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Does a cornsnake's environment affect its coloration

BobM
02-09-2007, 06:49 PM
I was/am watching a crocodile hunter episode in which steve goes to eglin airforce base. During part of the episode he goes to some vietnam-recreation tunnels(built in the last 40+ yrs) to look for bats and finds one of the coolest corns i have ever seen. It has reddish orangish spots down its spine but other than that is almost entirely grey/black. It colors are so striking, at first i thought it was an anerythistic (sp?) snake. I always thought that snakes like that are a biproduct of intensive inbreeding like amerythistic (sp?) This got me to wondering if it was the environment that promoted cornsnakes of such strange coloration, or if cornsnakes of different colorations choose different environments. In other words, is it selective breeding the only influence on a snakes coloration or does it naturally adapt.

Your opinion please...

diamondlil
02-09-2007, 06:55 PM
Maybe selective pressure, plus isolation from other populations is the explanation?
Here's a link to a similar topic

http://emporium.turnpike.net/C/cs/peppered.htm

SkyChimp
02-09-2007, 09:01 PM
In some respect, I think there is a very good chance that environment can effect coloration in the same species. To what extent it effects Corn Snakes I know not. But I've seen this in wild Cottonmouth and Northern Watersnakes that are separated by mere miles but live in completely different types of wetlands.

For instance, I've noticed that Cottonmouths and Northern Watersnakes that lives in wetlands where the principal body of water is high in tanic acid, the coloration tends to be light and the banding very visible. However, the same species living in wetlands where the water is lower in tanic acid the coloration tends to be darker and with the bands not being so prominent.

I'm no herpetologist, but I have seen this enough to believe that the water acidity may be the major influence on the color of the snake. If it can affect these species in this way, I don't know why other environmental factors wouldn't affect other species in different ways.

Also, genetics in local populations probably play a major part, too.

Santa
02-15-2007, 12:26 AM
I would agree that something (either genetics or environment) is responsible for some change in coloration. The local population of corns on the North/East side of the Cape Fear River are not nearly as colorful as those on the opposite side. They have very bright shiny colors for about 5 days after a shed for males & 3 days for females, then it will become dull (similar to a normal corn about to shed) untill the next shed. There is very little color change during the "blue eye" stage.

Corns on the other side of the river keep their coloring untill the shed phase.

I don't know why, but I know it happens.

Shaky
02-23-2007, 09:49 PM
Steve Irwin was known to "plant" certain animals for the "Whoa, look what I stumbled across!" look. Many of the docu-type filmmakers do.
I wouldn't trust that animal to be from that locale, necessarily.
As far as corns in general, their coloration is fairly cryptic in fallen leaves and bark, and as they are primarily nocturnal, the coloration wouldn't negatively affect them when they are on the move. I wouldn't say that their locale has much to do with color.

Jrgh17
02-25-2007, 05:04 PM
Well, the animals environment can affect the population's genetics. A common example (used in bio classes) is the colors of moths before and after the industrial revolution. Before the industrial revolution, the moths were mainly a light tan color, but every once in awhile, you would find a dark moth. After the industrial revolution, the reverse was seen. Many dark moths, with only a few scattered light ones. The reasoning is that before the industrial revolution (when the sky was generally lighter) the light moths blended better with the sky. Since the white moths were more camouflaged, and were preyed on less, they were more likely to survive to reproductive maturity. Thus, the lighter moth passed it's genes on more regularly than the dark moth. After the industrial revolution, the skies were darker. Thus, the dark colored moths were more likely to survive, and reproduce, meaning the population was overall darker.

The same thing could happen in corns (over generations) based on what adapts them best to their environment.