Inbreeding insects

[JumpingSpiderLady]

I found a female S. Carolina and (when they're old enough). I'd like to breed her with my male. She's a bit bigger than him, but I'm pretty sure they're siblings. It's my understanding that inbreeding is not much of an issue with insects. Thoughts?

 

[BobBarley]

For one generation it's probably fine, but I wouldn't do it for more than one generation.

 

[Hisserdude]

While inbreeding does not seem to bother most inverts, people claim that mantids are particularly sensitive to it, and people end up losing inbred stocks after a few generations. However, according to Orin's "Keeping the Praying Mantis", such failures are more likely due to decrease in interest and effort given to keeping said species, so really who knows.

 

[blacksheep998]

You should be fine with making that cross.

As others have said, invertebrates don't seem to suffer as many problems from inbreeding as vertebrates do. The only case I'm aware of where it's a problem is with some of the fancy breeds of dwarf freshwater shrimp. Inbreeding has resulted in some breeds having deformed shells and shortened lifespans. But most of those are the result of multiple generations of selecting a single sibling pair or very small group in an attempt to select for some interesting color mutation.

 

[JumpingSpiderLady]

Thanks everyone!

 

[Ceymann]

Not agreeing or disagreeing with what has been said above simply because I have no knowledge of the reasoning why inbreeding concerns are minimal for most inverts. I have a thirst for knowledge so does anyone or can anyone provide me a link to reasons why? not trying to prove the notion wrong or anything, just want to know on a genetic level why its so different.
thanks!

 

[Tenevanica]

From my knowledge inbreeding is only a huge problem in moths. You should be fine inbreeding mantids, though it is probably best to avoid doing it too much.

 

[BobBarley]

From my knowledge inbreeding is only a huge problem in moths. You should be fine inbreeding mantids, though it is probably best to avoid doing it too much.

Hm I wonder why in moths? What about inbreeding in butterflies?

 

[Tenevanica]

Hm I wonder why in moths? What about inbreeding in butterflies?

Not sure. It would make sense though!

Sites like Ovogram were created to exchange moth ova and prevent inbreeding. The same people tend to also raise butterflies, and their ova are often exchanged. I have no idea whether it's as much a problem as it is in moths though.

 

[Galapoheros]

I was listening to a doctor on TV a long time ago talk about genetics and inbreeding. He said people have gotten paranoid about it and claimed that there are problems with inbreeding when there is a bad gene involved that is passed on enough to cause problems in following generations. But if there are no or few deformities, it’s not something to worry about, made sense to me.

 

[Ceymann]

I was listening to a doctor on TV a long time ago talk about genetics and inbreeding. He said people have gotten paranoid about it and claimed that there are problems with inbreeding when there is a bad gene involved that is passed on enough to cause problems in following generations. But if there are no or few deformities, it’s not something to worry about, made sense to me.

This does make sense to a certain extent, however I don't think any insect/ T keeper is going to be able to determine if the breeders each have "bad" recessive alleles for the same trait or not, if they do, genetically, the resulting offspring would more than likely end up with a genetic disorder or compromised development. This may work with humans if genetic testing is performed before reproduction, but with insects and T's this really isn't feasible.
The only insects that obviously wouldn't have a problem are from the order Hymenoptera (bees, wasps, ants) as the males of the order are haploid (single set of chromosomes) and the females are diploid (two sets) which explains their success.
Still think there may need to be a be more research to determine if insects and and T's ( of which almost all both sexes are diploid except the Order I mentioned ) are subject to abnormalities and genetic disorders from inbreeding. Until such research and documentation has been done then, I guess we won't know?

 

[Python]

No expert here but I would assume that inbreeding wouldn't be as much of a problem in inverts for the same reason that they have so many offspring, high mortality rate. Combine that with the possibility of limited travel outside of a particular area (in some cases anyway) and it would appear that inbreeding would almost be a certainty in the wild.

It would seem to me that if inbreeding were inherintly detrimental there would haev to be some sort of safeguard to prevent it. Wide range dispersal would be the most obvious method of preventing inbreeding but considering there's no way to guarantee siblings won't disperse to the same area, that seems a bit dubious. Chemical deterrents, such as pheromones that would make siblings unattractive to each other, might work but there's no way to ensure more compatible mates in a given area.

With invertebrates producing so many offspring, inbreeding is bound to occur in nature, and probably commonly as well. That, and the fact that most inverts have a ridiculously high mortality rate would lead me to believe that inbreeding probably won't have a huge impact over the short term. Inverts are, after all, some of the most successful species on the planet.

 

[JumpingSpiderLady]

Being relatively new to keeping and studing arthropods, I don't have anything to add, but I've gotta say, I love an intellectually stimulating conversation! Especially when intelligent, informed individuals don't agree on all aspects. Really gets my mind working. I love this forum!

