Slime mould
Dictyosteliida: unicellular slime moulds or dictyostelids. The Dictyosteliida, cellular slime moulds, are distantly related to the plasmodial slime moulds and have a very different lifestyle. Their amoebae do not form huge groups, and stay individual. They live in similar habitats and feed on microorganisms. When food runs out and they are ready to form sporangia, they do something radically different. They release signal molecules into their environment, by which they find each other and create swarms. These amoeba then join up into a tiny multicellular slug-like coordinated creature, which crawls to an open lit place and grows into a fruiting body. Some of the amoebae become spores to begin the next generation, but some of the amoebae sacrifice themselves to become a dead stalk, lifting the spores up into the air.