In the early days of the world, there was naught but dirt, water, mud and grass. Kuwatuwan The Uninspired, creator of the Darien isthmus (construction projects involve a lot of outsourcing) sat and thought. As he thought, he toyed with the mud and dirt, forming it into a small pile. Looking down on what he made, he smiled. Then he sneezed. Having inadvertently breathed life into his creation, he blinked slowly as the toad flopped out of his hand and hopped away. Kuwatuwan looked about to make sure his supervisor wasn’t looking his way. Noticing that she was distracted overseeing Pacific Ring of Fire, he nudged the toad under a large clump of grass and wandered off to work on his next assignment … digging the Himalayan sea.
A while later, the toads were taken to Australia to eat the grey-backed cane and Frenchi beetles. Because introducing animals in Australia always goes well.