Inter-species breeding

I must disagree or at least ammend #2 of youre post
I believe captive bred being released for increasing the #s of wild populations in decline are perfectly fine if there locale specific and I mean stock origonating within say 10 miles of their release point,bred/ raised withought any contact with any non locale animals and under all permits that may apply.

Jeremiah Ronsonet
Diablo Snake Farm

If i remeber correctly , mother nature has provided some species with crossing boundries with others that will allow "mutts" to be produced in the wild . Hogg Island boas in their native insular habitat would have inbred themselves to death if not for the fact that other boas had washed up on the island to throw fresh DNA into the mix .

What some people are doing is wayyyy out of touch with the plans momma nature had intended . My boss is trying to figure out how to cross a King Cobra with an Anaconda. Never happen but as long as people have these ideas and intentions it will eventually happen . As long as the crosses are advertised properly i see no problem with it . Some species will eventually need to be outcrossed to a similar species for fresh DNA anyways . Can only breed Hoggs for so long before they are all brothers and sisters.

No idea if i made any snse as i've been painting all day and am kinda woozy.

Bryon

Inbreeding unto itself does not automatically cause problems, it merely strengthens the existing genes...

While this can occassionally cause negative traits inherent in the gene pool to rise to the surface as sucessive generations reinforce minor traits until they become major ones... The situation in the wild is very different than the situation in captivity. In the wild, animals which are less able to survive never get a chance to enter the gene pool, removing those negative genes from the population. In captivity, we've removed the process of natural selection, far too few people will properly cull their clutches, allowing minor negative traits to become major ones in a FEW instances.

Basically, wild populations of animals can't "inbreed to death", it's simply not possible.

It's really comparatively easy to get something INTO a captive gene pool, all it takes is shoving two snakes together (An oversimplification perhaps but not entirely untrue, the snakes do the real work). Getting something OUT os a gene pool is nearly impossible.

Take, as an example Creamcicle corns... How many people who own them do you think know how the "morph" was created?

How many well intentioned but basically ignorant owners have you seen who have big ideas about how they'll breed snakes by crossing the two that they happen to have avaliable... Or those that don't understand how the pigments and the genetics work who want to cross their creamcicle with their lavender to "see what happens"?

If they succeed... and there isn't much preventing them, corns aren't exactly a tough breeding project, merely a tough breeding project to do the right way... Do you think that they will represent their offspring as being 75-25 hybrids? How many of the big broker companies purchase animals from just about anyone, only to mix them up, send them out and get them resold?

It's bad enough when you can't buy two normal looking cornsnakes from most sources and breed them without getting a grab bag of ugly pigment-lacking-mutants... Now people will need to worry about having cal king genes in there too.

So far I have not seen any arguments presented that really validate hybridization, the best people can come up with is "dey look kool!!!111" or "Hey, I can breed my ten dollar corn to my ten dollar cal king and sell the offspring for eighty bucks to people who don't know any better." whereas the arguments against hybridization include genetic contamination, questions about long term health effects and a legitimate danger to wild populations.

Originally Posted by diablohogs

to prevent being catogoriezed as a troller i guess i'll have to explain my stand on this issue.

1. crossing two genetically different snakes and producing hybrids in no way effects the genetic makeup of said parents. therefore preserving thier genetic makeup.

2. any captive bred animal has no buisness being reintroduced to the wild hense they effect the ecosystem's gene pool in no way.

3. we are talking about an industry ( the pet industry) where personality and asthetics are the traits the consumers look for. in most cases a locale specific or pure bred animal will sell for more. and if you are truely concerned about being lied to than goto a reputible breeder that prides themselves on purebreeds they're everywhere... i.g. this forum.

4. every captive animal will die. weather it is pure or not. if people are so concerned about saving pure genetics than you need to get activly involved with habitat preservation. heck, sell hybrids to fund your trips to these places where these pure snakes inhabit and make a real stand.

