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Originally Posted by Rich Z
Just answer a rather simple question for me Kevin. What exactly is mutation and what is it's assumed purpose within a species?
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It may be a simple question, but I'm afraid it doesn't necessarily have such a simple answer. New World Encyclopedia defines mutation as "a sudden change in the base pair sequence of the genetic material of a living organism, whether the genetic material be DNA or RNA. In multicellular organisms that reproduce sexually, mutations can be subdivided into germ line mutations, which can be passed on to descendants, and somatic mutations, which cannot be transmitted to descendants in animals."
Dictionary.com provides a more simplified applicable definition and calls mutation "a sudden departure from the parent type in one or more heritable characteristics, caused by a change in a gene or a chromosome." There are other definitions that are less applicable to biology specifically, but I think we all understand what mutation is in essence (at least in this case) though we might word it differently.
As far as the assumed purpose of mutation, there is none. Mutations are random though they might be caused by triggered specific factor such as incubation temperature for example. They are merely a change resulting in an organism and can be neutral, negative, or positive (though positive mutations are relatively rare). Changes in the color and pattern of corn snakes may fall into the neutral category since they don't harm the animals themselves in most cases unless they increase the risk of predation. There are examples of negative color/pattern mutations though, such as the calico or piebald corns that developed blisters in the white areas. There are also negative physical mutations such as lack of scales, two heads, serious kinks, etc.
Quote:
Originally Posted by elrojo
There is a difference between releasing an animal where it is native and where it is not. I have only released progeny of Okeetees I collected myself, and I know when I run across one! The drab local corns are getting a splash of color, is how I see it. Is that tampering? Perhaps, but enough survive that I find them again (and I don't release many, just poor feeders and extra males).
Turning iguanas and Burmese loose would be another matter, but releasing some healthy corn snakes in corn snake country doesn't sound like the worst offense in the world.
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Of course there is a difference in introducing a species or releasing captive animals within their natural range. That doesn't make the latter option any more wise though, just potentially less damaging. You've helped me make my point that many of the corns you released survived and you found them again in spite of the fact that they may be more brightly colored. If poor feeding has any genetic heritability, that could negatively affect the local population. Extra males would obviously tip the sex ratio in the area where they were released and those extra males eating the extra mice and anoles might limit the prey available for females that need to yolk their eggs. These are just examples off the top of my head of negative effects which could result from this practice. While it may not be "the worse offense in the world," as I said, it doesn't make it any more wise.
Quote:
Originally Posted by Rich Z
Nature works in strange ways. I don't think it takes a big chunk of imagination to make the conceptual link in how the pet trade is actually a symbiotic relationship. Carrying that thought a little further, it doesn't strain the brain muscles much to see that an animal that has a mutation that is attractive to humans could very well be a survival strategy at work.
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I don't think this would apply in very many cases at all. If your average uneducated snake hater sees a snake on the road, I doubt he'd be any less likely to kill it if it was yellow, striped, or lacking melanin.
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Originally Posted by wstphal
Personally, I can't see that releasing color morphs of cornsnakes in the normal wild range of corn snakes will do any harm. If they survive, they will contribute their genetics to the local population, but most color morphs are recessive so will be invisible. Serpenco snakes certainly wouldn't be carrying any CONTAGIOUS diseases that would hurt the local wild corn snakes. So no risk of carrying infection to wild FL cornsnakes. Probably most won't survive, some will. Corn snakes in the wild are probably prolific but very few survive, and I can't see how the released snakes are going to alter that dynamic much. They aren't an invasive species, they were released where corn snakes normally occur, so it's not like reticulated pythons or kudzu.
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OK, I'll try to address a few things here.
1. "If they survive, they will contribute their genetics to the local population, but most color morphs are recessive so will be invisible."
That would be a big part of the problem-they'd contribute their genes when/where they otherwise wouldn't. Does no one else understand there's a reason we don't have many naturally occurring corn morphs? Even if the morphs are recessive, those hets can and will produce more morphs. What if some amels hatch out and do very well, initially outcompeting other hatchlings due to their larger size and increased vigor from generations in captivity? These snakes might then be preyed upon heavily as adults due to being more visible. Those that survive would continue to pass on their genes, perpetuating the cycle and magnifying the problem (ultimately decreasing the corn population). Again, this is just hypothetical but there are so many possibilities, and I don't think any I've mentioned are especially unrealistic.
