Something that confuses me

[X-Factor]

This thought/problem occurred to me earlier...hit me like a Mack truck. Now, my knowledge of the mechanics of evolution is limited but what I DO know causes me to be rather curious about this.... I'm sure this thread will end up getting moved to debate but I don't see this being a debate. I'm looking for an answer WHY. Wish we had some biologists here... anyway here goes:

If a reptile (python eg) sees poorly in the spectrum that we humans call "sight" and more with heat, or thermal imaging, how did it evolve body colors and patterns for camoflague and to seek out natural camoflague? Heat signatures don't blend in to colder terrain - certainly not well enough that a pit viper or carpet python couldn't detect them - and colored caudal lures (Boas for example) would not appear to work without a knowledge of the prey's prey stemming from an elevated visual accuity. Under thermal observation camoflague would appear to be ineffective, and visual observation either must be MUCH more acute than previously asserted, or else continues the problem.

If you see only using military thermal goggles you only see varying degrees of heat (snakes MUCH more so), not color, therefore the use of color to hunt/hude would not evolve. If your visual spectrum more mimics humans (as opposed to naked mole rats) color for predation and procreation WOULD necessarily evolve, and quite spectacularly as we see. Combine the two and you have a super predator.

I must conclude that snakes (all snakes), especially those with heat pits, are much more visually acute than we think, and to process that much data must be more "intelligent" or discriminating than we think. Everything that snakes are and are capable of is the result of long eons of evolution, so there had to be a reason and ability to continue. If there is little or no visual acuity to determine color for survival reasons, then HOW does it continue? A few conjectures:

-Snakes can smell their own species for breeding purposes, though in cannabilistic species this makes it less opportunistic and more intentional. The other problem with this theory is that with just smell you end up with a hit or miss genetic pool that never really progresses, and that has not happened.
-Snakes can see MUCH better than we think, those with pits have evolved them and are more effective. Perhaps they evolved them to compensate? This doesn't really address the issue at hand.
-Heat signatures. They could detect their own species for breeding using heat signatures. This falls down on two points. 1) The non heat pit species obviously, and 2) the heat pit species would have to be more sensitive to this than we have previously thought.

I know someone is saying to themselves that I'm mixing up the two basic types of snake and lumping pits with those without, but I'm not. Snakes with heat pits would necessarily have to see better to help identify prey and potential mates, though not AS much as snakes WITHOUT them. I submit that heat pits are more evolved but do not detract from excellent visual acuity. Those without them are less evolved but necessarily also have excellent visual range.

Sorry I'm long winded. I'm done. Thoughts? Comments?

[HastetheDay]

Very interesting comments - I had not thought of it that way before.

Now if only we can get someone in here who can show us some scientific evidence either backing up or denying your "theory."

I would start googling if it wasn't almost time for work. =/ Interested to see if this turns anything up, though!

[X-Factor]

Yeah I just want an answer....don't care if I'm proven wrong.

Google is NOT my friend so starting there would have been a waste of my time.

[KyleZ]

To me, it's pretty simple. Evolution of particular traits or visual cues really has nothing to do with sight, at least not on the snake's part. It's natural selection. If a certain set of appearance traits is more successful (in the case of snakes, in evasion or prey luring) then these traits will continue to be passed along over time, having nothing to do with what a snake can see or not.

In the cases of heat pits/scales, I imagine snakes don't use thermal senses when finding mates, as a snake is generally the same temperature as it's environment, making a thermal profile very poor. I figure they use their thermal senses to find warm-blooded prey, defend themselves from warm-blooded animals, and to locate optimal thermal conditions for themselves. Snakes, unlike birds, for example, are not known to select mates by colors/patterns, (or any visual cues, for that matter) and they are not sexually dimorphic by color. I believe they select mates almost exclusively by scent, which is influenced at certain times of the year by hormones and pheromones.

It's well known that some snakes have greater visual senses than others, by studying the complexity of their eye structures and behaviors, but I believe precise detection of movement is the main function and evolutionary thrust of the snake's eye.

[X-Factor]

Originally Posted by KyleZ

To me, it's pretty simple. Evolution of particular traits or visual cues really has nothing to do with sight, at least not on the snake's part. It's natural selection. If a certain set of appearance traits is more successful (in the case of snakes, in evasion or prey luring) then these traits will continue to be passed along over time, having nothing to do with what a snake can see or not.

In the cases of heat pits/scales, I imagine snakes don't use thermal senses when finding mates, as a snake is generally the same temperature as it's environment, making a thermal profile very poor. I figure they use their thermal senses to find warm-blooded prey, defend themselves from warm-blooded animals, and to locate optimal thermal conditions for themselves. Snakes, unlike birds, for example, are not known to select mates by colors/patterns, (or any visual cues, for that matter) and they are not sexually dimorphic by color. I believe they select mates almost exclusively by scent, which is influenced at certain times of the year by hormones and pheromones.

It's well known that some snakes have greater visual senses than others, by studying the complexity of their eye structures and behaviors, but I believe precise detection of movement is the main function and evolutionary thrust of the snake's eye.

Evolution isn't an invisible "hand" per se, what "works" and continues is a result of success and subsequent breeding of that trait. It works, but not because some invisible force commands it or plays with the genetics. If it didn't work it would have disappeared, that it does suggests that the snake is at least somewhat cognizant of it. If they weren't aware of it then how could they use it? Instinct is possible, but as some point there had to be a connection made between "I'm green" and "that leaf is green" and "I can hide under that leaf." Chance plays no part in it.

