The drone landed in a tree, extended its legs, and began to slowly creep along the trunk. And, I realized with a start, it was really a tree. It was brown—well, brownish— tall, hard, and had branches and leafy things. It looked like a pretty clear case of convergent evolution. It was, in fact, the kind of tree that I loved to climb when I was young. Wide, horizontal branchings produced many convenient places to sit. Thick leaf canopies kept the sun off. And the sheer size of the trees was awe-inspiring. I wanted to hug one.