Why do chams turn bright at night?

[Jupiter]

Does anyone know? That seems like a good way to end up as midnight snack

 

[Solid Snake]

http://http://en.wikipedia.org/wiki/Chromatophore#Pigment_translocation

It has been demonstrated that the process can be under hormonal, neuronal control or both.

 

[Jupiter]

Oooo thats a great link, thanks! I wasn't asking how though, I was asking why. Whats the benefit to being bright at night?

 

[KingJulian]

Maybe the bright colors tell predators to stay away. Not too sure, I've wondered the same thing.

 

[stalincat]

According to David Attenborough they sleep at the tips of branches, so it's very few predators which could actually get them.

 

[patrickfraser]

They are their brightest when most relaxed. I wonder if they get brighter in a good dream or possibly darken or stress color for a bad one?

 

[moogle73]

According to David Attenborough they sleep at the tips of branches, so it's very few predators which could actually get them.

Well at least with mine, they do follow this as well when sleeping. They always seem to be at the end or near the end of a branch when sleeping.

But I have a feeling their color at night is due to "its more of it doesn't really matter" situation then any specific reasoning, and its just their ultra relaxed coloring (when they are really bright like that).

Reason I say this is unless its a full moon and REALLY BRIGHT out at night, its hard to make out the chameleons anyway (at least for me). When I walk by their enclosure at night in a dark room (and I'm talking DARK like nearly pitch black dead of night dark), they could be bright florescent orange or neon pink, but its so dark in the room and cages its nearly impossible to make them out if you didn't already know where they were.

Obviously they stand right out once you put on a small light, or flashlight, but relying solely on very minor refracted light at night i find it a lot of times hard if not impossible to make them out. So I have a feeling most nights in the wild would be the same for them and predators with the exception of full moon nights etc.

 

[Solid Snake]

Oooo thats a great link, thanks! I wasn't asking how though, I was asking why. Whats the benefit to being bright at night?

To start, we must clarify, and ask not what is the benefit, but why has this trait remained, when it would seem to make them stand out, in a compromising position?

I then ask, what is it that would see them at night, and think they looked tasty?

If anything, I would assume it to be birds. Or maybe some sort of nocturnal, carnivorous, mammal.

I imagine there are many brightly colored leaves, flowers, and fruits and such in the jungle, that also glow and stand out against tree trunks, and darker leaves. So I dont think a bird flying around would necessarily notice a bright panther on the edge of a branch.

The nocturnal, carnivorous, mammal would need to make its way to the chameleon, thus, it would need to climb along the branch the animal is on.

As Stalincat has stated, they tend to sleep at the very edge of a branch. This gives them advanced warning of any supposed nocturnal, carnivorous, mammalian attack, as the branch would shake and sway as the nocturnal, carnivorous, mammal made its way towards making its way to making the sleeping chameleon lunch.

Also, these supposed predators may not necessarily see the same spectrum of light as you or I, so that may also be a factor.

Furthermore, I assume that the amount of UV light hitting the skin has a lot to do with it. The tissue may just be responding to the change in lighting, possibly coupled with neuro-chemical and hormone changes that take place during sleep.