[KyleZ]

Originally Posted by X-Factor

Evolution isn't an invisible "hand" per se, what "works" and continues is a result of success and subsequent breeding of that trait. It works, but not because some invisible force commands it or plays with the genetics. If it didn't work it would have disappeared, that it does suggests that the snake is at least somewhat cognizant of it. If they weren't aware of it then how could they use it? Instinct is possible, but as some point there had to be a connection made between "I'm green" and "that leaf is green" and "I can hide under that leaf." Chance plays no part in it.

Are you suggesting that the forces of adaptation through natural selection are a conscious and 'aware' part of a creature's psyche? I guess I'm not following this logic...especially as it pertains to snakes.

The very principle of natural selection (which is the framework of evolution) is that it is the time-proven, unseen force of trial and error, cause and effect over eons of time that determines what passes on, specializes, and functions successfully, as opposed to what does not pass on, and dies out. Take albinos for example...they occur in the wild, but the trait is rarely passed along because it's a naturally unsuccessful one, not because other snakes don't like the way albinos look...The animals rarely, if ever make it to adulthood because they are naturally 'weeded-out.' Obviously, if given the chance and environmental cues, as in captivity, a snake will mate with a counterpart of it's species as long as it's recognizable by scent alone, regardless of how the other snake looks, this is how we end up with morphs.

I believe that snake species are genetically hard-wired in their behaviors, and that some have a natural instinctual predisposition to lay in leaf litter, for example, because this is part of their genetic footprint. I do not believe they are aware of nor 'care' what the leaf litter looks like, just that they are predisposed to burrow themselves down into it. Over eons this has coincided with the natural selection of their color and body shape, and you end up with a naturally specialized animal with a naturally successful genetic blueprint that continues through generations. Same for arboreal species, etc. For example, in captivity, burrowing, ground-dwellers such as Dumeril's boas or Blood pythons will gladly burrow and dig in crumpled newspaper or aspen, even if it is not camoflauging them at all, but they naturally feel they are in their element simply because they are allowed to indulge in their instinctual behavior. Same goes for chondros who function and flourish on white pvc rods, as to them, it seems enough like a branch, even though it's visually far from one...they don't seem to be able to tell the difference, at least not visually...

	Morph A morph is a color or pattern variation that is proven to be genetic. Common morphs include albino, anerythristic, gentically striped, Hypomelanistic, and many others. Morphs also include combinations of simple traits such as "Sunglow" which is Albino and Hypomelanistic. These traits may be recessive traits, co-dominant traits, dominant traits, or created through selective breeding (ie Pastel).

	Arboreal Arboreal is a word meaning "related to or resembling trees". Its meaning comes from the Latin arbor, meaning tree.<br> In biology, an arboreal animal is one which inhabits or spends large amounts of time in trees or bushes.

[X-Factor]

Ok I see your point, but WHY did these things develop, HOW did they come about?

Genetics favor strong dominant traits, and obviously what we are seeing are, for the most part, those genes.

Crap now I'm confused....

[KyleZ]

Originally Posted by X-Factor

Ok I see your point, but WHY did these things develop, HOW did they come about?

Assigning cause and purpose to the workings of the universe is the neverending philosophical conundrum of mankind And that's where strict Darwinism can run into mental roadblocks for some folks (myself included on occasion), but his explanation is as follows:

The theory of evolution states that all adaptations in creatures are due to mutations. Darwin doesn't assign a why to his theory, only a how, which is this system of mutations over time. Some mutations are favorable, and continue to pass on, and modify over generations and generations, eventually becoming a well-defined trait (and sets of traits). Now this isn't saying that one day a snake was born with some crazy mutation such as a perfect heat pit, and 'boom there you have it,' but rather a verrrrrrry long and gradual set of favorable mutations that leads you eventually over many thousands of years to a specialized structure such as a heat pit. It can be very difficult to wrap your mind around a system derived totally of mutations over time, but this is the foundation of the theory.

Philosophy and Darwinism don't always go hand-in-hand, but essentially his why is basically survival, and his how is by changes over time that favor survival in the most effecient and reproductively viable way...

[X-Factor]

Makes more sense.

[John_White]

Snake that are not adequately camouflaged are killed by predators and don't pass along their genes. Snakes that are not seen survive and pass along their genes.

[sixth_sense]

Well put John.

[Ranger]

Another way to think about it is that the ones with bright, obvious colors that didn't blend in got eaten before they could pass on their genes, so the result over many generations is that well hidden critters passed on their genes while poorly hidden ones didn't, so all the ones we know are well hidden.

Why are most humans at least a little afraid of heights (or dangerous animals, etc.)? Because the ones who weren't died before passing on their genes.

Traits that make a creature less well equipped to survive, get ejected from the gene pool over time, because the carriers of those genes don't survive.

[Stargazer]

The obvious answer is the colors evolved as a means of fooling predators, as Ranger says, and not to detect each other. However, some of the camouflage patterns of snakes in their natural habitat is astounding. It's hard to imagine that is only a result of natural selection.

[Special K]

Originally Posted by Stargazer

However, some of the camouflage patterns of snakes in their natural habitat is astounding. It's hard to imagine that is only a result of natural selection.

Mother Nature chooses the best clothes for her children.

[Stargazer]

Thank God it's a woman who chooses the clothes. If men did it, they'd all have the same boring pattern, and the colors wouldn't match. lol

[Special K]

Originally Posted by Stargazer

If men did it, they'd all have the same boring pattern, and the colors wouldn't match. lol

You wonder why you don't ever hear about Father Nature...
He was weeded out by natural selection!

[X-Factor]

Gotta love how a thread derails SO quickly.....Can we bring this back to the land of reality at some point?