Dictyostelium primarily inhabits soil or dung and "feed" on bacteria. Its spores have thick walls made of cellulose & protein. It is most often known only from laboratory culture in which it develops profusely under proper conditions.
After several divisions of the spore stage, the spores will give rise to amoebae (See Frames 1, 2). When the food supply is exhausted, amoebae will begin to secrete acarsin, a hormone-like substance which attracts other amoebae causing them to stream toward a center of aggregation (See Frames 3,4). After several such amoebae have aggregated, a pseudoplasmodium (slug) is formed (See Frame 5). The slug behaves as a unit and responds as an entity to external conditions (See Frames 6,7,8). (Frames from a video clip. Courtesy of R.H. Woodworth Science Films.)
Life cycle of Dictyostelium.
Return to Menu Page, Subkingdom: Myxobionta