especially in the manner in which they all too often are, with poor histories and spotty disclosure, the entire captive population becomes contaminated and suspect. Pure animals ruin nothing, for anyone. Hybrids and intergrades taint populations in such a manner that anyone who wishes to work with a naturally occurring population has no option but to seek the (sometimes impossible to obtain) wild collected stock.

Which really leads in to the matter of scope and meaning. To my personal regret, our captive populations of many animals are bred in a manner that is wildly divergent from the traits which made those populations successful in nature. We propagate albinism and enigma syndrome, we breed for high contrast colors in ball pythons and bizarre pattern anomalies in everything. We do this because the selection process in captivity is formed around some very different factors than the selection process of wild populations. Predation is rarely an issue. Weak feeding responses are something we externally correct and overcome. Even extreme manifestations of counter-indicated traits, like neurological issues, are something we step in and control. We really have total, absolute, power over each generation of animals which is produced. We manipulate the success rate, we modify the environment the animals will encounter, we bend instinctive breeding behaviors to our own purposes in total defiance of the qualities which the populations themselves had been breeding towards for thousands of years. Some people see this as an excuse to do whatever they like, with no real thought given to all of the consequences, because they see the captive population as being inconsequential, as not mattering. I would argue the exact opposite, that our position imbues us with even greater responsibilities, because the consequences of our mistakes will not be corrected by a predator, a disease, or an inability to find a mate. We bear the burden of every choice, every pairing, every offspring... and it is a burden that far too few people live up to, blinded in their pursuit of what they think might look cool.

To allow all the weight of those responsibilities to be arbitrarily decided by whim and aesthetics is unbelievably short-sighted. By the time such problems as may manifest are expressed and obvious, it is far, far too late to address them.

 

[Golden Gate Geckos]

To allow all the weight of those responsibilities to be arbitrarily decided by whim and aesthetics is unbelievably short-sighted. By the time such problems as may manifest are expressed and obvious, it is far, far too late to address them.

The albino, the Enigma, the Spider Ball, and the Jaguar Carpet Python are excellent examples of this.

 

[justindh1]

I don't mean to side track the tread but can you explain why albinism is considered to along with the enigma? I am just curious now after reading M_surinamensis post which I found very informative on the subject of out-crossing. They are found in the wild many time and have been known to survive and produce offspring themselves. It just seems like some valuable information that I would like to know more about.

 

[M_surinamensis]

I'm not Marcia, but given the rest of the list I suspect she was probably referring to either Kahl line albino boas, which have a genetic propensity for eye deformities, or some species of diurnal animal, where the absence of melanin creates health complications as it interacts with the animal's need for UVB in order to synthesize D3. It needs intense light exposure, but intense light exposure without that pigment will damage the skin.

 

[Golden Gate Geckos]

I don't mean to side track the tread but can you explain why albinism is considered to along with the enigma?

Albinism is a genetic disorder, and very albino reptile species are found in the wild because they might not survive in nature given the reasons Seamus stated above.

 

[robin]

I'm not Marcia, but given the rest of the list I suspect she was probably referring to either Kahl line albino boas, which have a genetic propensity for eye deformities, or some species of diurnal animal, where the absence of melanin creates health complications as it interacts with the animal's need for UVB in order to synthesize D3. It needs intense light exposure, but intense light exposure without that pigment will damage the skin.

do you think the eye issues with the kahl strain albinos is due to inbreeding?

 

[Wild West Reptile]

Let's just leave it at an exciting subspecies I wanted and purchased from a well respected, genetically informed breeder mentioned within this thread came in with severely kinked tails. I am being refunded and the geckos are being sent back. I've probably already said too much, so I won't name names and will continue to remain as vague as possible, publicly and privately, about this dealing.



One of those top, bright individuals just got notified by me last week of issues. See my comment above.

How is this related to the subject at hand? I thought we were talking about using a sub-species to breed, not about getting animals with tail kinks. I can find you tail kinks in every morph made, so should we stop breeding all morphs? Did you get bad results after breeding a sub species? Because thats what i thought this thread was about....maybe im in the wrong thread? Why would you buy ANY morph without first seeing what your getting? If they were as bad as your saying, I would think you would see that in a picture, no?

Anyways, if you were buying them, I assume you were going to use them in some sort of breeding project? Am I wrong? My point was that if you start with a healthy, non deformed sub species and use it for whatever result you are striving for, it should not be a negative. People are making some really nice geckos with these guys and hopefully clearing up some morphs as well.

I'm not trying to pick a fight with anyone here, as I am well aware that I am nowhere near as knowledgable as alot of you but I just think you misunderstood my point.

 

[M_surinamensis]

do you think the eye issues with the kahl strain albinos is due to inbreeding?

Not exactly.

Inbreeding doesn't actually create genetic deformities. It just exponentially reinforces everything present inside the limited genetic pool, making it more probable that any traits which were possible will become manifest. Positive and negative traits have equal chances of expression.

That exponential reinforcement can make such manifestations apparent faster than would be the case with extensive outbreeding.

