# Line Breeding Opinions



## Frogtofall (Feb 16, 2006)

Alright, I've been bleeding from my ears for the last few weeks trying to figure out where I stand on the whole line breeding subject, particularly with D. imitator. I did a search in the Advanced section, but did not find a subject on just line breeding that satisfied me enough. So here it goes...

I've spoken to a few different hobbysits and they each have had their own opinion on the subject. Some say they want to preserve a line b/c of the way the lines "look" and some say b/c they might come from different locales. Others think that its a bad idea b/c of the genetic factor (inbreeding being a bad thing for the gene pool).

With D. imitator, I know that there are a few different lines like, Kelly, Sens, Neighbors etc. There are also different MORPHS of these frogs like, Standard, Tarapoto and Yurimaguensis. Now I would NEVER consider breeding different morphs, but lately I've been thinking it would benefit the gene pool by cross breeding different lines.

This brings me to another aspect. It seems some are line breeding just to preserve the look of the frog which sorta seems kinda selfish. You'd risk deformities just so that all your frogs could look the same? Its like we're acting like Frog Hitlers or somthing. Heh.

Also, why would some breeders out there make it a point to offer unrelated lines of other species of frogs like D. azureus to breed? Like on Saurian.net, he offeres unrelated azureus lines to breed with. Then you go to another species from someone else and all they sell are Sens line imitators or Kelly line imitators. Isn't line breeding seriously detrimental to the gene pool?

How many lines might one breeder have? That could also come into play. I think I remember hearing that P. Neighbors had a couple different lines of intermedius. Would you cross breed the two different lines so long as they are the same morph?

Look at dogs for instance. There are many lines of working line German Shephards in the country. Many are champion lines. Do you think these breeders breed all their dogs in the kennel with their siblings or parents? Nope, they bring in other working lines of the same breed to bring good blood into the kennel. Why should it be any different with frogs?

As I type this, I think I've come to realize that from a purley scientific aspect, its probably not the best idea to line breed. I honestly could care less how my Kelly line imis look compared to someone else's Sens line. You got a male from Sens' line? I got a female from Kelly's line, lets breed them to increase the diversity and better the life of these frogs.

Where do you stand?


----------



## bluedart (Sep 5, 2005)

Line breeding is, has, and probably will be for quite some time a controversial subject. With so many different species and morphs of darts, coming in at so many different points of the hobby, it's difficult to decide exactly how to proceed with this "line breeding" concept. But, I believe line breeding is inappropriate under most circumstances due to the unreliability of information, the possible individual gene pool dilution, and because of the possible hobbyist repurcussions that may accompany it.

First off, there are vast differences between line breeding imitator and interline breeding with azureus. An azureus is an azureus no matter where it comes from, as they don't seem to have too much differentiation depending on where they come from. They do to some degree, but the hobby has already done lots of inbreeding. The "sky blue" azureus is, I believe, simply a genetic mutation that has been line bred itself, which I personally don't agree with. But, I think a different analogy may be more appropriate to paint this picture. Take D. tinctorius for example. The color pattern variations amongst the tincs are unbelievable, yet they're all more or less the "same frog"--Dendrobates tinctorius. We keep these seperate because of the fact that they look SO incredibly different, and we know for a fact that these are specific morphs, from specific areas (but we just don't always know exactly where). So, do you believe that just because they are the same species that it's ok to outcross them? According to most hobbiest morals, it's not. Same thing with standard D. imitator. You've got the blue legs, the grey legs... green legs... etc. These are clearly differences, because they presumably came from different locales. A difference should be defined as a color, pattern, or body shape/posture differentiation from another frog of the same morph. Now, it is obvious that the mild coloration differences between imitator lines are different from the coloration differences between tinctorius morphs, but the concept is the same. These frogs differentiated because they were from different locales, just as the tincs did. So, to outcross imitator wouldn't be much different from outcrossing a Cobalt to a Patricia.

Now, if we had full collection information for the imitator, and found that grey and blue leg imitator were from the same area, it *might* be ok. But, then we begin to ask ourselves why wouldn't there be bluish grey imitator for the most part, with only rare examples of the vivid blue and the hazy grey? Well, because they weren't from the same local. These lines are individual gene pools, and outcrossing them would be unethical. But, what if we did? What if we did begin to line breed these imitator, then what would happen? I believe the most notorious line breeding operation in the history of the herp hobby is the leopard gecko. Those wild caught animals have been line bred to the extreme, to where it is nearly impossible, without prior knowledge, to compare a SHTCTB Leopard gecko to a wild one and say these are the exact same species. These animals were bred to look like this through lots of inbreeding, but that's not what our hobby is about. Our hobby is about preserving these animals as they look in the wild, not to hybridize, or breed for certain characteristics.

