out crossing, how long can it last?

In another thread i started to go on about genetics and deformities. However that thread was about a bad egg, not genetics. I feel a new thread should go up for that. I dont believe a discussion like this has been brought up since I've been here. The point I was getting at, is that if we continue to out cross from different breeders, yet have lines go back and forth from each one, how long can we do it before alot of the lines become more and more genetically similar and genetic defects occur more and more? I see threads here all the time about someone getting something from Kelli, Dan or Marcia. You guys go back and forth exchanging animals to get new lines brought in. But how does that work. Heres an example. Marcia buys gecko A from Kelli. She buys gecko B from Dan. She breeds geckos A and B not only to each other but to a few other of the breeders she has. Next season, Dan and Kelli both come to marcia perhaps seeing an animal they like or maybe to outcross their own lines. Do you see what I'm getting at? The lines are going back to each other. I'll take it a step further. Instead of going to Dan or Kelli from Marcia, it instead goes to Albey or Alex Hue. But maybe they already have some of Kellis or Dans animals? So they breed that animal to theres. Now Kelli or Dan goes to Albey or Alex, buys a baby that was essentially produced from their lines in the first place and along with its siblings is passing down the same "inbred" genes. This was just an example. I don't know how you guys do things when it comes to this but its something I thought of off hand. Its soemthing I've been thinking about for awhile now. Maybe its driven by the fact that I'd eventually like to see some WC leos to maybe eventually get a T- albino. But unti lthen we ahve to rely on all the genes in the giant communal swimming pool we have. All opinions welcome here no matter how it is.

I'm not a leo person, but I'll toss out a few comments here. Leopard geckos were (I believe) the first lizard consistently reproduced in captivity. Regarding your comment about desiring to see some WC leos: I don't know if they are still being imported...but when we had the shop (7-8 yrs ago), I saw many that I suspected/believed were. Outcrossing obviously does not have to be with WC blood, but the goal is to add genetic diversity to a colony. Toward that end, there may be some discussion of lineage when the handfuls of upper echelon breeders purchase from, or trade with, each other. Of course when working with morphs, the easiest form of outcrossing is to breed back to wild type (normal). Sure, it adds time to projects, and decreases the monetary return, but it adds the genetic strength you seem to be concerned about. And there are certainly enough breeders (at many different levels) out there to provide new blood to any colony.
Please keep in mind that I do not deal with leos, and do not know the breeders or their practices...my comments are nothing more than common sense applied to the concern you expressed.

so - in answer to your question (funny how I forgot that in my first post): outcrossing can, and should last forever. Even without considering WC specimens to add new blood, there is enough diversity in the US to provide a self-sustaining, genetically diverse population...all you have to do is utilize it. And if that gets boring, or seems like too much trouble, there are always imports from non-US populations (ie. Europe, Canada, etc)

Thats what I was getting at. I'm just wondering if that we will in fact eventually be unable to outcross without there being some form of relation there. Remember, these geckos go across the country and everywhere in between. More people get the bloodline, perpetuate the trait and sell the off sring.

Look at it this way (I'm gonna take you into my world for a moment) - No WC Jungle Carpet pythons have been imported to the US for years, simply because they are not being exported from Australia. There wasn't a huge population here when exportation stopped, but there is now. Sure, occasionally, some new blood finds it way to us from overseas, or canada, or who knows where (including even the occasional smuggled specimens in years past)...but it is essentially self sustaining. The base population was small enough that one could easily argue that there is some degree of relationship in any random sampling. There were the big names that dealt heavily with them and produced some of the finest specimens seen; and many smaller names mixed and matched those bloodlines AND - here's the key - some average, or even below average looking ones that they got from random other places. IF there is a closed population (no imports from anywhere), and the big names buy only from each other, and they are so desired that everybody else buys only from them, and everybody is so morph-minded that they strive to keep everything as "pure" as possible (by which I mean that they only breed this phase to this phase, and that morph to that morph; never mixing and matching, or outcrossing to wild type) then the problems you fear will come to be. BUT, it isn't likely to happen. There are hobbiests that have never even heard of the big names, that get their leos from PetCo and a couple of people in the local herp group. They have some normals, maybe an albino, or some other commonplace, reasonably priced morph; and they breed them together. They sell some to the petstore, maybe trade a few, who knows...maybe they even go to a show a few towns over and do some trading there (disseminating the blood, AND bringing in new stuff). These aren't top dollar animals, but they are healthy...and they will sustain the population because people will breed them. They will be bred because they are out there, because they are what people have, because they are the ticket/stepping stone to fancier animals. People will scrimp and save and purchase that hi-dollar gecko, and breed it with something they have...working the "plain jane" blood into the fancy population. Piebald ball pythons are a good example of this. A simple recessive trait...a very expensive simple recessive trait. The average Joe can't afford to buy a pair, so he buys a het and breeds it with a normal. He breeds the babies back to the het parent. Then he buys a few possible het females and breeds them to what he has. Sometimes it works, sometimes it doesn't; but the blood is mixing...and it will mix in the same way with leos. That doesn't mean that your concerns are unfounded - look at some of the problems in the snake world that have come about because people choose to take the shortcut to the money (the eye issues that pop up in albino boas, for example) - just that the issues can be avoided/controlled with just a little bit of patience and common sense. (I apologize for the length...I guess I got carried away)

Thanks Harald, great post. Another example is the jungle/stripe line of geckos. To my knowledge Tremper was the first one, thru selective line breeding to produce these All of the variations floating around out there since the early 90s are descended from Ron's animals - bolds, redstripes... on and on.

its ok, lenght means detail and detail is good. its jsut something that ive thought about here and there.

Originally Posted by Dan Lubinsky

Thanks Harald, great post. Another example is the jungle/stripe line of geckos. To my knowledge Tremper was the first one, thru selective line breeding to produce these All of the variations floating around out there since the early 90s are descended from Ron's animals - bolds, redstripes... on and on.

Hey Dan, are you sure about the redstripes? On HQR's site it says,

"Early in our 1999 season of Leopard Gecko breeding we were surprised to hatch our first striped/jungle babies out of normal looking parents".

......although it does say later that these geckos were breed to a "full striped male Leopard Gecko from a well known breeder".

wayne

Thanks, Dan. I would have preferred to throw in some leo morphs as examples, but I've never made any claims to knowing the market or having more than cursory experience with the animals. You guys would have seen through my weak effort to look as if I knew what I was talking about, and that would have detracted from the rest of what I was trying to say. Thanks for letting me hang in your playground, but I'm going back to my little snake world now. Oh, before I go...Hi Shannan

Ron had Tangerine Stripes YEARS ago, from my understanding. And just go take a look at his Eclipse/RAPTOR page. The 'Eclipse' are NICE, very much like Red Stripes. Sure Matt & Susan have done the work to establish the "Red Stripe" line, but I think all genetic-stripe lines are descended from Rons line, like Dan was saying.