In the case of the Kahl albinos and the eye problems, Pete refuses to discuss it, so all that exists is some educated guesswork. The likely scenario is that the negative trait (eye problems) was introduced into the project at a very early stage, within the first couple generations of the project is probable. It may or may not have been apparent that the negative genetic trait was in the project, it may have been introduced by an animal who was not displaying issues, but was a genetic carrier. The tendency to intensely line breed when establishing such a project with a limited pool of genetic material, followed by the effort to reproduce it as widely as possible, is what helped make it apparent that the negative trait was associated with the line within a few years (generations) of the trait hitting the open market.

The types of breeding projects used for something like that when compared to the introduction of Afghan stock in leo populations will be a bit different, there's a little bit less of that frenzied rush to reproduce when not dealing with a single mutation, but the same underlying concept applies- that the combination may be laying the foundation for a negative trait, which is present in the genetics of either parent population (or created through the choice to combine them) which may not become readily apparent for a number of generations. By the time such a problem animal does crop up, the lineages have been propagated substantially and spread outside of the control of the originator- which makes fixing it a little like trying to put toothpaste back into a tube.

The consequences aren't guaranteed to be negative, but the possibility exists of conflicts arising from the divergent morphology in a way that is not exactly a longshot, and there are a lot of unknowns when it comes to the natural history that might help clear up some of the questions. A natural band of common intergradiation, for example, would be meaningful evidence, but its absence doesn't necessarily prove anything.

 

[TokayKeeper]

How is this related to the subject at hand? I thought we were talking about using a sub-species to breed, not about getting animals with tail kinks. I can find you tail kinks in every morph made, so should we stop breeding all morphs? Did you get bad results after breeding a sub species? Because thats what i thought this thread was about....maybe im in the wrong thread? Why would you buy ANY morph without first seeing what your getting? If they were as bad as your saying, I would think you would see that in a picture, no?

Anyways, if you were buying them, I assume you were going to use them in some sort of breeding project? Am I wrong? My point was that if you start with a healthy, non deformed sub species and use it for whatever result you are striving for, it should not be a negative. People are making some really nice geckos with these guys and hopefully clearing up some morphs as well.

I'm not trying to pick a fight with anyone here, as I am well aware that I am nowhere near as knowledgable as alot of you but I just think you misunderstood my point.

I, nor the breeder saw the kinking in the photos available on their website. Supposedly an employee package the geckos, so the breeder was unaware of the issue until I pointed it out. Had they been evident within the photos on the website then I would not have purchased the geckos. When I talk kinking, I'm not talking about the ones often seen in photos, where the tail tip is kinked. I can show you photos of that all day too. The kinking in this case starts about 3/8 inch from the pelvis and extends about 1/2 to 3/4 inch down the tail within the central portion of the tail. What saddens me is that it wasn't on just one gecko, but present at almost the exact same location on both geckos which are of the same subspecies. Even more saddening is the question of how many others were sold without "knowing" of the issue.

I, vaguely, mentioned what I did as it pertains to the assumptions at hand regarding outcrossing within the thread. The geckos I purchased, and need to mail back, were of "pure" subspecies status yet they are already showing genetic abnormalities.

 

[M_surinamensis]

Just to expand a little bit on what I mean when I mention conflicting morphological tendencies...

Subspecies can be very similar in some cases, or they can be rather different, in others. In the case of Afghan leopard geckos, there's some question of if they should even be categorized as a subspecies, or if they are a unique species in their own right. They're smaller, they have different proportions to their various body parts, the length of limbs, size of the abdomen, the relative size of the head and eyes, the exact shape of the jaw... similar, but slightly different in a noticeable way.

Consider, for a moment... something like a knee joint. The way the bones are shaped to work in conjunction with one another, the way the connective tissue fills in the spaces and determines the direction it can bend, the way the proportional length of the limb and weight of the body all come together to form the stride. The degree of evolutionary precision that has gone into something as simple as that one body part, all the countless generations breeding towards that exact end product (which in turn will inform the generations to come)... it's astounding.

Now consider the idea of knees from two different animals. Different shapes, different angles and strengths and muscle growth and connective tissues. Consider what happens if the parts from one are crammed in with parts from the other, if the shape of the bones doesn't line up as well, if there's a ten degree difference in the direction the joint can bend. Consider what that would do to the ability of the animal to walk, how it might be painful, or crippling.

Now consider just how many body parts, how many organs, how many bones, how many muscles and blood vessels each animal has. How many of them can be combined with something incompatible, how many ways it can go wrong. And how difficult it would be to tell without microscopic dissection. How difficult it would be to predict, from individual to individual, as the genetics are shuffled together like a deck of cards with each egg produced. How long might it lay hidden, before it is obvious? How tough would it be to trace it all backwards to the exact pairing that caused the combination and undo it?

Consider the risks. Now consider the rewards. I don't think they're proportional at all. "It looks cool and I haven't had any problems yet" is a pretty crappy justification for shuffling that deck.