Now, sure, it might be ok to intermingle these lines a bit. It might would be ok if we were down, at some point, to just a few pairs of each line, and we did it to overall preserve the species in captivity. But, fortunately we're not at that point, and hopefully we never will be. All of the animals in captivity, and the wild, are somewhat related, and in the wild they wouldn't hesitate to breed with a close relative if it was convenient at the time. So, overall, line breeding is not a necessity for these animals at the moment. Europe has been interbreeding siblings and cousins for decades at a time without repurcussions. Sure, some deformitys may show up, but if we continue to attempt to breed cousins rather than siblings, then we will hopefully be able to maintain strong lines for years to come.


----------



## Rain_Frog (Apr 27, 2004)

This is a major problem with this hobby.

I do not believe we will come up with a solution in the near future though.

I personally think crossing bloodlines (not morphs) is very important to preserve their health. However, many frogs originate from one line of frogs (like tricolor) and unless they are imported again (and still may not be different genetically if its the same population) chances are you'll still be line breeding.

I think one thing that we should be doing is culling the weaker tadpoles/froglets as even in nature most will not survive. Trying to ensure all the tadpoles of a clutch survive is somewhat unnatural and you could have animals that have recessive traits that are allowed to breed...further damaging the heredity health of the animals.


----------



## bluedart (Sep 5, 2005)

Rain_Frog said:


> This is a major problem with this hobby.
> 
> I do not believe we will come up with a solution in the near future though.
> 
> ...


People tend to take a special liking to the sickly froglets, and really want them to make it. Honestly, it's probably better to let them die, as they'll weaken the gene pool if allowed to breed. I think that communal raising, while not the best for overall production numbers, is probably best for the tads and line.


----------



## Frogtofall (Feb 16, 2006)

I've never seen D. imitator advertised as "Blue leg" or "Grey leg" or even "Green leg" before. I know vents and lamasi are, but not imitator. I'm not saying they don't exist that way, I've just not seen them. But even still, these are all standard morph imitator are they not then? Just variations in leg color.

The tinc point doesn't apply here as the tincs are all different morphs. But even in the same morphs like the cobalt, you get huge differences in coloration. Some come out pastel and some come out with high orange/yellow, yet people cross them.

My imis are Todd Kelly line. I'd like to know how many lines of imitator he has and how different they all look. It might help me a bit.


----------



## bluedart (Sep 5, 2005)

Frogtofall said:


> I've never seen D. imitator advertised as "Blue leg" or "Grey leg" or even "Green leg" before. I know vents and lamasi are, but not imitator. I'm not saying they don't exist that way, I've just not seen them. But even still, these are all standard morph imitator are they not then? Just variations in leg color.
> 
> The tinc point doesn't apply here as the tincs are all different morphs. But even in the same morphs like the cobalt, you get huge differences in coloration. Some come out pastel and some come out with high orange/yellow, yet people cross them.
> 
> My imis are Todd Kelly line. I'd like to know how many lines of imitator he has and how different they all look. It might help me a bit.


Yes, but the blue leg imi, which are oft found within the Todd Kelley line, will also vary in the intensity of color, but we still breed them. Do a search in the gallery of imitator, and then compare all the pics you see. There will be lots of different imitator. The tinc analogy actually works very well, as I've discussed it several times with some other board members since I posted it.


----------



## Frogtofall (Feb 16, 2006)

I know the different lines look different, but to my knowledge, they are all still standard morph imitator. The differences aren't great enough to subject them to morphological nomenclature (Is that a term? LOL). I just said I hadn't seen them advertised that way.

Your tinc analogy doesn't work b/c I stated that I wasn't talking about different morphs of imitator and your tinc point was using different morphs of tincs and crossing them. I stated in the first post that I would NOT want to cross morphs. Make sense?



bluedart said:


> Take D. tinctorius for example. The color pattern variations amongst the tincs are unbelievable, yet they're all more or less the "same frog"--Dendrobates tinctorius. We keep these seperate because of the fact that they look SO incredibly different, and *we know for a fact that these are specific morphs*, from specific areas


----------



## trinacliff (Aug 9, 2004)

Another name for this thread could be CAN O' WORMS...hehehe. 

Sorry I'm not gonna get in the middle of this, since I just want to sit back and watch. heh heh :twisted: 

Kristen


----------



## bluedart (Sep 5, 2005)

Frogtofall said:


> I know the different lines look different, but to my knowledge, they are all still standard morph imitator. The differences aren't great enough to subject them to morphological nomenclature (Is that a term? LOL). I just said I hadn't seen them advertised that way.
> 
> Your tinc analogy doesn't work b/c I stated that I wasn't talking about different morphs of imitator and your tinc point was using different morphs of tincs and crossing them. I stated in the first post that I would NOT want to cross morphs. Make sense?
> 
> ...


