The radius and ulna of adult frog forearms are always fused into a single structure, as shown in this 3D model of the natal ghost frog, Hadromophryne natalensis.

Well-preserved skeleton of a fossil frog from the Geiseltal Collection. The frog likely died during mating in a swamp environment and broke into two pieces due to currents on the lake bottom.

There's a whole world under the surface and only Ron has any idea about it. And sometimes the two worlds collide, and sometimes they don't. Ron holds them at arm's length from each other. Watch every ...