Stress marks or overheating?

[David42]

So my little guys about 7 inches, he basks in a 100w hear bulb and temps are around 100-105 when he basks. I notice that when he basks his underside stress marks show and his body seems to darken underneath. I pick him up for a few seconds and his underside goes back to his normal white coloring. Is this a sign of overheating? He's been eating fine and everything seems to be in check for the two weeks I've had him.

 

[bumblebee]

No, he's probably not overheating. Beardies will sometimes get darker when they're basking so they can soak up more heat.