What is your definition of a morph, then?


----------



## Dancing frogs (Feb 20, 2004)

I don't know much of the foundation of those (imitator) lines...but if they came in at different times, and they breed true for the color/pattern, they should be considered separate, and not interbred with different lines.

If in doubt contact the breeder...


----------



## Frogtofall (Feb 16, 2006)

trinacliff said:


> Another name for this thread could be CAN O' WORMS...hehehe.
> 
> Sorry I'm not gonna get in the middle of this, since I just want to sit back and watch. heh heh :twisted:
> 
> Kristen


Aww c'mon!! This doesn't need to get hairy, I just like to read people's opinions on this stuff. I've spoken to you about it, so you know!!


----------



## Frogtofall (Feb 16, 2006)

bluedart said:


> What is your definition of a morph, then?


My definition of a morph...

The difference between to different animals of the same species which could be based on color/pattern and/or locality. We'll use tinctorius as they are the most common for this type of subject.

Look at the yellow back vs the cobalt. Huge difference, those are different morphs. But then look at some cobalts...

I have cobalts from the same parents that are COMPLETELY different looking in color and pattern. One has a solid yellow/orange head that flows into two separate stripes on its back. The other has a light yellow head thats flows into two blue pastel stripes with a tiny bit of netting. Yet, these aren't different morphs, just color/pattern differences among the same morphs. For the unknowing, someone could assume they were different morphs based on pattern and color differences though.

So to me, since the different lines of D. imitator haven't been given different morph names, I assumed (thats probably the problem) that they are not different morphs, but just different bloodlines that contain different color variations but are not deemed different morphs. This then leads me to feel that crossing them is not the same as crossing a Cobalt with a Yellowback tinctorius or a Tarapoto and a Yurimaguensis imitator.


----------



## bluedart (Sep 5, 2005)

That's not a bad crack at defining a morph. A morph is normally based on color and locale compared to the color and locale of others of the same species. So, sure, lets take cobalts. I'll give it to you, they all have different shade and patterns. And, yes, to the untrained eye they may be confused. But, as hobbyists, it's kind of our job not to be confused, and we should have trained eyes. And, what about all of the different green and black auratus morphs? Oftentimes, they look extraordinarily similar. Really, the question about these imitator are what are the lines kept. These lines are kept because these imitator were collected from different locales. They look different, and we try to keep these lines pure. You can kind of think of these lines as mini morphs, as in they're not exactly different "morphs", persay, but rather they have enough genetic variation to be kept separate. The big picture is locale, much more so than color, though it does play a picture. Because of these locale differences, we don't interbreed lines. Interbreeding the lines together would be a great disfavor to the hobby, and to those who have worked hard to keep the lines pure. Then, what to do with the babies? What do you call them, or sell them as? It just basically removes one piece to the 1000 jugsaw puzzle, burns it, and flushes the ashes.


----------



## Frogtofall (Feb 16, 2006)

Well then there are a lot of babies that need to be destroyed then by that definition.

It was recommended to me by a certain breeder (no names) that I obtain a different bloodline for my intermedius than the bloodline that I have. I have to agree with him/her.

So I have a green tree frog from Florida and you have one from Missouri. Yours has a slight reddish on the white line. You wouldn't lend me your frog to breed with mine?

I honestly didn't know that the different lines meant that the frogs were necessarily from different locales. I just assumed (again here I go with assumption) that they were given line names b/c that particular breeder brought them in and gave them their line name.

So by that, maybe these all SHOULD be given different morph names.


----------



## defaced (May 23, 2005)

> A morph is normally based on color and locale compared to the color and locale of others of the same species.


A) Does Imitator have a broad range of locals? Are the Imitators in the hobby from one local or several local?

B) IMO, color is second to local. As said before, look at Azureus. Same frog, but there is variation in color and pattern just as with other frogs. So why the lack of definitions for Azureus? With Tincs, there is information supporting different locals and that is used as the explaination for different color, and that is why we keep them seperate. Local before color. 

Without local information, the Imitator situation looks just like if someone bred Azureus for a particualr pattern and color and said it was a Bob's Line Azureus.


----------



## Ed (Sep 19, 2004)

Here is where it gets problomatic, those "lines" represent different importations of the frogs potentially from different localities and while morphologcally identical/similar may represent distinct genetic groupings. Back in the days those frogs came into the country, the exporters/importers did not track any locality data as it was not important to the market so the onyl way we have to track potentially distinct genetic groupings are by the lines that were established at the time of the importations. 
I would suggest not mixing those lines until the analysis has been done to show that they are not gentically distinct. If you are not willing to intermix visible morphs why would you be willing to intermix nonvisible morphs? The only difference is that you can distinguish one due to external characteristics? 

