# Line Breeding To Maintain Traits



## pl259

First let me apologize before hand if I don't use the terms correctly. 

I'm not talking about hybrids, creating new morphs/patterns. I'm talking about assisted mate selection. 

As a hobby, more times than not, we toss any pair into a tank and let them breed. A selection limited, forced situation. Is this the best approach?

When I have active breeding of a species, I'll hold back some amount of froglets and raise them to subadults in order to prepare for the next generation. From this group, I'll select a couple pairs or group that I feel best represent the species. Strong calls, good coloration/patterning, size, etc. Not trying to create something new here, or propagate some unusual trait.

Is this a bad approach? Does it not attempt to provide some amount of pre-selection, to an otherwise selectionless approach to breeding?


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## mainbutter

That is a wonderful approach. Selective breeding is all important to herpetoculture, I have NEVER "tossed ANY pair together" of any species that I have bred. I am extremely selective in individuals that I purchase, usually with the particular intention of choosing future mates. From those pairings, I tend to hold back the best 1-5% I ever produce, and future selection and plans for pairing begins.

This is easier with certain species of animals than others, I certainly don't know if it's possible to acquire an eye for picking out the best froglets before they are old enough to start being sold, but with the snakes and geckos I keep it tends to be fairly easy to know which ones I like the looks of best.


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## Pumilo

mainbutter said:


> That is a wonderful approach. Selective breeding is all important to herpetoculture, I have NEVER "tossed ANY pair together" of any species that I have bred. I am extremely selective in individuals that I purchase, usually with the particular intention of choosing future mates. From those pairings, I tend to hold back the best 1-5% I ever produce, and future selection and plans for pairing begins.
> 
> This is easier with certain species of animals than others, I certainly don't know if it's possible to acquire an eye for picking out the best froglets before they are old enough to start being sold, but with the snakes and geckos I keep it tends to be fairly easy to know which ones I like the looks of best.


I'm afraid I disagree. This is line breeding for specific traits. We should be attempting to keep our gene pools as natural as possible, not increasing any one coloration or trait. Here is an example. If I take a Varadero with a high orange pattern and mate it with another I have deliberately chosen as another high orange pattern, I am now Selectively Breeding (often miscalled Line Breeding) for an orange pattern. Instead, I should be attempting to keep ALL the natural genes in the line. So what I should ideally do is to select a Varadero mate with a lot of Blue Lightning throughout his back to mate with my High Orange girl. In this we we are at least attempting to keep the genes as natural as possible and will perhaps keep the wide variety of patterns that Varadero are known for.


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## Allyn Loring

Isn't beauty in the eye of the beholder?Isn't any and all breeding manipulation on our part(in the confines of OUR enclosures)?


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## stemcellular

One thing to consider that is many of the offspring that we raise artificially face little (if any) selective pressure. Therefore, frogs that would normally succumb to predation due to high color/low color, size, speed, deformities, etc. are kept alive in captivity and bred back into the gene pool. There is also some evidence to suggest that the females of certain species select based on phenotypic preference (ie. some prefer more color, others less color, etc). While I understand the points above, by rearing frogs in captivity we somewhat negate any real attempt to "keep the lines pure" in a wild type sense. While my approach is usually to just toss frogs in together and see who makes it...who breeds...etc. I don't have a problem with Eric's approach.


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## Ed

Actually what this is, is artificial selection toward a breed standard. Ideally, the mate choice should be to frogs that are as distantly related to that frog within a known population* (this is not hybrid or crossbreeding morphs) however for most of the populations the relatedness** of any frog to another frog of the same population is unknown. Often a person will obtain frogs of the same population from another hobbyist or breeder but this doesn't indicate relatedness as those breeders could have had the same parents or grandparents. If relatedness is unknown then the breeders should actually be chosen randomly. By choosing the breeders people are selecting frogs for a number of traits which due to the directed selection cause the loss of genetic diversity and eventually the accumulation of negative allelles.


*population is defined as group of the same morph or in the case of some of the visually attributed pumilio the same import

** excluding frogs tracked using TWI ASN program or Robb Melancon's Frog Trax.


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## Boondoggle

As regards the OP, it depends on ones goals. If, like mainbutter, your goal is to isolate particular genetics that result in specific extremes in order to produce an animal that is visually unusual/stunning, then line breeding is how it's done through most of herpetoculture.

If you, some of the other posters, are more interested in preserving as diverse a pool of the original genetic possibilities, then line breeding doesn't really serve that purpose.

It seems, unlike snake or gecko keepers, more PDF hobbyists fall in the latter group.

I would just like to point out the term "best frog" is not synonymous with the idea of a "visually appealing" frog. Line breeding eliminates alleles from the gene pool, and not just ones related to color/pattern. It makes me think of the production/mortality rates between heavily morphed boids and their common counterparts.


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## Allyn Loring

Hope Eric does not think I'm jumping on him ,I too am guilty of selecting certain patterns in certain morphs that appeal to my own individual eye .For me it doesn't smack of right or wrong ,just bias, on my own part!


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## MonarchzMan

If the aim is to keep the gene pool as static as possible, then mates must be random. While Ray is right in that there are a number of frogs in the hobby that likely would not make it in the wild, in a program to keep the gene pool static, this shouldn't matter because they should represent a portion of the population in the wild that also would not be fit to survive. If you do anything other than random pairings from distantly or unrelated pairs, then you're going to be having some sort of selection on the frogs.


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## pl259

Perhaps the better way to think about it, is on the negative side. Where the choice is more about which ones NOT to include in the pool of candidate breeders. 

I agree a certain amount of randomness is needed in the process. But after working with and observing many of these species for a few years now, I believe mate selection is a large part of their natural process. It's not just all about rolling the dice.

As hobbiests, without some well intended external selection, we're eliminating a large part of that natural, mate selection process, if not all of it. With limited populations in small enclosures, it's "If you can't be with the one you love, love the one you're with" for many species. 

Within this hobby, the general structure of our seperate collections and populations, does not follow the natural processes occuring in the wild. IMO, we need to do more than simple random selection.


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## gary1218

pl259 said:


> "If you can't be with the one you love, love the one you're with"


Stephen Stills, 1970.....................What do I win


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## MonarchzMan

pl259 said:


> Perhaps the better way to think about it, is on the negative side. Where the choice is more about which ones NOT to include in the pool of candidate breeders.
> 
> I agree a certain amount of randomness is needed in the process. But after working with and observing many of these species for a few years now, I believe mate selection is a large part of their natural process. It's not just all about rolling the dice.
> 
> As hobbiests, without some well intended external selection, we're eliminating a large part of that natural, mate selection process, if not all of it. With limited populations in small enclosures, it's "If you can't be with the one you love, love the one you're with" for many species.
> 
> Within this hobby, the general structure of our seperate collections and populations, does not follow the natural processes occuring in the wild. IMO, we need to do more than simple random selection.


There definitely is mate selection naturally, but the problem with that is that we don't know what the mate selection criteria is. And it is possible that it could change as a result of the environment. So a given female may choose a male in the wild that she may not choose when in captivity, for whatever reason. We don't know what is natural for these populations, so we don't want to try to mimic natural conditions in a mating environment.

