Reptile & Amphibian Forums

It has been said that patterns "drift" away from the normal wild type pattern with every successive captive generation, even among locality specific snakes. I do believe this to be true and I believe I have seen this with my snakes as well. In my experience it seems males have a greater tendency than females do to "drift" away from the norm. Has anybody noticed this and if so why might that be? It seems that when I see a "classic" looking captive born Mexican kingsnake of any species, posted on the forums or classifieds, more often than not it is a female.

I don't know but I'll hazard a guess -

I believe the drift is caused because of different selection pressures. Natural selection in the wild, artificial selection in captivity.

I can't point to a locality line and specify the drift from WC but one possible explanation would be that males are generally used with multiple females, everyone and their cousin want 1.2 or 1.3 groups. As such, amongst breeders artificial selection pressure on males is greater than it is on females.

If there are any sexual dimoprhic phenotype tendencies (whether we have identified them them or not) the males would thus have more radical drift because fewer are selected to pass on their genes.
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I decided my old sig was too big.

"I can't point to a locality line and specify the drift from WC but one possible explanation would be that males are generally used with multiple females, everyone and their cousin want 1.2 or 1.3 groups. As such, amongst breeders artificial selection pressure on males is greater than it is on females."

I like it. Good thought.

I don't know Aaron.

but on another note. This 06 ruthie is gravid or so it appears. I had no plans to breed her, thinking she was too small. She went and ovulated anyway. Great but the 06 male is about half her size. Oh well, throw him in there anyway and see if he is big enough to do the deed. Well he did it, let's see if he is shooting blanks or not. Should find out in about three weeks.

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Herp Conservation Unlimited
Mexicana Group Directory
Photography by Joseph E. Forks

Joe I'm glad to see that snake is looking good. FYI it's a sibling to this guy, so maybe you will get some striped/abberrants too. I know myself, Shannon and a few others are now working with these and I expect alot of them will show up in the very near future.

This is a great question, but I am afraid their is no one answer. With kingsnakes, as least some types of kingsnakes, pattern migration is indeed evident. But it not so evident in other kinds of snakes or lizards.

I work with monitors, and some monitor species are so prone to a loose set of color or pattern, that is very difficult to line breed.

They tend to throw a range of colors and patterns in an effort that something will survive in a natural habitat that is constantly changing. An example is, most of the smaller monitors come from oz. Oz. is known for its extented droughts and wet years. It appears these monitors have found methods to cope with this variable weather. (not to be confused with a changing climate)

I mention those become some species of reptiles appear loose when it comes to this subject. That breaks us back to kingsnakes. We all know kingsnakes are "loose", that is, they have many pattern types within the same species. Also a wide range of colors and patterns in a givin local.

Let me get to the point, I believe with kingsnakes and varanids for that matter, color and pattern could very well be effected by enviornmental conditions. With small lizards this is very easy to see. I have examples if anyone cares to entertain them.

I published this many, OK, several decades ago. The example I used was; I had a pair of devils river alternas(exceptionally nice ones) that I personally collected, so I knew their actual history. I bred that pair for many years here in Tucson. They had a range of color type that I considered normal. Then I moved to Seattle(work at zoo) for a couple breeding seasons. There, the same pair had a totally different type of offspring. There offspring actually resembled another local. Then I move to New Orleans(again a zoo) for another couple breeding seasons, here the same exact pair threw an even different appearing offspring. Then I moved back to Tucson(heck with the zoos) then that pair threw its normal to Tucson type of offspring.

I had a unique set of circumstances that allowed me to see what conditions can do. We also know that incubation conditions can effect color and pattern before it adversely effects the health of the embryo.

So yes, as already mentioned, natural selection is a prime factor, and lets couple that with external varying conditions.

Also if you do some research, you will find that in many animals, including humans, there is some radomness in skin color, hair color and eye color. Of course, there is also genetic links, but again, some radomness.

For instance, a cloned animal often has different color and a different pattern then the individual it was cloned from. This sorta shocked me.

Lastly, color and pattern in reptiles is their quickest changing trait. As the enviornment changes and its constantly changing, both in the short term(weather) and the longterm(climate). The most obvious need for change is in this area.

Its very obvious that fires, floods, droughts, rain, all change the "look" of a local. These events occur very quickly, so in order to "stay current" these types of animals must have some tricks up their sleeve.

I believe a "loose" trait like color and pattern is a strong advantage for some species of reptiles. Not all, thats why there is no one answer.

Besides, its only humans and mainly ones in cities that think they are suppose to look a certain way. And all the time.(see, I really do have to say something rude) As my field partner said last night while we were out in the field. FR has taught me one thing, these animals "are what they are" not what we think or want them to be. Cheers and I hope this makes some sense.

At the risk of your disagreement, I shall say good post.

I agree with Tony.

I find your study with the alterna breedings extremely interesting. Did you happen to experiment with any different species or subspecies similarly to the alterna, and if so did you see any differences which may pssibly be able to be attributed to climate changes?
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Joe

Thanks Frank. I would have to agree with them trowing a range of colors. In my experience though having removed several snakes from the wild and placing them in a uniform captive environment, most of the babies strongly resemble their respective parents. Perhaps there is something that triggers plasticity more in some locations than others. I live in a coastal climate that is for the most part very mid-range, rarely gets over 85 and rarely gets below 40. Average temps in my house is probably 64-74 year round. When I have noticed departures from the norm it is usually more frequent in males and it is usually in the extreme in which they were already going. In other words dark parents produced darker babies, light parents produce lighter babies and snakes with red in them produced redder babies. When I have seen snakes in the classifieds, in particular thayeri and mex mex and I see one that very closely resembles a wild caught counterpart for which I have a photo, more often than not the captive born snake is a female. Rick Staub, in studying zonata has found that females move around alot less than males so I was wodering if males, having more propensity to move, may have more plastic genes where color and pattern is concerned.

poly paternity could offer a parial explanation in that for every females that lays a clutch the possibility exists that more than one male is also passing on genes for the same clutch.

In captivity generally we practice the reverse where groups are set up in ratios like 1.2, and 2.3; IMO there are many advantages to having male heavy breeding groups.
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Herp Conservation Unlimited
Mexicana Group Directory
Photography by Joseph E. Forks

A couple of things, to see migration in color a pattern, it takes a bit of time. As I mentioned with those alterna, for many years they produced what I thought was normal for them. Then I moved and changed conditions then all bets were off.

You do have to admit, tucson to Seattle, is a big change, Super hot to way cool. Then to new orleans, hot and humid and cold and humid. So it was not a little change.

Also about wild snakes, I am not sure I agree with Rick S. I do, without question, and not exactly how its being said.

We do find that females move very little. But when they are paired up, neither do their males. Lets call these a resident pair. Without question, there are many TRANSIENT males roaming all over heck. These individuals are soon to be predator poop. hahahahahahahahaha So yes, these males are very prone to predation.

With our resident pairs, we see the same male and the same female for decades with gilas and about 8 years(average) for colubrids and much longer for rattlesnakes.

The neat part is, we do see lots of variation in this resident/transient behavior, from local to local. Its my opinion, the same species can vary as much as different species, when they occur in seperate areas, like Mt. Kings. Cheers

kind of reminds me of a response to a similar post a while back. if a typical breeder has one male breeding 3 females (gene or genotype)in a drawer setup (times enviroment), sooner or later we will see newspaper corns, aspen kings and translucent sweaterbox milks ( equals phenotype, or maybe something like that...).
what would be really cool is if the newspaper corns could change their pattern to reflect the daily news, hahaha.

yeah, right.
daveb

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