 

[Ceymann]

Being relatively new to keeping and studing arthropods, I don't have anything to add, but I've gotta say, I love an intellectually stimulating conversation! Especially when intelligent, informed individuals don't agree on all aspects. Really gets my mind working. I love this forum!

Exactly ! love discussing this type of stuff with other intelligent people, love that I found this forum in general, so many very intelligent, experienced and interesting users on here to interact with, pretty awesome.

 

[Galapoheros]

I like that aspect of it, I also sometimes think, “Wait a minute, it’s likely not that complicated in a practical sense.” You have one non-native gravid roach let loose in an environment it can survive in, that’s it, the species will probably be in that area for 1000s of years, interbreeding with siblings, bad mutations weeded out via natural selection, gene diversity established again over time. As a practical idea in the hobby, I wouldn’t worry about it other than not letting deformed specimens breed. There of course isn’t natural selection in captivity but because of the time and the likelihood of traits showing up “soon”, I don’t think it’s something to worry about. However, look at dog breeds, so many wouldn’t survive in nature and that didn’t take long. I started out with a few Hissers about 9 years ago and now have 1000s of them, I see nothing unusual so far.

 

[JumpingSpiderLady]

I was thinking about introduced species also. Like fire ants and Japanese beetles. Both introduced accidentally. Both all over my yard. Neither seems to be suffering.

 

[Python]

I have seen some interesting mutations in spiders but I can't chalk those mutations up to inbreeding, however, cultures of fruit flies with deformed wings (everyone is familiar with these) may be the result of inbreeding although I suspect that no one really knows the genetic history of them. I've never really looked into it to be honest. I can't say as I'm really familiar with very many other genetic defects, or any at the moment, that were caused specifically by inbreeding inverts. Throughout my time here, I've seen several threads dealing with this very subject and, if memory serves, consensus has been that inbreeding doesn't seem to affect inverts the same way that it affects animals of higher orders. I have seen many things change over the years and this could very well be one of those things and I missed it. considering the fact that the hobby is a fairly large one and most of the animals in the hobby are relatively easy to come by, I don't see a reason to inbreed short of scientific curiosity. If there is some ultra rare specimen that only has sibling examples, then sure, go for it. Otherwise, there's really not much to be gained. In the case of fire ants and Japanese beetles, I fear that inbreeding has caused them to become invulnerable, or at least nearly so. I sell chemicals used to combat such pests and even the restricted stuff seems to barely dent their numbers.

 

[BobBarley]

I chalk it up to inverts just being more "simple" than vertebrates and other animals. Not sure though.

 

[Ceymann]

I have seen some interesting mutations in spiders but I can't chalk those mutations up to inbreeding, however, cultures of fruit flies with deformed wings (everyone is familiar with these) may be the result of inbreeding although I suspect that no one really knows the genetic history of them. I've never really looked into it to be honest. I can't say as I'm really familiar with very many other genetic defects, or any at the moment, that were caused specifically by inbreeding inverts. Throughout my time here, I've seen several threads dealing with this very subject and, if memory serves, consensus has been that inbreeding doesn't seem to affect inverts the same way that it affects animals of higher orders. I have seen many things change over the years and this could very well be one of those things and I missed it. considering the fact that the hobby is a fairly large one and most of the animals in the hobby are relatively easy to come by, I don't see a reason to inbreed short of scientific curiosity. If there is some ultra rare specimen that only has sibling examples, then sure, go for it. Otherwise, there's really not much to be gained. In the case of fire ants and Japanese beetles, I fear that inbreeding has caused them to become invulnerable, or at least nearly so. I sell chemicals used to combat such pests and even the restricted stuff seems to barely dent their numbers.

Fruit flies are one of the staples of studying genetics, dealt with many using the punnett square approach to inherited genetics in zoology courses in college. I have no understanding of Japanese beetles, but the ants you mentioned, again, these are different, colonial insects typically have the females as dipoid and the males are haploid making any negative genetic conditions virtually impossible to pass on to young, therefore completely different to other insects when it comes to concerns of inbreeding, so there really isn't a case and point so far on the subject.

 

[JumpingSpiderLady]

In the case of fire ants and Japanese beetles, I fear that inbreeding has caused them to become invulnerable, or at least nearly so. I sell chemicals used to combat such pests and even the restricted stuff seems to barely dent their numbers.

Barely making a dent in thier numbers is key here. They are many. I kill Japanese beetles every day. (I'm a bit of a gardener.). But there will always be more. My methods are effective. Every beetle I encounter, dies. But they have so few predators, that thier numbers keep them going. Not to be argumentative, but inbreeding can't cause that.
Fire ants, I got no beef with.