Thus it's best to keep everything random.


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## pl259

gary1218 said:


> Stephen Stills, 1970.....................What do I win


My respect... but you already had that!


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## pl259

MonarchzMan said:


> There definitely is mate selection naturally, but the problem with that is that we don't know what the mate selection criteria is. And it is possible that it could change as a result of the environment. So a given female may choose a male in the wild that she may not choose when in captivity, for whatever reason. We don't know what is natural for these populations, so we don't want to try to mimic natural conditions in a mating environment.
> 
> Thus it's best to keep everything random.


I respectfully disagree. Just because we can't mimick the natural mate selection process exactly, doesn't mean we should abandon reasonable attempts to try. Especially when the offered alternative, a random only process, whether adequate or not, isn't truely acheivable within our hobby.


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## earthfrog

Ed said:


> By choosing the breeders people are selecting frogs for a number of traits which due to the directed selection cause the loss of genetic diversity and eventually the accumulation of negative allelles.


To clarify---the frogs develop a greater likelihood of having a harmful mutation over time due to an increase in defective components of genes. By limiting the gene choices available through selecting for specific colors or external traits, you increase the chance that you will encourage a sickly line of frogs over time. It's like having less and less good parts from which to build an engine---after hit and miss from patching it together with poor parts, it's not going to last that long. 
This might manifest in many ways we don't yet know, but a prominent example is the huge amount of health problems in purebred dogs who were not screened for genetic defects before being bred to one another, and passed on things like hip and knee dysplasia, blindness and extreme aggression (even in young puppies). 

I really don't want that for these frogs. There's no way to undo that damage. 
I tend to get a large group and let the frogs choose their own mates. Isn't that the way to do it?


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## Ed

pl259 said:


> Perhaps the better way to think about it, is on the negative side. Where the choice is more about which ones NOT to include in the pool of candidate breeders.
> 
> I agree a certain amount of randomness is needed in the process. But after working with and observing many of these species for a few years now, I believe mate selection is a large part of their natural process. It's not just all about rolling the dice.
> 
> As hobbiests, without some well intended external selection, we're eliminating a large part of that natural, mate selection process, if not all of it. With limited populations in small enclosures, it's "If you can't be with the one you love, love the one you're with" for many species.
> 
> Within this hobby, the general structure of our seperate collections and populations, does not follow the natural processes occuring in the wild. IMO, we need to do more than simple random selection.


There is a good bit of data on how to manage populations in captivity and a lot of it is referenced in the ASN program (and a bunch has been cited here as well) 

Ideally one would have a population with a diverse and known parentage (back to the original wild caught founders) and the population is managed through a taxon management plan where the genetic representation of each founder is managed and kept from being lost. With this sort of management genetic diversity and maximal longevity of the population in captivity can be sustained. With a founder population of 50 animals, greater than 90% of the genetic diversity can be sustained for more than 200 years with this method. 

If the population is from a group of unknown founders (number and contribution to the population) and the frogs cannot be maintained as a colony (which allows for mate selection) then mate choice should be by random determination as this prevents bias whether conscious or unconscious. 

The whole goal of enabling a population for sustainability is to manage it for maximal genetic variation, even providing mate choice doesn't mean that will occur as you don't know the contributions to the population from the founder and subsequent generations.


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## Rain_Frog

It's a slippery slope.

Side 1 of the coin: What we may call "healthy or fit" in captivity may not be successful in the wild. I've noticed a lot of people think the healthiest frog is the biggest, fattest individual when in reality, that's not always a good way of determining the health. Look at our domestic livestock breeds that have been chosen for "the biggest fattest" individual and now, double breasted white tom turkeys cannot mate naturally now.

My dominant and breeder male pulchra and madagascariensis are the thinnest, most active, and smallest. In fact, my dominant male madagascariensis is very aggressive to the largest, fattest male in the tank and always wins in a dispute. However, there is no way for me to know if this is an adaption to captive life or what would perpetuate in wild populations, but I'm just using it for an example that "the biggest, fattest frog" isn't always reliable.

I have a pair of mantellas that the male has a short femur but his single offspring is normal.

Side 2 of the coin: Nutrition influences size and other factors, so its possible that a smaller frog may have had poor nutrition as a tadpole or froglet. In this case, it can somewhat be an indicator of health, but my question is, how does it influence the long term health of the frog? 

Back before I learned about the "third wheel," I kept 2 male and 1 female cobalt together. The dominant male bullied the weaker male and it took me a long time to get him to recover. He's always been shier, more nervous, and eats much less than the other 2. But he calls more. Once I started to use a retinol supplement, he started to put weight on and activity and appetite levels increased.


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## Rain_Frog

> If the population is from a group of unknown founders (number and contribution to the population) and the frogs cannot be maintained as a colony (which allows for mate selection) then mate choice should be by random determination as this prevents bias whether conscious or unconscious.


Most of our locales are from small populations, correct? I'm curious if "inbreeding" is as serious as people cite since I would think that frogs from small locales would already have gone through a bottleneck phase and purge negative alleles from the gene pool.

Of course, you can fit thousands of frogs in a square mile and only a few megafauna in the same location...


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## MonarchzMan

pl259 said:


> I respectfully disagree. Just because we can't mimick the natural mate selection process exactly, doesn't mean we should abandon reasonable attempts to try. Especially when the offered alternative, a random only process, whether adequate or not, isn't truely acheivable within our hobby.


Why wouldn't a random process be achievable within the hobby? In an ideal world, we would know parentage, but we don't. So it would seem to me that the best option is to get as random as possible. Random is random. Unless a particular breeder maintains separate, completely unrelated lines, get a male from one breeder and a female from another. It's not that difficult to be random.

If you try to mimic selection, eventually traits will be lost and the population in captivity won't truly reflect wild populations.


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## pl259

Ed said:


> ...managed through a taxon management plan where the genetic representation of each founder is managed and kept from being lost...


Would not selecting offspring that closely matched the traits of the parents, work towards acheiving this?



> If the population is from a group of unknown founders (number and contribution to the population) and the frogs cannot be maintained as a colony (which allows for mate selection) then mate choice should be by random determination as this prevents bias whether conscious or unconscious.


Mate selection is a successful, biased process. Doesn't removing that bias effectively water down the genetic pool and lessen those numbers of animals that more closely match the original founders? I agree we should maintain genetic variation beyond this, but wouldn't it be better to err on the side of maintaining the genetics of a proven success, rather than gambling on the roll of the dice? And further, doesn't the quote assume then that the husbandry and conditions we keep them in, are also unbiased, relative to their natural habitat? I don't feel that's the case, and keeper selection, again if done properly, could actually work to offset the bias that is occurring in our captive bred population.



> The whole goal of enabling a population for sustainability is to manage it for maximal genetic variation, even providing mate choice doesn't mean that will occur as you don't know the contributions to the population from the founder and subsequent generations.