5. i feel snakes need to be reclassified using modern science technology. there are ways to have the genes checked on birds and dogs for the breeders of those animals. why not genetically reclassify all snakes starting with colubridae?!

6. in a case where you have a rare or protected snake in captivity ( i'm guessing legally), you should have bought 1.1 so you can repopulate (the pet industry? cause what are you gonna do... let em go in the wild?) with said animal. or better yet boycott the purchase of rare snakes to prevent people from catching them in the wild for profit ( i'm sure these rare snakes you speak of arn't cheap) thus lowering the wild population even further.

thanks,
chad elmore
diablo snake farm
http://www.diablosnakefarm.com

now if you actually read that is all makes sense. and i greatly thank this person for taking the words out of my mouth! read all of that it he has found every good point about the topic! every good point! nothing is being destroyed!! wow i love whoever wrote this! it couldnt have been said in a better way! thank you DIABLOHOGS!

Originally Posted by Glenn Bartley

Were the offspring able to reproduce or were they mules? (Although I recently heard it reported that a real mule has reproduced). And what about inter-genera breedings?

As for me I think it is ok, so long as it is not producing absolute freaks like snakes with deformities. I think that such would be a help to geneticists, and possibly advance scientific and medical research.

Hi,

Some mules have proven fertile. All of them males, last I heard. In another post, possibly in one of the other threads, someone mentioned this is due to different chromosome numbers in the parental species. This is likely not the direct cause since other species with different haploid numbers have consistently been able to produce fertile offspring. In fact I believe it is fairly common in waterfowl.

With mules the primary cause of infertility is that homologous pairing does not occur, or if it does it seems to be due to little more than random chance.

As most know, a mule is from a cross between a female horse (diploid chromosome # = 64) and a male donkey (diploid chromosome # = 62). So each contributes 32 and 31 chromosomes to the hybrid offspring respectively.

When gametes (sperm or eggs) are produced within each of these hybrids there is no homologous pairing during meiosis. So some gametes could, hypotheticaly, end up with zero chromosomes, others with 63. I don't know if either of those extremes have actually been documented, but I say them to make a point.

So it is an issue of chromosome number, but not necessarily the parental diploid numbers as was presented in another post.

As I said early, other species with different diploid numbers have been able to consisently produce fertile offpspring.

But to get to snakes, it does appear that interspecific and even intergeneric hybrids are usually fertile.

Many have mentioned that this should lead to reclassification or that it somehow contradicts long-standing scientific principles. I believe what these people are getting at is the Biological Species Concept which suggests that if two sexually reproducing organisms can produce fertile offspring they are the same species.

What people need to know is that this was always a criticized species concept from its onset. It has maintained a strong presence in textbooks simply because it was and still is a useful way to get students to think about what a species is, or more importantly, what a species is not. Unfortunately most of our junior and high school teaches went on to teach this as a widely accepted species concept and taught it as fact.

With our current understanding of reproductive biology what we know is that the issue is reproductive isolation, or what prevents two organims from reproducing in the wild. In the case of snakes there was likely little pressure on them to develop reproductive mechanisms that would prevent them from breeding with other species. Reproductive isolation can be seasonal, temporal, pre-copulatory, post copulatory, just to name a few. To cut this post short, modern science simply does not emphasize one type of reproductive isolation over another when classifying species. The ability of two species to create offspring in captivity, fertile or otherwise, simple has little effect on our perception of how closely they are related.

The one issue snake hybridization does effect in science is the long-standing assumption that hemipenal variation is a form of reproductive isolation. Older papers do write of this assumption. But with all of the bizzare hybrids in the snake world scientists have now considered that hemipenal variation is less important as a means of reproductive isolation and is more important in the role of sexual competition. So in that regard science has appreciated and paid attention to the hybridization events that have occurred in captivity.

Hope this helps and that it's not to vague relative to this particular thread. I'm sort of addressing generalizations I read in at least three different threads on this particular forum.