Another sign how intelligence and memory play together:
I have a transport box for Taco, just in case he has to go to the vet or similar.
Its like a small tote, clear plastic. To keep him used to it, each time I weigh him, I put him into the box.
The first time I put him in - he was a bit older than half a year old, and he scratched me up badly. He also hit me with his tail, too. I nevertheless put him in. I took the weight, then took Taco out and back into his enclosure.
First, I expected a similar bad reaction when I come with the box the next time. But no: I could put him in, he didn't fight.
My interpretation: The first time, he associated being put into a small - small compared to his enclosure - box with being given away. I got him from the pet store in a cardboard box (picked him up here in town), and he was not bred there but comes from a breeder about 1500 km away (yes, those dragons are quite unusual here, so the long distance) and was shipped from there to the pet store.
So he was twice in boxes and that meant: being brought away, environment changes, stress.
The second time I put him into the transport box, however, he knew that won't happen.
There was never any problem with the transport box after.
Picking one can be a difficult question, but I believe one always gets some lovely coloration - being it that deep orange of this one, with a weird pattern in another one, with an unusual dark coloration in the next one....
For my Taco, when I went to the reptile store the second time (the first time I was there to ask if they have bearded dragons at all, because reptiles are quite unusual pets here, and after they told me they have regularly some, I ordered the enclosure and all the equipment with help of this forum

) I just wanted to ask whether they either have some right now or if I can reserve already one of the next they will get.
They had exactly one beardie left, already 3 months old (normally they sell them from really baby-size on). I reserved him and picked him up a week later. What I got was a chocolate-brown (with a bit grey) beardie with a pattern that reminded me a bit of a carpet. I didn't mind, but I just wondered as I automatically thought when I get a bearded dragon, this animal will have a light, sand-tone coloration. Over time, his coloration got much lighter and brighter. That's him, approx. 4 months old vs. over a year old.