I understand this goal, but I'm not sure I agree it and a random implementation, best applies to our captive populations. And I'm no where near expert enough to offer a well thought out counter to it. I would think though, that selectively maintaining the traits of the line/original WC specimens, combined with periodically refreshing captive bred stock with new WC animals, would be a least one better approach.


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## pl259

MonarchzMan said:


> Why wouldn't a random process be achievable within the hobby? In an ideal world, we would know parentage, but we don't. So it would seem to me that the best option is to get as random as possible. Random is random. Unless a particular breeder maintains separate, completely unrelated lines, get a male from one breeder and a female from another. It's not that difficult to be random.


My comment is more a statement on our current culture and whether as a group, we have the means to change. I agree that if we, as a hobby, did a better job of breeding unrelated pairs, the process would be more random. But that's not how the bulk of the breeding pairs are established. Perhaps we need to adopt more swapping of stock.



> If you try to mimic selection, eventually traits will be lost and the population in captivity won't truly reflect wild populations.


And a random process prevents this? Is random really better in this regard?


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## MonarchzMan

pl259 said:


> Would not selecting offspring that closely matched the traits of the parents, work towards acheiving this?


Nope, selection means that you are gradually working to weed out particular traits, which would have been represented in the founder stock. So selecting for traits would mean you're deviating from the founder stock.



> Mate selection is a successful, biased process. Doesn't removing that bias effectively water down the genetic pool and lessen those numbers of animals that more closely match the original founders? I agree we should maintain genetic variation beyond this, but wouldn't it be better to err on the side of maintaining the genetics of a proven success, rather than gambling on the roll of the dice? And further, doesn't the quote assume then that the husbandry and conditions we keep them in, are also unbiased, relative to their natural habitat? I don't feel that's the case, and keeper selection, again if done properly, could actually work to offset the bias that is occurring in our captive bred population.


Say a trait is found 10% of the time in the founder stock (let's say no spots, which means spots is found 90% of the time). If you breed two spotted frogs together and get a number of spotted offspring and a couple unspotted offspring. If you select those spotted offspring to breed, then you're changing that ratio, and reducing the amount of genetic variation in the breeding colony. If there is no selection, there is no way that the unspotted allele frequency will go beyond 10%, so you wouldn't be watering down the genetic pool.

As for husbandry and conditions are unbiased, it's not possible to get completely unbiased, it's true, but it all comes down to a female frog breeding with a male frog. If there is no choice allowed in the pairing, then it doesn't matter what the rearing conditions are, right?



> I understand this goal, but I'm not sure I agree it and a random implementation, best applies to our captive populations. And I'm no where near expert enough to offer a well thought out counter to it. I would think though, that selectively maintaining the traits of the line/original WC specimens, combined with periodically refreshing captive bred stock with new WC animals, would be a least one better approach.


Actually, if done properly, you wouldn't have to refresh with WC animals. But selecting particular traits is going to result in the loss of genetic diversity, not maintenance of it.

It all really is based off of the Hardy-Weinberg equilibrium, which is a set of conditions for evolution not to occur, which is generally the goal of captive programs because we do not know what selective pressures act on these populations in the wild, so a captive population should basically represent a snapshot of what we saw at the time of import.



> My comment is more a statement on our current culture and whether as a group, we have the means to change. I agree that if we, as a hobby, did a better job of breeding unrelated pairs, the process would be more random. But that's not how the bulk of the breeding pairs are established. Perhaps we need to adopt more swapping of stock.


This is true, but TWI has protocols up for starting this process. I would say that the bulk of people setting up breeding pairs are not like you or I in wanting to maintain genetic diversity in the population.



> And a random process prevents this? Is random really better in this regard?


See above. If done at random, then there is no way that a trait could increase or decrease in a population aside from mutation, which is unavoidable.


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## Boondoggle

pl259 said:


> I respectfully disagree. Just because we can't mimick the natural mate selection process exactly, doesn't mean we should abandon reasonable attempts to try. Especially when the offered alternative, a random only process, whether adequate or not, isn't truely acheivable within our hobby.


That presupposes that we understand enough of the natural mate selection process to duplicate it. We make some assumptions about mate selection (size? Dominance? Robustness?) but a little knowledge can be a dangerous thing. Sneaker males, anyone?

If you take that approach and do it perfectly, you could replicate a specific animals current genetic "map". Anything short of that and you begin throwing out genetic material. Ed mentions that in a specific case 90% of the genetics could be preserved over a very long period of time by randomly pairing animals. Do you think that we understand PDF mate selection enough to even remotely approach that number?

I'm not saying anything is evil about line breeding per se. I own Black Sauls and I have put together unusually orange leucs on purpose before. The fact remains though, whether we line breed for specific traits or in an effort to "second guess" what the frogs natural preference would have been, if we all did this with all our frogs we would lose a lot of genetic material.


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## Ed

Rain_Frog said:


> Most of our locales are from small populations, correct? I'm curious if "inbreeding" is as serious as people cite since I would think that frogs from small locales would already have gone through a bottleneck phase and purge negative alleles from the gene pool.
> 
> Of course, you can fit thousands of frogs in a square mile and only a few megafauna in the same location...


No, this doesn't mean that negative alleles were purged. There can still be negative alleles in the wild population which due to the distribution in the wild populations are expressed infrequently but in a captive population with a few founders, the frequency can shift (as there isn't any pressure that would result in those genes being lethal) resulting in expression at greater frequencies eventually possibly extirpating the population. 
This has/is been seen in populations originating from island enviroments like the Micronesian Kingfisher. 

As a second example, there can still be negative genes which convey a positive survivial advantage in the heterozygous form but results in problems in homozygous form.... an example of this is seen in people who carry the genes for sickle cell anemia. It is a survivial advantage against malaria


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## Ed

pl259 said:


> Would not selecting offspring that closely matched the traits of the parents, work towards acheiving this?


Actually no, this is breeding for conformation. We can see the results of this in a well documented group of animals specifically pure breed dogs. As the population of a breed of dog rise so do the genetic diseases that afflict that population. 
You want to preserve the maximal amount of genetic diversity in the captive population and if you breed solely on conformational basis you lose divesity as you are breeding frogs that are best adapted to the husbandry conditions. This is a loss of genetic variation and probably a loss of histocompatiability complex genes. 




pl259 said:


> Mate selection is a successful, biased process. Doesn't removing that bias effectively water down the genetic pool and lessen those numbers of animals that more closely match the original founders? I agree we should maintain genetic variation beyond this, but wouldn't it be better to err on the side of maintaining the genetics of a proven success, rather than gambling on the roll of the dice? And further, doesn't the quote assume then that the husbandry and conditions we keep them in, are also unbiased, relative to their natural habitat? I don't feel that's the case, and keeper selection, again if done properly, could actually work to offset the bias that is occurring in our captive bred population.


Mate choice would only work if you could correct for maladaption syndrome as males that were more adapted to surviving in captive conditions are going to be more fit and thus more likely to be chosen as mates. Many animals use histocompatiability complexes to affect mate choice but anurans may not.. see for example http://www.biosci.utexas.edu/ib/faculty/ryan/pubs/1992AmNat139 S4.pdf

As a further complication, you would have to be able to give the females access to a group of males that represent the widest variety of alleles representing the population (and still could have issues with maladaption).


