Do bearded dragons "know" the UVB bulbs are their suns?

[nuclearkielbasa]

Can they actually sense the rays coming from those bulbs?

My adopted boy lived in a tank with a spot/coil UVB for 3 years; we have him in a tank with a 34" Retpisun t5 mounted inside on the ceiling. On sunny days, he has been nonstop wanting to get out, and when he does he goes right to the sunspots on the floor and pancakes out. (they had him in a hallway with no natural sun before) If my bulb happens to be a dud, is that why he's wanting real sun (even tho he's not getting any rays thru the glass)? Or has he not 'learned' that bulb IS his sun?

I've bought some of those uv-testing cards, just to be safe.

 

[smaugthebeardie3756]

They can actually see ultraviolet light. Their third eye on top of the head senses light and shadow, and they have four color cones in their eyes as opposed to our three. The extra cone allows them to actually see the ultraviolet spectrum. He's probably going for the IR heat he gets from the sun. Penetrates deeper into the muscle than most basking bulbs.

 

[CooperDragon]

He can sense the UVB as mentioned, and will use it when he wants to. That may not be all the time though. It is also common for them to enjoy pancake mode in spots of sunlight coming through a window. That is also beneficial and should be encouraged if he seems to enjoy it.