# pros of inbreeding??



## DendroRachel (Jun 21, 2011)

As a biologist, I understand the cons or inbreeding and the pros of out-breeding. After skimming all the inbreeding threads, the only pro for inbreeding I've found mentioned is that it keeps the line pure which eliminates uncertainty that both lines are from the same locale. 

I don't see the problem with breeding 2 frogs of the same morph, even if they are from a slightly different locale. Wouldn't it help diversify the bloodline and hopefully undo some of the inbreeding depression that was sure to have happened already in any line more than a few generations old? 

ps - I don't want to start a huge debate, just wondering why some people think it is better to keep a line pure?


----------



## mordoria (Jan 28, 2011)

I dont think thats the case. I think its more important to keep the morph pure. Also, I dont think anyone here will say they like the inbreeding. Most breeders I know try their hardest to use unrelated pairs.


----------



## Quaz (Nov 13, 2005)

I'm all for outcrossing within the same morph. ie. lets say you have a new cobalt import. I think the best thing to do is to cross them with a line that's been bred in captivity for years.


----------



## Ed (Sep 19, 2004)

DendroRachel said:


> As a biologist, I understand the cons or inbreeding and the pros of out-breeding. After skimming all the inbreeding threads, the only pro for inbreeding I've found mentioned is that it keeps the line pure which eliminates uncertainty that both lines are from the same locale.
> 
> I don't see the problem with breeding 2 frogs of the same morph, even if they are from a slightly different locale. Wouldn't it help diversify the bloodline and hopefully undo some of the inbreeding depression that was sure to have happened already in any line more than a few generations old?
> 
> ps - I don't want to start a huge debate, just wondering why some people think it is better to keep a line pure?


How about outbreeding depression as a con? In captive populations outbreeding depression is a significant concern and the current recommendations is to only look to out cross when inbreeding depression has rendered the situation dire. In anurans, even relatively close locations can have negative impacts when outcrossing between the two populations occurs (and this isn't even getting into the whole body of literature around salmon... There is a decent amount of literature documenting it. 

See for example 

http://www.environmental-expert.com/Files\6063\articles\5372\LV68M29432114864.pdf

Males with high genetic similarity to females sire more offspring in sperm competition in Peron's tree frog Litoria peronii

http://digilander.libero.it/lyrgus/Ficetola De Bernardi 2005 Animal Conservation.pdf

Crosses between frog populations reveal genetic divergence in larval life history at short geographical distance - ULLER - 2006 - Biological Journal of the Linnean Society - Wiley Online Library


and a review of the risks between inbreeding and outbreeding http://www.montana.edu/~wwwbi/staff/creel/bio480/edmands 2007.pdf

Ed


----------



## Mitch (Jun 18, 2010)

More siblings?


----------



## hypostatic (Apr 25, 2011)

So whats worse in the long run, inbreeding depression or outbreeding depression?


----------



## Ed (Sep 19, 2004)

hypostatic said:


> So whats worse in the long run, inbreeding depression or outbreeding depression?


 
The last link in my post should provide an indication of it in captive populations... I'll repost it here...see http://www.montana.edu/~wwwbi/staff/creel/bio480/edmands 2007.pdf 

Ed


----------



## DendroRachel (Jun 21, 2011)

Ed - thank you soooo much for the resources! I know its not easy to look up worth while articles for such a specific question. I was able to read over (although I admit not in entirety) all except for the Wiley article (needs a log-in). 

I think the subject can be summed up by this quote in Edmunds' Molecular Ecology article: "Managers are faced with very difficult decisions: promote hybridization to save populations from inbreeding depression, a phenomenon for which there is nearly universal evidence; or avoid hybridization for fear of inducing outbreeding depression, a phenomenon for which there is very scarce evidence"

I think that if we are very careful to avoid morph hybridization among the same species we should ('crosses fingers') be able to get some of the advantages of hybrid vigor and avoid outbreeding depression. I think the key to this is really in keeping morphs true - for example, not crossing highland and lowland r.lamasi. 

If we stress the importance of finding out and passing on all possible information (morph, line, locale) about our frogs we can help prevent damage from outbreeding. I'm really glad you posted all those sources Ed, I hope others read it as well so we can make our own educated decisions on the matter!


----------



## Ed (Sep 19, 2004)

DendroRachel said:


> Ed - thank you soooo much for the resources! I know its not easy to look up worth while articles for such a specific question. I was able to read over (although I admit not in entirety) all except for the Wiley article (needs a log-in).
> 
> I think the subject can be summed up by this quote in Edmunds' Molecular Ecology article: "Managers are faced with very difficult decisions: promote hybridization to save populations from inbreeding depression, a phenomenon for which there is nearly universal evidence; or avoid hybridization for fear of inducing outbreeding depression, a phenomenon for which there is very scarce evidence"
> 
> ...


Your welcome. I have to admit that I have most of those in hand already as I've had that discussion a lot on here (search outbreeding depression and select the post option instead of threads further down the page, and you can pull a lot of it up (if you want)) so it wasn't that hard of a task. 

Ed


----------