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## pl259

Thanks everyone for the replies. 

Twice now I've written replies that took too long to write, and when the system made me log back in, the messages were lost. Very frustrating. 

When I get over it, I'll try again and respond to the comments.


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## SmackoftheGods

pl259 said:


> As hobbiests, without some well intended external selection, we're eliminating a large part of that natural, mate selection process, if not all of it. With limited populations in small enclosures, it's "If you can't be with the one you love, love the one you're with" for many species.
> 
> Within this hobby, the general structure of our seperate collections and populations, does not follow the natural processes occuring in the wild. IMO, we need to do more than simple random selection.


Why not keep larger enclosures for groups of frogs (certain frogs that can be kept in groups)? Then instead of selecting a single male and a single female and saying "there you go, just do it" you're allowing them (at least on _some_ level) to choose their partners? It's not an ideal solution, it's not going to fix everything, but it's better than selecting a pair and keeping them together forever....

Edit: I forgot that this was three pages long and it looks like Ed beat me to this idea (different wording, though)


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## pl259

Agreed. Larger enclosures with larger groups, is a step in the right direction.


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## Ed

pl259 said:


> Thanks everyone for the replies.
> 
> Twice now I've written replies that took too long to write, and when the system made me log back in, the messages were lost. Very frustrating.
> 
> When I get over it, I'll try again and respond to the comments.


I have had this happen to me more times than I want to think about and it is enormously frustrating particularly when I've looked up the pdfs to support the argument. 

Ed


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## Scott Richardson

I really believe for the most part we are basically line breeding now. 

When I see proven pairs for sell, the majority of them are for example "Nabors line" 
Great, we can trace the line back to Patricks records. 

If I was breeding Blue Auratus (which I am not) I think I would rather have a male from Nabors line, a female from Sean, and a female from EU stock. 

Yes, I am breeding across lines, but if my pair are both offspring from the same pair, I would basically be line breeding. since I am breeding offspring together with the same traits from the same pair.


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## Woodsman

Given that the founder populations for the frogs in the hobby were (are) too small to be of any real use in a scientifically-based re-introduction effort (as in, our frogs are not going "back to nature"), perhaps we should focus on those traits in the frogs that best adapt them to permanently living in captivity. The kind of selection pressures in the hobby are probably precisely those pressures that would lead to an adaptation to captivity.

No one else here has said this, but the reality is that we all hold back those frogs in our progeny that we find most attractive for future breeding projects. I know I do. The idea that I would completely randomize my offspring isn't the way that I see my collection. Whether the result of this is "line-breeding", I'm not sure. I am pretty careful to try to find unrelated frogs from different "bloodlines" to pair-up my breeding pairs from. I think that goes farther in maintaining diversity than anything else I do.

A good thread and an important subject, Richard.


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## skylsdale

Scott Richardson said:


> When I see proven pairs for sell, the majority of them are for example "Nabors line"
> Great, we can trace the line back to Patricks records.
> 
> If I was breeding Blue Auratus (which I am not) I think I would rather have a male from Nabors line, a female from Sean, and a female from EU stock.


Exactly...assuming those lines all trace back to being collected from the same wild population. The problem is that people assume a "line" is the same as a "population" and therefore refrain from mixing frogs from different lines. Ideally we _want _to mix/cross progeny from various lines (assuming they are from the same population) in order to increase genetic variability and unrelatedness in our captive frogs.


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## chuckpowell

So what traits lead to adaptation to captivity. What should we look for in breeding our frogs to make them more suitable to captivity? 

I think we need to breed the biggest and most colorful frogs we can of a particular species; large healthy frogs and let the rest die. In the long run it would be best for the hobby. We already know the founding stock for most species (if not all) is small so why keep weak frog and breed weak frogs to the determent of the future of the hobby. 

I know people will cry we can't kill the frogs - then what should we do with them? Most captive breed animals are smaller and less colorful then their wild caught ancestors and its our fault. Our husbandry isn't up to wild standards. We can get them to live longer in captivity but do we get them to live better in captivity?

Best,

Chuck



Woodsman said:


> Given that the founder populations for the frogs in the hobby were (are) too small to be of any real use in a scientifically-based re-introduction effort (as in, our frogs are not going "back to nature"), perhaps we should focus on those traits in the frogs that best adapt them to permanently living in captivity. The kind of selection pressures in the hobby are probably precisely those pressures that would lead to an adaptation to captivity.


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## Ed

chuckpowell said:


> So what traits lead to adaptation to captivity. What should we look for in breeding our frogs to make them more suitable to captivity?
> 
> I think we need to breed the biggest and most colorful frogs we can of a particular species; large healthy frogs and let the rest die. In the long run it would be best for the hobby. We already know the founding stock for most species (if not all) is small so why keep weak frog and breed weak frogs to the determent of the future of the hobby.


 
And when inbreeding depression sets in and results in a population that is unsustainable, then what? There are a lot of examples of how this form of breeding to a standard results in a population full of genetic issues.. we can look at purebred dogs, cats..... By conducting the breeding in this manner you are destroying the genetic variation that allows for a healthy frog. 

In addition, genetically selecting for the "most fit" can easily result in animals that lose the size or the behaviors that make them interesting to many of us.. that of parental behaviors. As a counter example, it is probable that husbandry is a large part of the issue. For example, due to the high number of frogs that are kept in "optimized" conditions for reproduction, resources are readily diverted from growth into breeding at which point, growth slows. There is a high demand to breed the frogs so frogs that reached maturity earlier would be at an advantage over frogs that reached maturity later in captivity as the general practice is pull and artificially rear the eggs. Larger amphibians in a number of genera tend to not only produce more eggs but produce larger better supplied eggs.. this advantage doesn't occur in captive populations as small metamorphs are able to use compensatory growth to reach breeding age so there isn't any advantage in larger frogs anymore. This is even before we start looking at phenotypical plasticity (which can become a fixed trait through artificial selection), or epigenetics... 

There are a lot of reasons to not utilize a breeding standard and not a lot of reason to do so... unless you are looking for the frog that is the equivalent of a cocker spaniel or german shepard with all of the genetic disease issues. 

Ed


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## chuckpowell

Thanks for your reply Ed. I'm not a biologists. I'm a paleontologists and work with dirt and long dead things - my education is all in geology. But your answer doesn't seem to help with what we need to look for to produce the best animals. I also believe husbandry is a very big part of keeping and producing "good" frogs and a part that we don't know well enough about and we aren't satisfying. Still your answer implies there isn't anything we can look for to help us produce "good" frogs. Or am I reading it wrong? If not what do we do to produce good quality frogs over long periods of time? 

