They are beautiful!
I will have to research assist feeding, just in case. I have heard it mentioned a few times but never seen exactly how it’s done. Doesn’t sound fun, but you gotta do what you gotta do when you love your animals!
Oh my goodness, that Halloween picture is so adorable! Nice job with the pumpkin, first off. And the snakes are the icing on that cake, to mix my metaphors horribly. Lol
True. The fingerprints of identical twins are similar but not identical. Identicals aren’t truly identical. Some twins are closer to it than others, but no individual is exactly, precisely like any other. Which is rather fascinating, when you think about it.
Slight differences in pattern don’t mean they’re not genetically identical. There are always differences, as mentioned above. Sometimes they’re very subtle, sometimes they’re easier to see. The genes present in an individual are called its genotype. The visible expression of these genes is called the phenotype. Identical siblings have identical genotypes, but some differences in phenotype. And yes, there are known environmental causes for certain phenotypical expressions.
You have exactly the right idea. 
And there’s a whole field of study called epigenetics which explores the relationships between genetic expression and the environment.
Your experience with twins is fascinating! I’m curious, did you do anything differently in your 2020 season? Different temps, different supplements for your females, different light exposure, anything you recall?
Mainly I just was able to get more females in my small collection to lay in 2020. A lot of years I only have 2 to 6 clutches. I only came to realize twins aren’t that common in most collections in the last few years. I think the rate I was seeing was always way more than normal, just partially lucky in 2020.
Really wishing I had kept actual records. Other than the GHI twins and a pastel GHI sister of theirs I have some other females descendant from the mom of the original 2000 clutch but I can’t be sure if any of those lines have recently had twins. I know I didn’t keep any of the 2020 twin moms. The remaining females may well have lost the apparent gene for cells that don’t stick together well enough.
I also haven’t kept males much as I’m usually buying males to get new genes so I don’t really know that it couldn’t have been passed through males, it just worked out that I haven’t really tried. I try really hard to avoid any inbreeding so that is another reason I haven’t used many holdback males.
Very interesting. I wonder what was going on with your girls, especially in 2020 lol. ( BTW Fraternal twinning is the direct result of things that happen solely in a female’s reproductive tract. Males don’t affect this; their sperm is either available or not for fertilization and that’s it. That said, it makes sense to question if a male from a line with a higher incidence of multiples might sire females who are more likely to produce multiples. I think that jury is still out. 
) I find the whole topic fascinating. I know, it shows. 
I’m assuming mine are identical twins as have always been same morph combo since I started producing morph combos.
Maybe I’ll produce a male worth holding back from the twin line and I can breed him to one of my non twin lines (without inbreeding) and see if twins start popping up there. I’m assuming it’s a single dominant type gene and of course it’s pretty hit or miss so I might not want to dedicate enough breedings to see if the male got it.
It’s still happening rarely enough that I’ve never had two sets of twins in the same clutch. Really should start keeping records as not even sure same female has produced multiple sets over a maybe 6 clutch tenure.
So many visual projects to catch up on not sure it will work out that I can dedicate many breedings to a twin project that frankly is a bit of a pain when it happens due to extra small babies.
One of the GHI twins is being paired with a mahogany likely het pied as is her pastel GHI sister. The other with a chocolate het hypo ph desert ghost. I do need a holdback male GHI mahogany and a chocolate het desert ghost so if a nice enough one of either hatches I can keep him. But unless he just happens to be a twin no telling if he got the gene.
I suspect that the tendency to produce multiples is more complex than a single gene. If it weren’t, I think it would be much more common than it is. I feel your pain, for sure. There are always more projects and potential projects in my head than I can possibly find hours or space to do. 
If you do hang onto a male, I’d be interested to see what happens with his offspring. I’m doing that in my corn snake collection as well. I kept the 2022 male twin produced by my twin female. Got a couple of female holdbacks from that clutch, too. We’ll see what happens.
I’m just basing the single gene idea on how resilient it has been in my collection without inbreeding. The GHI twins are great granddaughters of the mom from my original 2000 twin clutch. One of the 2020 moms was from that 2000 clutch but the other three were also around the 3rd generation or so. I do have quite a few other granddaughters and great granddaughters still but thinking they may be from branches that have lost the twin gene. Will try to keep better track of it going forward.
I should also probably try to figure out if my next twins are connected in some way. Not sure what I should look for though and I don’t normally cut eggs open enough to really see anything for fear they will come out early without absorbing yolk.
There’s definitely a lot we don’t yet know. I’m the first to admit that what science accepts today may change tomorrow. This is especially true in fast-growing fields such as genetics.
The Washington State article cited is a small study, which is of course fine. The author looked at seven families, who had 19 pairs of twins among them. I found this especially interesting:
"Some geneticists say that there could be more than one single gene that controls cell-to-cell connections. And they think these genes may be involved at different times in early embryonic development. The evidence for this is that they have only found two types of families with familial MZ twinning. In some families, all the twin pairs had two chorions, because the embryo split very early. In other families, all the twin pairs had one chorion, because the split occurred later. There were no families in which some twin pairs had two chorions and other twin pairs had one chorion. "
The fact that there was consistency within the families is fascinating. It is indeed suggestive of a genetic component. The sample size is, however, too small to draw conclusions.
There’s some other interesting research on the idea here:
Of course, all of the above is related to humans. Extrapolation to snakes is fun, and makes intuitive sense. Scientifically? We know that there sooo much we don’t know. Lol
My personal favorite tidbit about multiples is that the nine banded armadillo almost always produces identical quadruplets. (And I thank God I’m not a nne-banded armadillo! 
)
I don’t cut either, but I was able to see by candling that there were two developing fetuses and two placental regions in Victory’s egg. No idea about membranes.
I had a second set of twins from completely different lines hatch in 2022, but they sadly didn’t survive. I didn’t know that pair was coming, but I’m going to scrutinize that female’s eggs carefully when she’s bred again.
I was wondering what I could look for in the ball python twin eggs to decide if they are one or the other type. Probably not the best lab animal due to taking about three years to grow. I suppose not enough unrelated twin sheds available to find the gene unless it’s already been identified in the human studies.
Thanks for that, @eaglereptiles ! I’ll definitely check that out. It’s well established that fraternal twinning in mammals (including us) has a genetic component. It makes sense that there one in other species but I didn’t realize anyone was actually researching it.
This continues to be incredibly fascinating and enlightening.
There is a lot for me to go through and unpack here and I am short on time today so it may have to wait until I have a minute or three to come up for air. I promise I will circle back
Ready to circle back yet?
And yes I know you said you won’t be back for another week or two just am reading through old threads lol
No twins from the one GHI twin that went or her pastel GHI non twin sister. I did get 1.2 holdbacks from those sisters. Will try not to breed them together though. Trying to grow the GHI mahogany het pied male quickly to breed to a couple of unrelated mahogany females so might test if males can pass the twin gene if he even got it from mom.