Are igs able to tell when they have had enough UVB basking for the day? Akin to how they know to thermoregulate.
I was reading on one site yesterday about their vision and it stated that they eyes see shorter light wave lengths than ours -- that is into what we call the ultraviolet spectrum. On the same lines as another post that started into igs "eating colours" it went into how many flowers are very vivid in the UV rays and we don't see it but insects do.
I don't beleive that they have anyway of deciding how much UVB they have recieved. Its more along the idea that they bask in the sun to warm up and when they are warm enough they move away. The fact that they get the uvb they need is just an adaption to this behavior. If you put a uvb bulb in the cooler area of your enclosure and a heat lamp on the warm end the ig will seek out the heat regardless of whether it is providing uv. That is why we as owners have to arrange things so that the basking area is also the area exposed to the UV.
Mark we(me and razzi) were just talking about that last night...this is just a guess but it would make sense about there eyesight, like how some insects and other animals can see when a plant or fruit is almost ripe...where we cant.. Makes sense that if you get to it first there is not as much competition from others that can't tell it's ripe...