Is this true?

[jojackson]

A lone Female V komodoensis produced viable eggs that hatched at a UK zoo a few years ago.

http://www.nature.com/nature/journal/v444/n7122/abs/4441021a.html

http://www.npr.org/templates/story/story.php?storyId=6667721

Some Gecko species are said to parthenogenic also, Bynoe's Gecko - Heteronotia binoei

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1204568

http://www.pilbarapythons.com/binoesgecko.htm

 

[viaje]

That really depends who you ask. The practise has unfortunately resulted in a lot of very unhealthy animals.

I know many breeders who have been breeding for close to 30 years, they have spent nearly their entire lives researching pedigrees and genetics. These people know nearly everything there is to know about their breeding stock and have spend thousands upon thousands of dollars testing for health problems. With the extent of knowledge these people have there is no problem with them line breeding. Yes, some back yard breeders and puppy mills caught on and decided to do it as well- but if people left breeding to the professionals, everyone's dogs would be infinitely healthier.

Unfortunately, I have a feeling that people wouldn't know where to start with chameleons when looking for health issues that might arise from line breeding- so I don't think it would be responsible.

 

[sandrachameleon]

I know many breeders who have been breeding for close to 30 years, they have spent nearly their entire lives researching pedigrees and genetics. These people know nearly everything there is to know about their breeding stock and have spend thousands upon thousands of dollars testing for health problems. With the extent of knowledge these people have there is no problem with them line breeding. Yes, some back yard breeders and puppy mills caught on and decided to do it as well- but if people left breeding to the professionals, everyone's dogs would be infinitely healthier.
Unfortunately, I have a feeling that people wouldn't know where to start with chameleons when looking for health issues that might arise from line breeding- so I don't think it would be responsible.

I wasnt talking about backyard breeders or puppy mills (which are bad), but kennel club dog breeders (many of which are bad). Not all of course, but far too many pure bred dogs are in fact bred for looks, not health or practicality.

But at least those breeders have some idea about the health issues they are fostering. Chameleon line breeding seems an undesirable option.

 

[Pure]

I wasnt talking about backyard breeders or puppy mills (which are bad), but kennel club dog breeders (many of which are bad). Not all of course, but far too many pure bred dogs are in fact bred for looks, not health or practicality.

But at least those breeders have some idea about the health issues they are fostering. Chameleon line breeding seems an undesirable option.

Indeed, greed often is the main culprit behind these unhealthy animals. A lot of these breeders have no regard for the health of the animals as long as they are "living". So they do not destroy the ones that should be destroyed, when they can sell them for top dollar.

Really my thoughts (and this is pure speculation) around the stigma behind line breeding in chams has little to do with the health of the animal. I think the local purist mentality bleeds over when people start talking about line breeding. People are so passionate about keeping these lines pure that the thought of line breeding scares the sh*t out of them. Line breeding often results in new morphs. And for the purist this would be a terrible thing. I would never line breed for a new morph, but once it's proven and documented that it can be done if done right...It's only a matter of time before you start seeing more designer panthers and plenty of other species. Imagine a solid white panther. It would be a very pretty animal but man would it cause a stir.

Personally I wouldn't line breed panthers. I'm one of these purist and honestly feel some of the different locals should be genetically tested to see if they can be classified as different sub species. But as I tend to think with an open scientific mind, I wouldn't scoff at someone trying it.

Now veileds are a different story.

 

[chequepoint]

Now veileds are a different story.

Because they're cheaper.

 

[merumontanus]

Just when you think you know what your talking about....mother nature breaks all the rules.

http://www.dailytexanonline.com/life-arts/ut-lab-studies-gender-bending-lizard-mating-1.971713

http://en.wikipedia.org/wiki/New_Mexico_Whiptail

Parthenogenesis has absolutely no relevance to line-breeding in non-parthenogenetic species. It's like saying inbreeding is acceptable because there are organisms on Earth that are asexual-- like amoebas.

Don't confuse the two.

That inbreeding occurs naturally (in the wild) in certain species is one thing, but to say that this less frequent event should be practiced in captivity because it's "natural" is a blatant fallacy.

Fabián

 

[jojackson]

I think that sheer numbers bred in captivity, greatly increases the odds of 'compatible' animals being paired, resulting in spontaneous mutations (that will be deliberately propogated as new morphs), compared to the odds of the same thing in the wild, which is unlikely to be carried on in future generations.
These pairings in captivity wont always be deliberate and selective, on the part of the breeder, but as sheer numbers increase, will become more random (accidental).
Desirable traits such as color and pattern are obvious and visible, genetic data is not.

How long till breeding the species becomes either:

A) Prohibitively expensive for an would be breeder to aquire animals of particular linage for breeding stock (known 'pure' localities)
B) An entirely hit & miss affair bordering on a lottery, even when paying Good $

At some point, the captive genepool becomes a luckydip. Then what? get new blood from the wild ofcourse? NO!
How big is madagascar? How big is the chameleon hobby? Eventually, the wild genepool becomes smaller and smaller too, as a result of desperate imports for new blood, and whats the result in the wild? Think about it!