Best,

Chuck



Ed said:


> And when inbreeding depression sets in and results in a population that is unsustainable, then what? There are a lot of examples of how this form of breeding to a standard results in a population full of genetic issues.. we can look at purebred dogs, cats..... By conducting the breeding in this manner you are destroying the genetic variation that allows for a healthy frog.
> 
> In addition, genetically selecting for the "most fit" can easily result in animals that lose the size or the behaviors that make them interesting to many of us.. that of parental behaviors. As a counter example, it is probable that husbandry is a large part of the issue. For example, due to the high number of frogs that are kept in "optimized" conditions for reproduction, resources are readily diverted from growth into breeding at which point, growth slows. There is a high demand to breed the frogs so frogs that reached maturity earlier would be at an advantage over frogs that reached maturity later in captivity as the general practice is pull and artificially rear the eggs. Larger amphibians in a number of genera tend to not only produce more eggs but produce larger better supplied eggs.. this advantage doesn't occur in captive populations as small metamorphs are able to use compensatory growth to reach breeding age so there isn't any advantage in larger frogs anymore. This is even before we start looking at phenotypical plasticity (which can become a fixed trait through artificial selection), or epigenetics...
> 
> There are a lot of reasons to not utilize a breeding standard and not a lot of reason to do so... unless you are looking for the frog that is the equivalent of a cocker spaniel or german shepard with all of the genetic disease issues.
> 
> Ed


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## skylsdale

chuckpowell said:


> But your answer doesn't seem to help with what we need to look for to produce the best animals. I also believe husbandry is a very big part of keeping and producing "good" frogs and a part that we don't know well enough about and we aren't satisfying. Still your answer implies there isn't anything we can look for to help us produce "good" frogs. Or am I reading it wrong? If not what do we do to produce good quality frogs over long periods of time?


Chuck, it might help if you define what you mean by a "good" frog. 

If I were to talk to a local fish hatchery employee or director, their definition of a "good" fish (most of which are for sport fishing at this point) would be drastically different from what a fisheries biologist would define as a "good" fish. Hatcheries are becoming a classic example of animals being shaped to survive in captivity: more than 90%--perhaps even as much as 98%--of hatchery fish released into the wild don't survive their first year there. Not only do they not survive in the wild streams (their predator-less rearing ponds keep them naive about certain survival and feeding behaviors), but their enhanced aggression (from being raised with copious numbers of other fish competing for the same resources) pushes out native, previously established fish. Sport fisherman love the beefed up aggressive fish and, at least here in the PNW, are pushing for the stocking of things like "triploid" trout.

Which is better...the bigger, beefier fish? Or the sleeker, more reclusive wild fish? The former would certainly look better mounted on a wall...but the latter is what first drew my fascination. Snorkeling in a cold mountain river and seeing how native trout and salmon feed and inhabit their stream environment is a whole different experience from seeing a fat, overfed fish lumbering around a cement stock tank.

In keeping frogs in captivity, for me personally, I want to attempt to 'preserve' a slice of that magic wildness within the confines of a glass box...but in a way that hopefully mimics, in as many ways as possible, their natural habitat so as to preserve as much of that wildness as I can. In some instances this may result in nice big, brightly-colored specimens. In others it may mean including what, to me, seems to be a less than stellar specimen...but one that likely contains recessive traits and genes that aren't expressed and could still be beneficial for the captive population as a whole.


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## SmackoftheGods

chuckpowell said:


> Thanks for your reply Ed. I'm not a biologists. I'm a paleontologists and work with dirt and long dead things - my education is all in geology. But your answer doesn't seem to help with what we need to look for to produce the best animals. I also believe husbandry is a very big part of keeping and producing "good" frogs and a part that we don't know well enough about and we aren't satisfying. Still your answer implies there isn't anything we can look for to help us produce "good" frogs. Or am I reading it wrong? If not what do we do to produce good quality frogs over long periods of time?
> 
> Best,
> 
> Chuck


Seems to me that the issue with a lot of hobbyists is that they have some sort of preconceived notion of what a "good frog" is. A bigger frog must mean that it acquired/absorbed nutrients better. A bolder frog is a better display animal. A more (or more uniquely) colored frog is more appealing to they eye. I'm personally inclined to think that it has something to do with the human tendency to anthropomorphize. Humans who keep and maintain a tan seem to have a "healthy" look about them. Bigger, stronger humans with bigger more well defined muscles look healthier. Seems like the traits that we believe are considered best for human beings is what we look for in our frogs.

While I don't think that Ed is trying to argue that these larger, more colorful frogs are bad to breed, it doesn't seem like we should _only_ breed these frogs. I'm not saying we should breed ALL frogs, some with deformities (fifth legs, SLS, etc) should not be bred. But who's to say that a bigger frog is _better_ than a smaller frog? Strictly as a display animal you may be right, a bigger animal is better for that purpose. But there's little evidence that a bigger animal is more likely to make it or pass on its genes than a smaller frog (I'm using size as an example to make a generalization about a larger picture, I don't really want to go over every detail that hobbyists look for in their frogs).

So no, truly weak frogs (those frogs that have strong difficulties feeding themselves, for instance) probably shouldn't be coddled. But just because a frog doesn't meet the hobbyists standard of the "ideal specimen" of a particular species/morph hardly means that it should be left to die. This is not an argument about the morality of killing frogs, but one that ties in to the inbreeding depression that Ed refers to. When you select certain features that make for the ideal frog, you're artifically weeding out certain genes from the captive population's gene pool.

That's why, when I order my frogs, I request "phenotypic variation." I try not to specify what I'm looking in my individual frogs, just that I want them to vary (size, shape, color...). Breeding the same size, color, pattern, shape frogs with one another seems to increase the likelihood of inbreeding depression (at least, seems to increase said likelihood from my understanding of the issue).

All of that is a long way of answering your question when a nice summary could easily do: instead of looking for "good" or "ideal" frogs, look for frogs that complement one another in their diversity from one another, rather than weeding out those traits that you find less than ideal.


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## chuckpowell

Ok, so let start a discussion on what we should look for in frogs for our hobby. What is a "good" frog in relation to keeping them in terrariums in our homes. These animals will never be returned to the wild - what we do to them and how we keep them prevent this. 

When I think big, colorful frog I think of what I see come in from the wild, what has been selected in the wild as "the best." This has nothing to do with color pattern which are always diverse. But overall the frogs brought in from the wild are larger and more colorful than what we produce in our glass tanks, with few exceptions. 

Preserving a slice of the 'magic wildness' while admirable seems, to me, unrealistic. As soon as the frogs breed in captivity they are being adapted to the environment in which we put them. So we should figure out what we want in our frogs, and more importantly to produce frogs that will do well in captivity and therefore be around in something near what they look like in the wild some 20, 30, 40 years from now. So far we seem to have failed at this - captive breed D. azureus are now commonly half the size of their wild caught ancestors and the colors while still beautiful don't have the .... intensity of their predecessors. 

