Firstly, you need to seperate emotion from the equation if this topic is going to be debated, because it can be interesting, but it can quickly lead downhill.

Secondly, good luck trying to prove that inbreeding causes recessive or deleterious traits in invertebrates.

Thirdly, its not the act of hybridization that's irresponsible, it's the dispersal of the resulting offspring that's usually irresponsible.

For example: If I want to cross breed X with Y, what harm is it doing? Nothing. But, if I decide to give or sell the babies to anybody, even if they're correctly labeled, somewhere down the line there's going to be human error. It's inevitable.

If I keep all the babies, and rear them, and NONE of these babies ever see daylight outside of my spider room, what harm is it doing? Nothing. But, what happens when an unscrupulous breeder decides to sell the resulting hybrids as a new species? How are you going to know that its a lie? Well if its a Brachypelma hybrid, you're not going to know without a doubt for a good few years. The majority of people in the South African hobby can't identify their own pure bred spiders...now throw some hybrid new species into the equation...not good.

So as a summation, I think that like everything, theres a place for hybridisation experiments. The results can and should be documanted properly, and shared, but the product destroyed...or kept only as an ongoing experiment to check for sterility in the next generation.

Fourthly, hybridization occurs naturally in the wild between genetically similar species, occuring in a similar area. Ultimately this hybridization results in speciation. So essentially, by cross breeding, we're playing God and speeding up natural processes...but then by keeping animals in cages, we're playing God to a lesser degree anyway, so whats the big deal?

thank you all for your help, let us say that you do hybrid 8 generations of the same specie, what can go wrong?

Im no expert on inverts, but I don't believe their genetics works quite the same as vertebrates.

In vertebrate genetics, if two related offspring mate, you get a 'doubling' up of the same genes. This means there is a greater risk of offspring from those related parents having co-recessive genes. This does still happen in humans, even in 'non-related' people. Its why some lose their kids before birth multiple times, and why some child are born with problems (eg. Sickle Cell anemia).

In animals, more closely related species can cross-breed, often resulting in sterile offspring. If to lesser related species try mate, you often find incompatible genes and there is no fertilisation of the embryo.

I think ulitamtely, people don't have much information on what would happened if T are hybridised. Could you end up with more of the recessive genes in the hybrid (perhaps not co-recessive, but a loss of gene strength overall), or could you create something that outcompetes it's parents and causes two species losses?

I work in the biotech line. We can put the gene of an elephant into a daisy... But should we?

Bottom line, it's morals. and my 2c

@ArJay: I agree with a lot of which you say. All I want to add is forced evolution between two species which may have never crossed could have environmental impacts.

I also just want to state, I dont believe in picking sides on topics like this, as it often leads to unwanted debates, especially if there is already limited information on a topic. I realise my facts may seem skewed to a particular side, but this should be something each decides on their own, and accept people will have a difference of opinion.

I agree with Arjay and nightfang. but would like to add....
If you look at the orchid growers then you have people cultivating species and crosses made between species and even genera but they have a HOLY RESPECT for naming and labeling plants. so if i buy a plant i know exactly what it is...a species, a cross between x and y or xy's progeny and F. (i am not trying to go into the genetics but the consept of ethics and Responsibility). All the orchid people use latin names without arguing about it in forums! They all realise how detremental it will be if things get mixed up!! a R 1000 orchid without a lable is a R 90 pretty flower!

This is one of those "the Bell can not be unrung" issues! if we mess up our species then we are buggerd!! because they look so mutch alike and as was said elsewhere in the post that most people are so un knowledgable that very few of us can identify a species with sertainty!

and last but not least: i was standing in a conversation a while ago where people claimed that they know of people crosbreeding T species when they dont have males available and that SA red rumps are long ago no more pure bred!!! if that is so then it proves my point and What a pitty....because i bought them as red rumps.....wel they were red....just not Brachypelma vagans specie!!

I honestly believe that this hobby is by far to young to take on the responsibility to police itself and its members in this moral issue!! ......and where money is morals aint!!!

But that is only my opinion and an opinion is like a backside everybody has got one but they are al diverent!!

Please pardon the spelling errors!

Read this:

www.atshq.org/boards/viewtopic.php?f=3&t=27280

One thing to bear in mind with Theraposids and other similar organisms is that they are genetically capable of regenerating a whole population from one fertilised female, and this has most probably happened many times. They have kept their form very constant for millions of years, and only change when their environment changes. In order to accommodate this without the evils which accompany inbreeding in other orders, such as mammals, their genes are very conservative and have most probably discarded most possible deleterious gene combinations over the eons. If you do 100 generations of inbreeding of a single pair of T's I doubt that you would even approach the situation that we find in dogs - one species which has led to the chihuahua, the saluki and the chow. I do not think we will have much of a problem. Who is willing to set up the experiment? It should only take 30 years...