 

[Pure]

Because they're cheaper.

Actually price has little to do with it IMHO. Veileds are literally falling out of trees here in Florida. Getting new, clean genetics will almost certainly never be a problem. Where as JJ put it better, inbreeding what captive stock we have here in the States and in other countries, combined with their popularity, will eventually make getting clean genetics problematic in the Panther species.

Not to mention we are in the infancy of what colors can be produced with veileds. I see great promise with them. Do we really need more color morphs with panthers? It's hard enough to keep track of all the locals as it is.

 

[chequepoint]

Actually price has little to do with it IMHO. Veileds are literally falling out of trees here in Florida. Getting new, clean genetics will almost certainly never be a problem. Where as JJ put it better, inbreeding what captive stock we have here in the States and in other countries, combined with their popularity, will eventually make getting clean genetics problematic in the Panther species.

Not to mention we are in the infancy of what colors can be produced with veileds. I see great promise with them. Do we really need more color morphs with panthers? It's hard enough to keep track of all the locals as it is.

Do we need more color morphs of any animals? I'm all about enjoying what nature has to offer, and very against trailer park genetic engineers in florida seeing what color they can make their snake.

 

[Pure]

Eh there will always be 2 sides to this coin. I do take a little offense to "trailer park genetic engineers in florida" but I know you didn't mean that pointed at me. I don't live in a trailer park. But amateur genetic engineers has nothing to do with it. Genetics is just a side effect of breeding any animal and it just so happens to play a larger role when you deal with line breeding. I don't think many, if any people line breeding think of themselves as a genetic engineer. To do so would be foolish. And why pic on Florida? It's not like we are the only state capaple of breeding for specific traits.

When I mentioned veileds falling out of trees here, well it's simple, they can live and thrive here.

 

[chequepoint]

All humor aside, those veilds in florida are coming from a relatively shallow gene pool to begin with, and quite frankly need to be rounded up put down. They pose a severe threat to the local environment, and thus the hobby. They are not an argument for anything positive in the hobby.

 

[summoner12]

Veiled have great color and personality... haha

Karate CHOP!

 

[summoner12]

They are not an argument for anything positive in the hobby.

Sure they are..... natural sunlight creates monster veileds..... and... good bug selection promotes growth... oh, and Darwin really plays a roll in producing some mean ole monster veileds.

Although I do agree with you on the aspect of how they will damage the hobby... they are just an example of how chameleons can be invasive.... even though most species wouldn't stand a chance in most of the US Even in parts of FL and CA, only some might be able to make it alone.

 

[Pure]

All humor aside, those veileds in Florida are coming from a relatively shallow gene pool to begin with, and quite frankly need to be rounded up put down. They pose a severe threat to the local environment, and thus the hobby. They are not an argument for anything positive in the hobby.

I totally agree, well mostly. They do need to be rounded up. But no one knows how limited the gene pool is. They've been released in the wild for a very long time and for many reasons. Owners just dumping unwanted animals and a crap load of them came from the Hurricane Andrew incident that is accredited for the vast amount of wild pythons and boas running wild down there. Snakes weren't the only reptiles those flooded out shops had in them. Not to mention the ones that got out from breeders during that hurricane.

But them being good or bad is a discussion for another thread. My point was simply that they will never be eradicated. Even if they are, there is a large enough population in their natural habitat, and their demand isn't high enough to ever make getting clean genetics a problem.

edit: Well "ever" is a pretty bold assumption, maybe "not in the foreseeable future" would be better.

 

[desultadox]

omg i feel embarrassed i though we were talking adults oh my god im stupid

Of course we're talking adults, juveniles aren't sexually mature and can't reproduce with anything, let alone their own relatives.

I'm sort of shocked this is even a discussion, given how adamant people are about keeping pardalis bloodlines squeaky-clean. Morph mixes are treated like a criminal offense, one would expect inbreeding to be the ultimate sin. Now that I know this is practiced though, I will never purchase a chameleon from a Kentucky breeder!

 

[jojackson]

Food for thought

Point#1 Outbreeding depression

In evolutionary biology, outbreeding depression refers to cases when offspring from crosses between individuals from different populations have lower fitness than progeny from crosses between individuals from the same population. This phenomenon can occur in two ways. First, selection in one population might produce a large body size, whereas in another population small body size might be more advantageous. Gene flow between these populations may lead to individuals with intermediate body sizes, which may not be adaptive in either population.

A second way outbreeding depression can occur is by the breakdown of biochemical or physiological compatibilities between genes in the different populations. Within local, isolated populations, alleles are selected for their positive, overall effects on the local genetic background. Due to nonadditive gene action, the same genes may have rather different average effects in different genetic backgrounds--hence, the potential evolution of locally coadapted gene complexes.

In other words, individuals from Population A will tend to have genes selected for the quality of combining well with gene combinations common in Population A. However, genes found in Population A will not have been selected for the quality of crossing well with genes common in Population B. Therefore outbreeding can undermine vitality by reducing positive epistasis and/or increasing negative epistasis.