Ed


----------



## bluedart (Sep 5, 2005)

defaced said:


> > A morph is normally based on color and locale compared to the color and locale of others of the same species.
> 
> 
> A) Does Imitator have a broad range of locals? Are the Imitators in the hobby from one local or several local?
> ...


A) Depending on your opinion of a "broad" range, then, yes, imitator can be considered to have a broad range. Because we lack the collection data on most of our imports, we do not know for certain whether the different lines are from different locales, but it is presumably so. These lines could be genetically different to a degree from other lines (due to different locales), therefore, until we have genetic research done on different lines to prove otherwise, we don't mix the lines. As Ed said, is the only thing that determines a different morph external evidence?

B) snip "The big picture is locale, much more so than color, though it [color] does play a picture. " - bluedart.

My belief is that Azureus were line bred by a different definition, in that they were line bred to look like the sky blues, or to have the smaller spots. It is possible, as well, that they simply came looking like that from importation, but information was not properly kept, and we've lost what we could've used to define it as a "line", persay. I think much of what will be said about azureus will be speculation, but I would love to hear from somebody who knows a good deal about the introduction of azureus to the hobby. If I'm correct, they were introduced illegally in the beginning.


----------



## Frogtofall (Feb 16, 2006)

Ed,

Is there any testing being done to determine if the D. imitator we have now are genetically distinct?

I'm having a somewhat difficult time understanding why its so important to keep the lines separate if they were genetically distinct, but didn't look any different. At least majorly. The differences in the lines now are about as variant as the different Cobalt tinc variants. Wouldn't it be better for the species to have genes from different areas so long as its not a completely different morph? Or is the genetic difference enough to say its a different morph and shouldn't be crossed? And would we not want to cross them b/c in nature it wouldn't happen per se?


----------



## defaced (May 23, 2005)

Lack of information with Azureus means people breed indescriminately.

Lack of information with Imitator means people create lines and keep them seperated. 

Correct?


----------



## Ed (Sep 19, 2004)

snip "I'm having a somewhat difficult time understanding why its so important to keep the lines separate if they were genetically distinct, but didn't look any different."endsnip

An example, what if this is a species or subspecies complex that is not detemined until after the animals have been interbred. It is not uncommon for there to be species complexes of visually identical or similar species.. For example, Epidobates boulengeri complex, Bufo typhonius complex to name two anuran based ones right off the bat. (There are a number of caudates that cannot be detemined through visual appearences if the collection locality is not known unless DNA work is done on the animal. )
This cannot be determined through visual inspection. A genetic analysis is required to determine the extent of differentiation. 


snip "At least majorly. The differences in the lines now are about as variant as the different Cobalt tinc variants. Wouldn't it be better for the species to have genes from different areas so long as its not a completely different morph?" endsnip 

Did you misstate this? If the variation in the "lines" is as significant as the variaton in the tinct morphs, doesn't this in and of itself speak to different locality origins? If we as a group are not hybridizing tinct morphs why would we hybridize these? 

snip "Or is the genetic difference enough to say its a different morph and shouldn't be crossed? And would we not want to cross them b/c in nature it wouldn't happen per se?" endsnip 

Once you start down the road to hybridization, then you lose the unique characteristics that make that line unique. It is more than the idea than that cross would not occur in nature but more as a goal to preserve the frogs in captivity as close to the form it evolved into as possible. Not to preserve them for release or repatriation as this is unlikely (but the miniscule chance would be reduced to zero if they are hybridized, look up the story of the dusky seaside sparrow for how this would work out) but to preserve them for future generations. 
Not only that, listing it as a hybrid is not a guarantee that it or its offspring will continue to be labeled as such. Look how often someone on here asks to get a frog identified as to a morph based solely on its visual characteristics. What if the frog is a hybrid and is simply expressing sufficient characteristics to get it lumped into that group?? 

I understand the idea that the outcrossing could introduce new vigor into the lines but this also means that gene combinations that make those lines unique would also be lost. One of the ways to deal with this loss is to find someone who has a long established line of the same line you are breeding and cross the offspring with thiers. So sens x sens etc. Any loss of genes in thier line would likely be different than any bottlenecking seen in your line and the deleterious genes get diluted again. For this to work to the best ability people need to register thier frogs to determine thier interrelatedness and how represented thier genes are within the group. While the sens line may be well represented, one breeder may have introduced more of his line of sens frogs into the trade than another person causing these gene combinations to become more represented and the effects amplified. 