Best,

Chuck




skylsdale said:


> Chuck, it might help if you define what you mean by a "good" frog.
> 
> If I were to talk to a local fish hatchery employee or director, their definition of a "good" fish (most of which are for sport fishing at this point) would be drastically different from what a fisheries biologist would define as a "good" fish. Hatcheries are becoming a classic example of animals being shaped to survive in captivity: more than 90%--perhaps even as much as 98%--of hatchery fish released into the wild don't survive their first year there. Not only do they not survive in the wild streams (their predator-less rearing ponds keep them naive about certain survival and feeding behaviors), but their enhanced aggression (from being raised with copious numbers of other fish competing for the same resources) pushes out native, previously established fish. Sport fisherman love the beefed up aggressive fish and, at least here in the PNW, are pushing for the stocking of things like "triploid" trout.
> 
> Which is better...the bigger, beefier fish? Or the sleeker, more reclusive wild fish? The former would certainly look better mounted on a wall...but the latter is what first drew my fascination. Snorkeling in a cold mountain river and seeing how native trout and salmon feed and inhabit their stream environment is a whole different experience from seeing a fat, overfed fish lumbering around a cement stock tank.
> 
> In keeping frogs in captivity, for me personally, I want to attempt to 'preserve' a slice of that magic wildness within the confines of a glass box...but in a way that hopefully mimics, in as many ways as possible, their natural habitat so as to preserve as much of that wildness as I can. In some instances this may result in nice big, brightly-colored specimens. In others it may mean including what, to me, seems to be a less than stellar specimen...but one that likely contains recessive traits and genes that aren't expressed and could still be beneficial for the captive population as a whole.


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## Ed

skylsdale said:


> If I were to talk to a local fish hatchery employee or director, their definition of a "good" fish (most of which are for sport fishing at this point) would be drastically different from what a fisheries biologist would define as a "good" fish. Hatcheries are becoming a classic example of animals being shaped to survive in captivity: more than 90%--perhaps even as much as 98%--of hatchery fish released into the wild don't survive their first year there.


 
And that 2% that does survive to breed with the local populations often passes along traits that reduce fitness of the overall population of that type of fish.


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## Ed

chuckpowell said:


> \
> When I think big, colorful frog I think of what I see come in from the wild, what has been selected in the wild as "the best." This has nothing to do with color pattern which are always diverse. But overall the frogs brought in from the wild are larger and more colorful than what we produce in our glass tanks, with few exceptions.
> 
> Preserving a slice of the 'magic wildness' while admirable seems, to me, unrealistic. As soon as the frogs breed in captivity they are being adapted to the environment in which we put them. So we should figure out what we want in our frogs, and more importantly to produce frogs that will do well in captivity and therefore be around in something near what they look like in the wild some 20, 30, 40 years from now. So far we seem to have failed at this - captive breed D. azureus are now commonly half the size of their wild caught ancestors and the colors while still beautiful don't have the .... intensity of their predecessors.
> 
> Best,
> 
> Chuck


Hi Chuck,

Lets see if I can answer this without being overly verbose (I have doubts..) 

Anytime a group of animals is brought into captivity from the wild, some are going to die without ever becoming established, this is often called maladaption syndrome. So in effect the population is starting off on the wrong foot right away. 

A lot of people attempt to compare captive animals with the wild populations based on genetics but even though this is with the same animals, it is an apples and oranges argument. The reason for this is because the habitat and feeding structure is very different in captive populations. Wild populations are not held in optimized conditions for reproduction 24/7 until they die. The non-breeding periods are significant in wild populations and during those periods, metabolic resources are not being used for breeding and can instead be used for growth. There is a large body of literature on the impacts of reproduction and growth in frogs. As one example of a significant body of literature see SpringerLink - Oecologia, Volume 78, Number 2 (sorry no free pdf). 

As a further complication, we are still figuring out the nutritional needs of the frogs with the understanding that beta carotene is poorly converted to retinol in anurans and that other carotenoids with pro-vitamin A activity need to be used along with some level of retinyl acetate or palminate to prevent hypovitaminosis of A. It is known that in other vertebrates, insufficient vitamin A (particularly in juveniles) can reduce growth rates by 30% or more so this can be another reason that we see smaller adults in captivity. 

Along these lines as well, ovulation is triggered by fat reserves and captive frogs tend to be obese and kept that way as a "sign of health". This can easily result in the females ovulating before all of the needed nutrition for the eggs has been sequestered resulting in embryos that are deficient in needed nutrients from the start. It can also reduce growth as it is pulling resources from growth to provide nutrients to the eggs. 

Another issue, we see discussed a lot is color yet with the exception of metallic colors and blues, color is highly impacted by carotenoid diversity in the diet. Most of the supplements on the market do not supply vitamin A as a type retinol but beta carotene and beta carotene is often the only carotenoid in the supplements. The main dietary food items fed to the frogs are also often significantly lacking in carotenoids.. The last several years has also shown improvements in the understanding of the carotenoid needs of the frogs and the first steps to address it through the use of supplements. Often people look at a possible food item like paprika and applies a version of the Doctrine of Signatures, thinking that it will increase red coloration in the frog. This is not always true as there are two types of carotenoids, polar and non-polar. Most carotenoid uptake is passive along with digested fats and polar carotenoids are very poorly absorbed because of this manner of uptake (they don't form micells well) which is why paprika (in which the red carotenoids are polar) usually results in a poor increase in color (although it does supply beta carotene).

So right off the bat by looking at husbandry impacts we can see that breeding the largest and most colorful is an artificial selection mechanism as it may not reflect the "best stock". 

There are a lot of traits that cannot be readily assessed on a visual or aesthetic appeal that are crucial to the captive population. One of the main ones is the genetic control of the histocompatability complexes. These control disease and parasite resistence and one of the consequences of artificial selection is a loss of these genes resulting in a population that is very susceptiable to one or more pathogens. 

I need to take a break but this is where the discussion needs to start. Yep I was right I can't avoid being verbose...


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## skylsdale

chuckpowell said:


> When I think big, colorful frog I think of what I see come in from the wild, what has been selected in the wild as "the best."


But what comes in from the wild aren't necessarily the most fit as Nature has determined...but "the best" as based on the subjectivity of a collector. What will sell well, etc. It could be that we primarily end up with a limited phenotype representation from any given population because the collectors noticed frogs with a certain general pattern or coloration more than others from within the population. 

Granted, things come in skewed...but for me, the point is to try and maintain the wild integrity of the frogs, which is what interests me about them. I think if we stray from that, then the likely inevitable outcome is that this hobby will go the path of dog breeding (or snake/gecko breeding) and folks will be breeding various designer and "novel" morphs, slapping their names on them and getting the quick fame/fortune as is currently happening in the python hobby. In that case, "best" usually means "no one else has it but me."

Also, I realize my desire for how/why I want to maintain wild-type frogs is my personal desire and might not reflect others in the hobby. That's why I think the ASN and the ability for hobbyists to work within actively managed taxon groups will help provide a safety bubble for those who share those desires. The frogs that form the founding population of a Taxon Management Group will be tracked and bred for maximum diversity and wild-type genetic sharing. This will ensure that wild-type frogs are preserved (and available) within the hobby, even if designer and heavy selective breeding becomes the norm. What happened in the corn snake hobby was that so much of the latter was going on, things actually reached a point where a wild-type corn snake was actually next to impossible to find...which resulted in further collection from the wild to meet the 'new' demand of wild-type snakes. I think that's a bit of history we can/should learn from and, as a hobby, try to prevent...or at least mitigate as much as we are able to.


