Overview
- The Nature Communications paper, published Tuesday, June 23, 2026, shows elastic rope‑coiling theory combined with gravity and the direction of extrusion explains why faeces form either pointy, tapered mounds or constant‑radius spirals.
- The team found downward defecation produces successively smaller coils because fall height drops as the pile grows, which yields the cone shape used by the standard poo emoji.
- Lugworms extrude upward into a different mechanical regime where coil radius stays constant with height, producing the uniform spiral castings long noted by Darwin.
- Researchers validated the theory with measurements from real lugworm samples and lab analogs such as extruded pea dough and pasta, showing stiffness, extrusion rate, and fall height change details but direction dominates the outcome.
- As a public follow‑up the authors plan to design and propose a second poo emoji to the Unicode Consortium, a cultural step that would be separate from the scientific finding and not yet submitted or approved.