Some thought

Ed


----------



## Ed (Sep 19, 2004)

Azureus are different. Check with Chuck Powell for the scoop on azureus. 

With the different morphs of azureus, these popped up within the population and people selected for these traits. Actually people bred more selectively to lock these traits down. 

Ed


----------



## Frogtofall (Feb 16, 2006)

Ed,

Thanks for your input. Its always relieving to read what you have to say. You answer questions perfectly.

On the tinc thing... I didn't misstate what I was saying, but I may have been too vague. I was referring to the variance we see in the Cobalt morph of D. tincotrius. Basically, I have 2 Cobalts of the same parents that look nothing, and I mean NOTHING alike as far color and pattern.

Either way, you cleared a lot of the cloudiness I had in my head about the subject, and I now see it in a different light. How I see it now is that keeping the lines separate will ensure that we keep the frogs as close to their original or natural state as possible.

Do the guys (Sens, Kelly etc) that brought the frogs in have the collection data on their lines of frogs? Or should I ask, should they have it but probably don't?


----------



## RGB (Jan 15, 2006)

I’d like to offer a few ideas on this subject. First off, I have to admit that I don’t have any experience with breeding frogs so some of my ideas may be misinformed. If I state anything that seems absurd please let me know as I’m here to learn as much as I can. I must admit this topic is a little confusing due to the fact that I don’t know the specific locations each morph comes from. So to keep things simple I’ll use hypothetical frogs and locales.

Say you have Frog 1 from Locale 1 and Frog 2 from Locale 2, both belonging to the same species. Then assume that we have both spotted and striped frogs from each location. In nature we can assume that any frog from locale 1 can breed with any other frog from locale 1 regardless of pattern. If we only allow spotted frogs from locale 1 to breed and don’t include striped frogs from locale 1 aren’t we guilty of breeding for a specific trait? 

Then say we have two spotted frogs, one from locale 1 and one from locale 2. These frogs would never breed in nature so why should we intermix them simply based on outward appearance. I guess the point I’m trying to make is that to me, location seems to be the only way to determine what frogs should be bred.

Back to reality:
I think I read somewhere that azureus come from a very small area in Surinam. If I remember correctly, it was an area the size of a football field. If this info is true, there is only one population in the wild and any member of that population should be able to breed with any other member. If this is the case, we should have no distinctions in the azureus we produce in the hobby. Fine spots and large spots or sky blue and dark blue should not be kept apart simply because we like the looks of one over the other. They should be kept as one morph and any variation in color or pattern should be left to nature to decide, or genes if you prefer.

Not trying to say anybody is being irresponsible or over-careful but I think we should try to follow natural selection whenever possible even though our little glass boxes make that pretty difficult.


----------



## Ed (Sep 19, 2004)

snip "On the tinc thing... I didn't misstate what I was saying, but I may have been too vague. I was referring to the variance we see in the Cobalt morph of D. tincotrius. Basically, I have 2 Cobalts of the same parents that look nothing, and I mean NOTHING alike as far color and pattern. "endsnip 

This may simply be an artifact of a larger phenotypic variation within the morph and is another reason why people shouldn't necessarily be going on simply how the frog looks. (It could also be influenced through dietary additives). 


snip "Do the guys (Sens, Kelly etc) that brought the frogs in have the collection data on their lines of frogs? Or should I ask, should they have it but probably don't?" endsnip 

These lines were started when there wasn't any collection information but came through in different importations so they were maintained seperately. 
Keep in mind that some of what we call locality data is not real locality data but points where the animals were shipped to a spot to be exported or the exportation point..... 


snip "Say you have Frog 1 from Locale 1 and Frog 2 from Locale 2, both belonging to the same species. Then assume that we have both spotted and striped frogs from each location. In nature we can assume that any frog from locale 1 can breed with any other frog from locale 1 regardless of pattern. If we only allow spotted frogs from locale 1 to breed and don’t include striped frogs from locale 1 aren’t we guilty of breeding for a specific trait? " endsnip 

In essence yes and people are currently doing just this with some of the pumilio imports that in the wild are polymorphic. Keep in mind though you need to be careful how you define locality; for example if some says Sipaliwini, there are several tinct morphs associated with this region as well as D. azureus. 

snip "Then say we have two spotted frogs, one from locale 1 and one from locale 2. These frogs would never breed in nature so why should we intermix them simply based on outward appearance. I guess the point I’m trying to make is that to me, location seems to be the only way to determine what frogs should be bred" 

Yes but in the case where the locality is unknown then the closest we can come is to frogs that came into the country in the same importation. 

snip "I think I read somewhere that azureus come from a very small area in Surinam. If I remember correctly, it was an area the size of a football field. If this info is true, there is only one population in the wild and any member of that population should be able to breed with any other member" 

They come from primary forest remnants on one slope in the Sipaliwini region. The remnants can be as small as a foot ball field but can also be much larger. 