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## Ed

Some further comments.. (I have to keep it short as I have to get organized for the 4-H herp club tonight). 

As we saw with my earlier post, there are a host of enviromental and nutritional husbandry factors that have a good probability to be affecting the frogs, which are mistaken by many people as genetic in origin instead of being artifacts of captive management. Now onto some of the genetics.. 


One of the most important things that can be significantly impacted through the subjective choice of mates is the immune system of the frogs. This is the major histocompatability complex which is under genetic control. The greater the loss of genetic variation of the histocompatability complex, the more chances the frogs are going to be susceptiable to diseases and/or pathogens and/or parasites, as the immune system becomes more compromised. The reason I mentioned random mate selection instead of that based on a standard, is because if the frogs are denied the ability to evaluate fitness, then you have to remove any subjective bias on the part of the keeper as that will still cause artificial selection. If the populations were being managed by a system like that of Zoos, the animals and thier offspring would be entered into a database which would allow the TMP manager to watch for frogs that were underrepresented in the gene pool and suggest options for increase that representation. It would also give the option for suggestion for frogs that are overrepresented that breeding of those frogs be reduced. However the hobby doesn't utilize TMPs in that manner, so we can't follow that path (the closest we have the ASN, which just tracks registered populations, which would hopefully help prevent population cycles). As a result we need to remove selection bias on the part of the keeper in the choice of pairing up the frogs which is why I mentioned random pairings. A population that was well registered through a program like ASN would allow keepers to check with the TMP manager to locate a maximally unrelated group of the same frog (population and/or import) which could be randomly selected as an option but since most of the frogs in the hobby are unregistered in either ASN or FrogTracks that option is closed to most of the hobby.. the final option to attempt to sustain the population is to randomly select frogs from the same import/captive population. This has a better chance of sustaining genetic diversity but the captive populations are still going to be at risk in the future as this isn't using the best tools available to the hobby (kind of like attempting to cut down a tree with a steak knife instead of a chainsaw). 

A number of people in several different threads have mentioned "allowing nature to take its course" or "only the strong survive". If there is any interest in the frogs being available in captivity for the long haul, then this should be avoided as assidously as hybridization or crossing of morphs. The reason is that this is a form of direct selection for frogs that are adapated to the captive conditions (breeding conditions 24/7) which is a loss of the important genetic diversity. There is nothing natural about it because all of the conditions are artificial artifacts of husbandry including diet of parents, incubation methods, tadpole rearing, and froglet rearing. This is as natural as the caesarean births needed to perpetuate old English Bulldogs or laying chickens that have had the drive to incubate eggs bred out of them. The thing most people miss is that not every frog needs to breed but the keeper shouldn't be chosing the mates based on aesthetics. 

Group housing was mentioned in a different post above, which allows for mate choice but there are pitfalls with this as well. An example of a potential problem with this mechanism is that the frogs who are best adapted to captivity are going to be at an advantage.. and ideally you would have to be able to figure out which frogs are the most unrelated within that captive population/morph. The mechanisms to make those choices, while available are under utilized.


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## earthfrog

> A number of people in several different threads have mentioned "allowing nature to take its course" or "only the strong survive". If there is any interest in the frogs being available in captivity for the long haul, then this should be avoided as assidously as hybridization or crossing of morphs. The reason is that this is a form of direct selection for frogs that are adapated to the captive conditions (breeding conditions 24/7) which is a loss of the important genetic diversity. There is nothing natural about it because all of the conditions are artificial artifacts of husbandry including diet of parents, incubation methods, tadpole rearing, and froglet rearing. This is as natural as the caesarean births needed to perpetuate old English Bulldogs or laying chickens that have had the drive to incubate eggs bred out of them. The thing most people miss is that not every frog needs to breed but the keeper shouldn't be chosing the mates based on aesthetics.
> 
> Group housing was mentioned in a different post above, which allows for mate choice but there are pitfalls with this as well. An example of a potential problem with this mechanism is that the frogs who are best adapted to captivity are going to be at an advantage.. and ideally you would have to be able to figure out which frogs are the most unrelated within that captive population/morph. The mechanisms to make those choices, while available are under utilized.


What he said. This part is pretty vital to understand... bigger ain't always better...and breeding for the unusual is asking for trouble later on down the line for yourself and everyone else...


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## SmackoftheGods

Ed said:


> Group housing was mentioned in a different post above, which allows for mate choice but there are pitfalls with this as well. An example of a potential problem with this mechanism is that the frogs who are best adapted to captivity are going to be at an advantage.. and ideally you would have to be able to figure out which frogs are the most unrelated within that captive population/morph. The mechanisms to make those choices, while available are under utilized.


That's why I mentioned that it wasn't fool-proof... still I think it beats putting two breeders in the same tank and having _only_ them breeding for their lives....

I'm currently housing a 2.2 group of variabilis. There is a dominant male and a dominant female who do most of the breeding. So it's true, it is not without its pitfalls (and I'm not sure whether dominance in this group is due to the fact that some are better adapted to captivity or some are just "better" frogs). However, the submissive male and submissive female do manage to do their share of breeding. They're slightly smaller than their counterparts, but they're quicker and sneakier about what they do. There's a higher rate of egg eating of these eggs, but some of them do manage to make it....

Again, not without its pitfalls, but a better overall situation than having a 1.1 that may or may not be genetically different enough to help support a captive population, yes?


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## MonarchzMan

SmackoftheGods said:


> That's why I mentioned that it wasn't fool-proof... still I think it beats putting two breeders in the same tank and having _only_ them breeding for their lives....
> 
> I'm currently housing a 2.2 group of variabilis. There is a dominant male and a dominant female who do most of the breeding. So it's true, it is not without its pitfalls (and I'm not sure whether dominance in this group is due to the fact that some are better adapted to captivity or some are just "better" frogs). However, the submissive male and submissive female do manage to do their share of breeding. They're slightly smaller than their counterparts, but they're quicker and sneakier about what they do. There's a higher rate of egg eating of these eggs, but some of them do manage to make it....
> 
> Again, not without its pitfalls, but a better overall situation than having a 1.1 that may or may not be genetically different enough to help support a captive population, yes?


Why would you have only that pair breeding their whole lives?

Take your variabilis, for example. If you had two tanks, you could periodically pair up frogs as Male 1 with Female 1 and Male 2 with Female 2, then after a year, switch it to Male 1 with Female 2 and Male 2 with Female 1. Then you would have maximum genetic variability being produced within your group rather than have one pair doing most of the breeding. And you wouldn't have the one pair constantly breeding with one another, but breeding with all possible mates (and you'd avoid the egg eating).


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## chuckpowell

Why wouldn't what comes in the wild be the most fit - I would think the weak would have been killed... you know only the strong survive. And I think you don't understanding collecting by native people - they'll collect anything and everything they can get money for. They don't care about the pattern. They want as many frogs in as short a time period as they can get. If one of us went to collect frogs things would likely be different, but how often does that happen. 

I believe we're already producing "designer" morphs. I mean please, azureus - sky blue, dark blue, large spot, small spot.... We pick the animals we like and they produce, mostly, similar looking animals. We haven't taken this nearly as far as ball pythons, leopard geckos and lets not forget corn snakes, but we're doing it none the less weather we want to or not. You state in your last paragraph your trying to maintain "wild type frogs." These could be considered a designer morph, a wild type morph. 

But all this is missing my questions. What should we be looking for, or looking to produce in frogs suitable to our cages long term? Just saying genetic diversity doesn't help - you can see it and you can't really breed for it - it just happens with what your given. So does anyone have an idea of what we should look for to keep the frogs similar to their wc ancestors for 20, or 30, or 40 years. I've been in the hobby over 25 years, continuously, and the look of animals has changed over that time. What do we do to slow this "evolution" so our frogs look more like wc. We're not doing it now. 

Best,

Chuck



skylsdale said:


> But what comes in from the wild aren't necessarily the most fit as Nature has determined...but "the best" as based on the subjectivity of a collector. What will sell well, etc. It could be that we primarily end up with a limited phenotype representation from any given population because the collectors noticed frogs with a certain general pattern or coloration more than others from within the population.
> 
> Granted, things come in skewed...but for me, the point is to try and maintain the wild integrity of the frogs, which is what interests me about them. I think if we stray from that, then the likely inevitable outcome is that this hobby will go the path of dog breeding (or snake/gecko breeding) and folks will be breeding various designer and "novel" morphs, slapping their names on them and getting the quick fame/fortune as is currently happening in the python hobby. In that case, "best" usually means "no one else has it but me."
> 
> Also, I realize my desire for how/why I want to maintain wild-type frogs is my personal desire and might not reflect others in the hobby. That's why I think the ASN and the ability for hobbyists to work within actively managed taxon groups will help provide a safety bubble for those who share those desires. The frogs that form the founding population of a Taxon Management Group will be tracked and bred for maximum diversity and wild-type genetic sharing. This will ensure that wild-type frogs are preserved (and available) within the hobby, even if designer and heavy selective breeding becomes the norm. What happened in the corn snake hobby was that so much of the latter was going on, things actually reached a point where a wild-type corn snake was actually next to impossible to find...which resulted in further collection from the wild to meet the 'new' demand of wild-type snakes. I think that's a bit of history we can/should learn from and, as a hobby, try to prevent...or at least mitigate as much as we are able to.


----------



## Ed

chuckpowell said:


> Why wouldn't what comes in the wild be the most fit - I would think the weak would have been killed... you know only the strong survive. And I think you don't understanding collecting by native people - they'll collect anything and everything they can get money for. They don't care about the pattern. They want as many frogs in as short a time period as they can get. If one of us went to collect frogs things would likely be different, but how often does that happen.


Hi Chuck, 

You are mistaking fitness of an individual with the fitness of a population. They are not necessarily the same thing. It is possible for an individual animal to exceedingly well adapted to its conditions yet when it passes it's genes along the fitness is lost due to changes in allele frequency, resulting in a population that is on the route to extinction. You are somewhat correct in assuming that the frogs who have genes that make them less able to adapt to captive conditions are going to die but you can't make the assumption that this always occurs before the frogs arrive or shortly after they arrive as other factors come into play such as length of time held both in and out of country of origin as even frogs with the optimal genes will die if held improperly long enough. 

Any time you allow bias to select the breeders you are working towards a loss of alleles including critically important alleles such as those of the histocompatability complex.


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## SmackoftheGods

MonarchzMan said:


> Why would you have only that pair breeding their whole lives?
> 
> Take your variabilis, for example. If you had two tanks, you could periodically pair up frogs as Male 1 with Female 1 and Male 2 with Female 2, then after a year, switch it to Male 1 with Female 2 and Male 2 with Female 1. Then you would have maximum genetic variability being produced within your group rather than have one pair doing most of the breeding. And you wouldn't have the one pair constantly breeding with one another, but breeding with all possible mates (and you'd avoid the egg eating).


This is a far more ideal solution, you're right. And had I the room this is _absolutely_ the route I would take. Maybe someday I'll actually be _able_ to do this. However, for now I have limited space (and pretty limited time). I do frogs on a pretty small scale (bigger than many, smaller than any of the true breeding projects that I know some of the members on here have going). At the moment I'm trying to do what's best within my ability....



chuckpowell said:


> Why wouldn't what comes in the wild be the most fit - I would think the weak would have been killed... you know only the strong survive.


Has anyone considered the idea that perhaps by collecting we are splitting frog populations into two groups (in terms of survival of the fittest)? Group A: those that get caught, Group B: those that don't get caught. Just as a hypothetical, could collecting wild frogs be a form of selection in that those that are collected have a greater propensity (for whatever reason, be it more boldness, less speed, larger frogs that are easier to be seen, etc) to be collected, and those that remain in the wild have features that give them less of a probability of being collected? Were this the case it seems that it might account fo why the wild caught frogs that come into the hobby would not represent the population as a whole.... Then again this is a _total_ shot in the dark....


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## PeanutbuttER

SmackoftheGods said:


> Has anyone considered the idea that perhaps by collecting we are splitting frog populations into two groups (in terms of survival of the fittest)? Group A: those that get caught, Group B: those that don't get caught. Just as a hypothetical, could collecting wild frogs be a form of selection in that those that are collected have a greater propensity (for whatever reason, be it more boldness, less speed, larger frogs that are easier to be seen, etc) to be collected, and those that remain in the wild have features that give them less of a probability of being collected? Were this the case it seems that it might account fo why the wild caught frogs that come into the hobby would not represent the population as a whole.... Then again this is a _total_ shot in the dark....


I've wondered about this same thing. Native collectors are just going at it grabbing whatever they can get most easily (I assume). So it makes sense that those individual frogs that for instance are more "bold" in a wild setting would have an easier time getting spotted, caught, and possibly founding a line. Nothing to prove it (nor would I honestly care to), but it seems reasonable to me.


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## Ed

SmackoftheGods said:


> Has anyone considered the idea that perhaps by collecting we are splitting frog populations into two groups (in terms of survival of the fittest)? Group A: those that get caught, Group B: those that don't get caught. Just as a hypothetical, could collecting wild frogs be a form of selection in that those that are collected have a greater propensity (for whatever reason, be it more boldness, less speed, larger frogs that are easier to be seen, etc) to be collected, and those that remain in the wild have features that give them less of a probability of being collected? Were this the case it seems that it might account fo why the wild caught frogs that come into the hobby would not represent the population as a whole.... Then again this is a _total_ shot in the dark....


It is possible depending on how the populations are distributed. If the locals are hitting up the areas of population densities (as there is a cut off point for when it is no longer economical worthwhile) then you are going to have the outlying frogs moving back into those optimal zones once collecting ceases. 
If they are collecting all of the frogs from a population regardless of the densities then you could in theory see a change in pattern and/or behaviors. 

Ed


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## skylsdale

Just some reading related to the topic: Interspecific and intraspecific views of color signals in the strawberry poison frog Dendrobates pumilio


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