my bearded dragon has a black back normal color is light brown

Question
QUESTION: i just recieved a phone call from my fiance he was saying that our bearded dragon 3 years old possibly older who is normaly a light brown with darker brown design was completly black his whole head not just the beard his front two legs down to just above his back two legs completly black and about 4 inches of the end of his tail i have tried searching for this cant find any information i was talking to somebody and they asked if his legs were yellow at all they were not but all they would tell me is that a beardie with a black back and yellow feet is not good at all that got me nervous so now i want to know what that means also since his feet werent yellow what doeas all black mean i know his beard and a chest can get black but i never heard of his whole body turning black please help me i just got him checked at a vet and they gave him a clean bill of health

ANSWER:   Beardies normally darken when they need to absorb more heat and UVB.  If your UVB source is over 6 months old, get a new one right away, either a linear fluorescent or a mercury vapor bulb.  Check your temperatures.  If these are good, I would say it is an odd change, and if your vet says he's healthy, it could just be him.  I happen to have a solid sable colored beardie about a year old.  Do you have females?  He may be reacting to smelling a female as it is mating season now.  Then there is one other thing to consider, I don't know where you are, but if you are in Australia, or somewhere where another beardie species, Pogona Barbata, are being raised, they have a tendency to be very dark on the whole back.  They also have bullet heads and the inside of the mouth is naturally yellow.

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QUESTION: well im deffinetly not in australia (wish i was) im in pennsylvaina but he did see a picture of a bearded dragon the night before all this started accidently of course it was laying next to his viv dont know whether it was a female or not but there are no other beardies near him and he has lately been showing his beard and bobbin his head at me he seems to calm down when he is getting a bath so im thinking maybe starting to shed but i thought they turned whitish when shedding and also the UVB/UVA in a reptisun 10.0 and it was just changed about a week and a half ago i was also throwing around the idea that the bulb is a dud i did recently make his basking spot closer to his basking bulb he seems to enjoy it but still turns black just not as often and still bobbin and flaring no trouble eating but pooped only once in 3 days and that was yesterday afternoonhe is not on and kind of sand substrate how good is their sense of smell cause the neighbor just got a beardie im not sure its a female though ha that would be kind of weird if that was it

Answer
 What kind of Reptisun?  I hope it's the linear fluorescent, because the compact will cause serious eye injury and should be changed immediately.
 They have an acute sense of smell.  When I got a delivery of an adult female, my male went ballistic when I brought the still sealed box into the house!  So it is possible now that we are opening windows for the warmer weather.  And the neighbor's dragon doesn't have to be female.  Beardies are very territorial and will attack other males, so smelling a new male may produce a similar response.