Liquid droplets are a research platform used in ALife to study the emergence of complex life-like behaviors from fairly simple combinations of chemicals. Droplets are created by putting a drop of one liquid (such as oil) into a different liquid that it cannot mix with (such as water). Additional chemicals are then added to droplet and/or the liquid around it. By choosing the right chemicals, droplets can be created that form complex patterns, solve problems such as mazes, or even interact with each other. For a review of droplet research and a discussion of why droplets can be thought of as liquid robots, see the following paper, which won the ISAL Outstanding Publication of 2017 award:
For more information, see the following talk by Silvia Holler at the 2021 ISAL Summer School:
Droplet experiments lend themselves to videos! For a collection of videos of droplet experiments, check out the following playlist by Jitka Cejkova: