A drone drops a small wooden projectile with three spiral tails and a seed mounted on the tip. It gently lands on the bare ground and sits there, exposed to the elements, until it rains. Then, the moisture penetrates the wood fibres, and the spiral tails start twisting, slowly pushing the seed into the ground, where it will germinate.
The design of this incredible depth-seeking seed carrier, recently published in Nature, was inspired by the self-burying mechanism of a few plant species, such as those of the genus Erodium.
