"It's done in miniature, not to scale. There's no practical purpose to it. Humans just like building too much to let the opportunity to practice go." The Doctor takes off his coat, the owl scooting on his shoulder fussily to let him, and sets it on the sand. He grabs a bit of driftwood--had it always been there?-- and props the coat up into a little shaded tent, hands the owl carefully into the shade, where she blinks gratefully. Is it still thoughtful if one is doing it for oneself? Essentially? He rolls up his sleeves, surveying the damp sand appraisingly. Better than carbon sand. Definitely.