Ed


----------



## RGB (Jan 15, 2006)

Ed said:


> snip "Say you have Frog 1 from Locale 1 and Frog 2 from Locale 2, both belonging to the same species. Then assume that we have both spotted and striped frogs from each location. In nature we can assume that any frog from locale 1 can breed with any other frog from locale 1 regardless of pattern. If we only allow spotted frogs from locale 1 to breed and don’t include striped frogs from locale 1 aren’t we guilty of breeding for a specific trait? " endsnip
> 
> In essence yes and people are currently doing just this with some of the pumilio imports that in the wild are polymorphic. Keep in mind though you need to be careful how you define locality; for example if some says Sipaliwini, there are several tinct morphs associated with this region as well as D. azureus.


Okay, that makes sense. I was just trying to look at the simplest possible situation. Is there anything that prevents these morphs from interbreeding in the wild? 



Ed said:


> snip "Then say we have two spotted frogs, one from locale 1 and one from locale 2. These frogs would never breed in nature so why should we intermix them simply based on outward appearance. I guess the point I’m trying to make is that to me, location seems to be the only way to determine what frogs should be bred"
> 
> Yes but in the case where the locality is unknown then the closest we can come is to frogs that came into the country in the same importation.


So we are trying to breed based on locality info that is missing or incorrect. It seems all of the new imports are not giving locality info due to smuggling concerns which leaves us in the same situation. Too bad there isn't away to get around this, i think it would really help the hobby. Stupid smugglers. 



Ed said:


> snip "I think I read somewhere that azureus come from a very small area in Surinam. If I remember correctly, it was an area the size of a football field. If this info is true, there is only one population in the wild and any member of that population should be able to breed with any other member"
> 
> They come from primary forest remnants on one slope in the Sipaliwini region. The remnants can be as small as a foot ball field but can also be much larger.
> 
> Ed


So habitat destruction has divided the population into several sub-populations that no longer intermix? I guess that would make it tough to decide if there should be different morphs due to the fact than an un-natural process may have caused them to occur. Or are all of the wild populations still the same and the different patterns simply products of what the hobbyists have bred?


----------



## npaull (May 8, 2005)

I am against crossing morphs that we know to be geographically distinct and more or less isolated genetically from other morphs. I personally have zero problem breeding different lines from the same locality, assuming we have that data. My mind is not made up on how I feel about breeding different lines of the same "morph," absent locality data (ie breeding an unknown line of standard imitator to another); I'm inclined for the present not to be too neurotic about it. 

I would *guess* that with a species exhibiting as much phenotypic plasticity as imitator, "morphs" that look identical may well have the same locality, or near enough as to make "no difference." Again, that is a guess, and a part of the reason for my above-stated uncertainty. 

The whole idea that we can somehow know or understand how to emulate "natural" gene flow and genetic drift in captivity I feel is a little absurd, especially because ALL of the animals in captivity are completely removed from all evolutionary forces experienced by wild populations - relevantly, including gene flow among populations. The very act of captive maintenance and propagation through multiple generations, then, seems to me more likely to affect the genetic makeup of these animals (compared to their wild counterparts) than does crossing different lines of the same morph, especially because we know for a fact that more significant outcrossing most likely occurrs within a morph in a given locality.

All that said, I think the fears over inbreeding are too hyped. I posted this somewhere else, but I forget where, so I'll reiterate briefly... ALL LIVING THINGS ARE INBRED. And most living things are vastly more inbred than we'd guess, including humans. Most human beings of the same geographic origin (ie European, native american, african, etc) are related to eachother fewer than 20 generations ago, usually much fewer. It's a mathematical fact - every individual has 2 parents, 4 grandparents, etc. So at generation n, you have 2 to the power n ancestors. That number gets ridiculously large very quickly, vastly larger than the total population at that time of the species in question. The answer is two-fold 1) some relatives are "relatives" many times over, and 2) not all the ancestors are distinct. The upshot is that we're all related. With organisms that have small wild populations (and most dart frogs do, relatively) the "relatedness" is bound to be much higher. 

My $.02.