2. "Serpenco snakes certainly wouldn't be carrying any CONTAGIOUS diseases that would hurt the local wild corn snakes. So no risk of carrying infection to wild FL cornsnakes."
Sorry, but you have no data to back that up. Snakes can and do get ill. As many corns as Rich has, I'm sure some of them have had health issues. It's not necessarily any reflection on his husbandry, just statistics. If that wasn't the case, there'd be no need to quarantine any new acquisitions. The fact that Rich is an experienced big-name breeder doesn't somehow make all of his snakes flawlessly healthy.
3. "They aren't an invasive species, they were released where corn snakes normally occur, so it's not like reticulated pythons or kudzu."
Maybe not, but if there are 20 adult corns on Rich's property right now, there's a reason for that. It's balance and ecological dynamics. Here's another hypothetical scenario: If 20 new corns were released on his property when naturally there would only be 20, there would obviously be increased competition for food. This could obviously affect the corns. What about other rat snakes that are there like gray or yellow rats? They have similar diets and this influx of new hungry individuals might affect them too.
Quote:
Originally Posted by Rich Z
Sorry, but I just can't believe that anyone can seriously think that even if everyone now producing corn snakes released most of their stock into the wild, that it would have even the slightest impact when compared to the damage that mankind has done with habitat destruction and the MANY MANY animals killed on the highways annually. Not to mention that the habitat destruction normally involves the establishment in that area of a species of mammal that will often take a shovel to any corn snake that dared try to reclaim their ancestral homestead.
And there is also the consideration that mankind has also been instrumental in the establishment of fire ants through most of Florida, which has had a devastating impact on nearly all egg laying reptiles.
Yeah, releasing corn snakes is sure going to be devastating in comparison.....  |
I never said this would be the worst ecological problem ever, only that it has a very real chance of causing unforseen problems. You're absolutely right that human intervention and habitat destruction has been devastating to wild snake populations, and it's possible that your actions will not cause
as much damage down the road as these have. Why cause any damage at all though? Why not allow the snakes to exist without any further meddling? You may have a large cheering section now, but if your actions did cause problems of any considerable scale down the road, would it really be worth it because you as one individual enjoy finding atypical-looking corns on your property?
Again, I'm not trying to be offensive, just to increase awareness of the possible consequences of this decision. If you really think I'm being so irrational and jumping to far-fetched conclusions, I encourage you to occasionally check this post on the issue I made on another forum:
http://www.fieldherpforum.com/forum/...689ac693ceda55
I tried to word the thread in such a way as to minimize bias and protect your identity. There are no replies yet since I just posted it, so I don't know which side of the debate will be supported. That board is full of individuals from all walks of life, but includes quite a few academically trained ecologists, taxonomists, and biologists of various specialties. Hopefully there will be some very informative responses from those much more qualified than I am on this issue.
If you read nothing else in this post, note the following:
There's a reason tampering with ecosystems causes a chain of effects-it's a food
chain! Maybe the consequences aren't immediately obvious, but that certainly doesn't mean there won't be any.
I assume everyone here is familiar with the ecological disaster caused by Cane Toads in Australia. I'm NOT saying this is analogous to what Rich is doing because Cane Toads are a highly unpalatable, toxic predator introduced well outside their natural range-it's just not the same thing. However, Reginald Mungomery (the man in charge of their introduction) said one year after their introduction:
"This introduction into Queensland was made only after a careful analysis of the pros and cons, and, according to the behaviour of the toad up to present, there appears to be no reason for the assumption that we have made an error in our judgement."
He was paying attention-he weighed the pros and cons and tried to put forethought into his decision with good intentions. He didn't simply do it because he thought it would be a fun idea, but look how that ended up regardless. Even a year after their introduction, the massive damage they eventually caused hadn't been observed. Like I said, show me a single example where humans tampering with an ecosystem has been beneficial when it wasn't cleaning up the mess caused by previous tampering-I honestly do not know of a single case.
These disasters aren't often caused with malicious intent, but by those who don't understand the consequences of their actions. Unless you're very familiar with corn snake ecology in wild (population densities, home range sizes, carrying capacity, regional variations in natural history), you simply can not even make an educated guess how playing with the natural order will or will not affect the future.
Finally, I've spoken my mind and backed up my claims (at least in my own mind)-I won't keep repeating my stance on this issue for the sake of making my disagreement obvious. If anyone specifically addresses me further on any part of this issue, I'll try to continue to keep up with the thread though.
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