However, it is critical to understand that reduced inbreeding depression in first generation hybrids can, in some circumstances, be strong enough to more than make up for outbreeding depression. Because of this and because of the uniformity and predictable outcome of a first generation hybrid (F1 hybrid) farmers keep purebred strains for the purpose of outcrossing. Crossing the hybrids will give unpredictable outcomes and outbreeding depression will remain or worsen so that is not common practice.

As a general rule of thumb, hybrid vigor (another way of saying a reduction of inbreeding depression) is strongest in first generation hybrids and gets weaker over time. In contrast, outbreeding depression can be relatively weak in the first generation. But outside the context of ruthless selective pressure, outbreeding depression will increase in power through the further generations as co-adapted gene complexes are broken apart without the forging of new co-adapted gene complexes to take their place.

It is important to keep in mind that these two mechanisms of outbreeding depression can be operating at the same time. However, determining which mechanism is more important in a particular population is very difficult.

point#2 Inbreeding depression

Inbreeding depression is reduced fitness in a given population as a result of breeding of related individuals. Breeding between closely related individuals, called inbreeding, results in more recessive deleterious traits manifesting themselves. The more closely related the breeding pair is, the more homozygous deleterious genes the offspring may have, resulting in very unfit individuals. Another mechanism responsible is overdominance of heterozygous alleles leading to a reduction in the fitness of a population with many homozygous genotypes, even if they are not deleterious. Currently it is not known which of the two mechanisms is more important. In general, populations with more genetic variation do not suffer from inbreeding depression. Inbreeding depression is often the result of a population bottleneck. Inbreeding depression seems to be present in most groups of organisms, but is perhaps most important in hermaphroditic species, most prominently in plants. The majority of plants are hermaphroditic and thus are capable of the most severe degree of inbreeding.

Natural selection cannot effectively remove all deleterious recessive genes from a population for several reasons. First, deleterious genes arise constantly through mutation within a population. Second, in a population where inbreeding occurs frequently, most offspring will have some deleterious traits, so few will be more fit for survival than the others. It should be noted, though, that different deleterious traits are extremely unlikely to equally affect reproduction. An especially disadvantageous recessive trait expressed in a homozygous recessive individual is likely to eliminate itself, naturally limiting the expression of its phenotype. Third, recessive deleterious alleles will be "masked" by heterozygosity, and so heterozygotes will not be selected against (assuming dominance).

Introducing new genes from a different population can reverse inbreeding depression. Different populations have different deleterious traits, and therefore will not result in homozygosity in most loci in the offspring. This is known as outbreeding enhancement, practiced by conservation managers and zoo captive breeders to prevent homozygosity. However, intermixing two different populations may give rise to unfit polygenic traits in outbreeding depression.

http://en.wikipedia.org/wiki/Inbreeding_depression

 

[Eric Adrignola]

The florida veileds may come from a small gene pool, but they are no threat to the hobby. Natural selection is doing it's work. Any animals that make it to adulthood have been filtered and checked and tested by a far more rigorous set of demands than most (if not all) breeders are willing to undertake.

It seems that the wild population of veileds in Florida has had a dramatic increase in the average size of individuals in a short period of time.

You coudl take a borther and sister, mate them, subject the offspring to selective forces, and have perfectly viable, strong populations in a short time.

At the same time, you can take a large group of unrelated individuals, have nearly ALL the offspring reproduce, and in time, reduce the overall fitness of the population dramatically.

 

[chequepoint]

By threat to the hobby, i meant politically. Which is a whole other discussion, but they are a shining example of the negligence that this hobby is known for, so its really not the best idea to hold them up in any sort of positive light.

The florida veileds may come from a small gene pool, but they are no threat to the hobby. Natural selection is doing it's work. Any animals that make it to adulthood have been filtered and checked and tested by a far more rigorous set of demands than most (if not all) breeders are willing to undertake.

It seems that the wild population of veileds in Florida has had a dramatic increase in the average size of individuals in a short period of time.

You coudl take a borther and sister, mate them, subject the offspring to selective forces, and have perfectly viable, strong populations in a short time.

At the same time, you can take a large group of unrelated individuals, have nearly ALL the offspring reproduce, and in time, reduce the overall fitness of the population dramatically.

 

[Eric Adrignola]

I agree with that. While I do not really believe there is much that will be harmed (ecologically speaking) from their introduction ot Florida, it certainly does not look very good. It makes people in our hobby look like the kind of people that care nothing for the environment. It makes us seem like we can't even control a tree-lizard, let alone a venoumous snake! So how are we to be trusted?

It's justification to those who wish to impose more controlling laws.

 

[summoner12]

By threat to the hobby, i meant politically. Which is a whole other discussion, but they are a shining example of the negligence that this hobby is known for, so its really not the best idea to hold them up in any sort of positive light.

you took the words right out of my mouth except the bit about not giving them any sort of positive light.... I agree with you but not 100% . We can learn a bit about them being out in the wild... but I do agree it isn't something to be very proud of. I would like to see some out in the wild though i would be very need to watch them... just doing their daily routine out in the wild.