----------



## Ed (Sep 19, 2004)

snip "The whole idea that we can somehow know or understand how to emulate "natural" gene flow and genetic drift in captivity I feel is a little absurd, especially because ALL of the animals in captivity are completely removed from all evolutionary forces experienced by wild populations -"endsnip 

This is true. and the only way we can deal with this is try to maintain maximal representation of the gene pool within the population. If there are two different breeders that have maintained for example the Sens line imitator for multiple generations, the allele segregation will likely have diverged to some extent and these frogs should be identified and crossed back to one another to maintain maximal gene representation within the captive population. This is difficult to accomplish in practice as the frogs under go waves of popularity and people dump lines and move onto the new frog reducing the overall gentic diversity in the population. Then the frog becomes fashionable again and the few people who held onto the stock resupply the hobby; however with each cycle the frogs become more and more gentically the same which over time can cause the fitness of the group to decline. 



snip "The very act of captive maintenance and propagation through multiple generations, then, seems to me more likely to affect the genetic makeup of these animals (compared to their wild counterparts) than does crossing different lines of the same morph, especially because we know for a fact that more significant outcrossing most likely occurrs within a morph in a given locality. "endsnip 

How do we know that the crossing of a morph is a less significant outcrossing that what can occur within a morph at a given locality? 

Given the disjunct range of imitator, there is a significant chance that crossing the different lines would result in the crossing of disparate locality frogs. 

One of my biggest concerns with the dendrobatid group is that we are placing a large evolutionary pressure on the frogs to drop the parental care of the eggs/tads in the non-egg feeders are very few people allow the frogs to care for the eggs and deposit the tadpoles. 


snip "All that said, I think the fears over inbreeding are too hyped. I posted this somewhere else, but I forget where, so I'll reiterate briefly... ALL LIVING THINGS ARE INBRED. " 

This maybe true but the deleterious effects are swamped out in a natural population due to the frequency of the alleles and the selection for survival. In a small population without any evolutionary pressures selecting for survivial fitness, the segregation of deleterious alleles can be accelerated leading to a decline and loss of that population... 

Ed


----------



## Ed (Sep 19, 2004)

Re azureus 

snip "So habitat destruction has divided the population into several sub-populations that no longer intermix? I guess that would make it tough to decide if there should be different morphs due to the fact than an un-natural process may have caused them to occur. Or are all of the wild populations still the same and the different patterns simply products of what the hobbyists have bred?" endsnip 

I don't know as I haven't been to the site to see nor have I asked anyone who has been there. There may be linked corridors or other pathways that allow for gene flow between the sections however I suspect that this is a relatively recent artifact. 
You have to keep in mind that azureus has not been imported for 20 years or so and all of the different variations in spotting, etc have only been bred well after that period. 

snip "So we are trying to breed based on locality info that is missing or incorrect. It seems all of the new imports are not giving locality info due to smuggling concerns which leaves us in the same situation. Too bad there isn't away to get around this, i think it would really help the hobby. Stupid smugglers. " endsnip 

But some of the import like those coming from Understory should have identification numbers which can be used to tie them together without divulging locality data. The INBICO frogs should have some other form of documentation as they were all cb and not collected. 


Ed


----------



## npaull (May 8, 2005)

> How do we know that the crossing of a morph is a less significant outcrossing that what can occur within a morph at a given locality?
> 
> Given the disjunct range of imitator, there is a significant chance that crossing the different lines would result in the crossing of disparate locality frogs.


Ed, to be sure, we do not, but I would assume that a larger gene pool (for certain species, like imitator) within a given locality in the wild would provide for more genetic diversity than can be had in captivity. I wasn't clear - I wasn't talking about crossing morphs, but rather outcrossing lines within a morph, and saying that (given 1 morph, 1 locality) more significant outcrossing within that group occurs in the wild than in captivity, given the richer gene pool.

I agree with your concerns about inbreeding; I don't advocate it, but I do think it may be less of a problem than it is made out to be.

I am curious as to why you think we are placing selective pressure on frogs against parental care. Does removing eggs from frogs who would otherwise provide for their tadpoles decrease their genetic contribution to the captive pool? In other words, are frogs that "don't care" for their tadpoles doing better in captivity than those that do not? I cannot see how that would be... the only way to lose these behaviors via evolution would be to decrease the genetic contributions of "care takers" relative to the "non care takers" in captivity. Given that the choice whether or not to rear tads is removed from the frogs (and given to their keepers) I am not clear how/if this is happening. Might removing eggs from parents that would feed their tads in fact free up these same parents to have more offspring (ie, spreading the trait?) I suppose, conversely, that if we do not "wait and see" which frogs can/can't rear tads, we are giving those individuals with poor parenting skills an equal shot... I think I see what you mean, now, but I don't believe we are selecting against parenting skills.


----------



## Ed (Sep 19, 2004)

My fault for misunderstanding. 

