Slime mold cells are microscopic and amoeba like and probably more closely related to protozoa than fungi. They feed mostly on bacteria. Slime mold reproduction is very complex. It starts with a single spore that germinates when conditions are right, releasing cells that have whip-like tails or flagellate, or amoeboid without flagellates depending upon moisture conditions.
These cells may merge with compatible cells to form a zygote which then feeds and grows, and expands into a larger form called a plasmodium. During this process, the nucleus divides many times, but the cells do not divide. The result is a mature plasmodium with thousands of nuclei, but only one giant cell. This cell is bound by cell membrane or enclosed by a slime sheath.
After sufficient feeding the slime mold migrates to a drier location with more light. Here, a remarkable transformation takes place. The slime mold stops feeding and moving, and the plasmodium produces a fruiting body. At certain times, probably when the food source is exhausted, they aggregate to form the visible sporangia. These structures are formed very rapidly, sometimes overnight in resonse to certain signals such as limited food or changes in temperature or moisture. During this stage, the slime mold completes its life cycle by releasing spores from the fruiting body, which are dispersed by wind to new locations. During this phase it is at its most visible. Fruiting bodies are found in many diverse shapes and colours, from cushion-shaped mass or globe-shaped sacs on thin stalks and even plume shaped. Slime molds are often found on rotting logs or decaying stumps. Picture taken 7th May 2007 at Felmersham, Bedfordshire.