Almost 700 years ago, Jacob van Maerlant, a Dutch poet, envisioned a fish all set for life on land: It had sprouted arms to hoist itself ashore. Now, three genetic studies make his fantasy look remarkably prescient. Together, the studies suggest that in terms of genes, the aquatic precursors of four-limbed land animals, or tetrapods, were as well-prepared as the Dutch fantasy fish. They were pre-equipped with genes that could be turned to making limbs, efficient air-breathing lungs, and nervous systems tuned to the challenges of life on land.