Snip "I am curious as to why you think we are placing selective pressure on frogs against parental care. Does removing eggs from frogs who would otherwise provide for their tadpoles decrease their genetic contribution to the captive pool? In other words, are frogs that "don't care" for their tadpoles doing better in captivity than those that do not? I cannot see how that would be... the only way to lose these behaviors via evolution would be to decrease the genetic contributions of "care takers" relative to the "non care takers" in captivity. Given that the choice whether or not to rear tads is removed from the frogs (and given to their keepers) I am not clear how/if" endsnip

Egg rearing and tadpole placement are energetically expensive and are coded by a set of alleles. If we are pulling the eggs and not allowing the frogs to rear them, then we have not only removed the selective pressure to maintain the frogs as good parents but we are inducing a bias for those frogs that make no attempt to care for the eggs and divert all of thier resources to producing the next clutch of eggs. If the male is diverting his care to the eggs then he is diverting calories and time that could be spent convincing the female/females to lay more eggs. If you have a male that ignores the eggs once they are laid then that frog is diverting more resources to producing the next generation....

In E.O.Wilson's Sociobiology book there is a better explination as well as some statistics which explain it better than I ever can.. 

Ed


----------



## npaull (May 8, 2005)

> Egg rearing and tadpole placement are energetically expensive and are coded by a set of alleles. If we are pulling the eggs and not allowing the frogs to rear them, then we have not only removed the selective pressure to maintain the frogs as good parents but we are inducing a bias for those frogs that make no attempt to care for the eggs and divert all of thier resources to producing the next clutch of eggs. If the male is diverting his care to the eggs then he is diverting calories and time that could be spent convincing the female/females to lay more eggs. If you have a male that ignores the eggs once they are laid then that frog is diverting more resources to producing the next generation....


Ed, I agree that pulling eggs to rear tads removes must remove selective pressure to maintain parenting behaviors. I do not see the inducement of "a bias for those frogs that make no attempt to care for the eggs" as clearly. I can, however, see a problem arising from the "level playing field" between care-takers and non-care-takers, allowing for bad parents to have more offspring than they otherwise would, thereby diluting the pool of good parents.

Experience tells us that pulling eggs usually causes parents to begin the breeding/laying process again. However, it would seem that, in order to introduce a true bias *against* parenting behaviors, one would have to assume that "bad parents" are going to be better at rapidly restarting the breeding process, thereby yielding more eggs for their keepers to rear, thus producing more offspring, and gradually spreading throughout the hobby. This is doesn't seem to be an unreasonable hypothesis, but I do not see why bad parents would necessarily be better at breeding again than good parents, faced with the same situation of a pulled clutch. If both bad parents and good parents can replace pulled eggs at the same rate, then we have removed a positive selective pressure for parenting, but not introduced a negative one in its place. What do you think?

Thanks for your insightful comments. I really enjoy discussing these kinds of things with you.


----------



## Ed (Sep 19, 2004)

snip "I do not see the inducement of "a bias for those frogs that make no attempt to care for the eggs" as clearly. I can, however, see a problem arising from the "level playing field" between care-takers and non-care-takers, allowing for bad parents to have more offspring than they otherwise would, thereby diluting the pool of good parents. 

Experience tells us that pulling eggs usually causes parents to begin the breeding/laying process again. However, it would seem that, in order to introduce a true bias *against* parenting behaviors, one would have to assume that "bad parents" are going to be better at rapidly restarting the breeding process, thereby yielding more eggs for their keepers to rear, thus producing more offspring, and gradually spreading throughout "


In the second paragraph, you have hit the nail on the head. Frogs that do not parental rear will restart the breeding process faster than those that do rear. As the most simplistic model, as soon as the first clutch is laid, the frogs are proceeding onto the second clutch while in the meantime, there is a time delay for the parental rearing frogs while they (so I don't type male/female caretaker) care for the eggs until they are pulled... This is a small but significant difference over the life of the frog given the level playing field for survival of the tadpoles will cause those that do not parental rear to have more surviving offspring leading to an incease in thier gene amplification with each suceeding generation... 
This can have a bigger impact as you only need to change the behavior of one of the sexes to cause this result. In frogs where the male is the caretaker, being able to ignore eggs and move onto the next female and the next female is a significant advantage... 

Just some thoughts,

Ed


----------



## npaull (May 8, 2005)

Ed,

A good, thoughtful analysis. I agree, and see your point clearly now. I for one prefer to let my parents rear their own tads; hopefully more and more emphasis will be placed on encouraging natural behaviors in the future.


----------



## Ed (Sep 19, 2004)

As an afterthought, this doesn't mean that the frog has to rear all of its eggs/tadpoles but it would be nice to have people test out some of the clutches to see how they do and to some extent use these as thier breeders.... 

Ed


----------

