At last warmer weather and rain has enlivened the Daintree Rainforest, ending a long, cold winter. With below average rainfall, the rich and vibrant presence of fungi has been lessened, but today the Yellow (Many-headed) Slime Mould (Physarum polycephalum) appeared on a log in a shady section of the rainforest.
Not unlike bureaucracies, the slime mould has many heads that meet to agree on a course of action. Slime molds are important heterotrophs (cannot synthesize their own food) in the decomposition of organic matter in temperate and tropical forests. The ‘Many-headed slime’ inhabits shady, cool, moist areas, such as decaying leaves and logs. It is sensitive to light; but in particular, light can repel the slime-mould and also be a factor in triggering spore growth. The plasmodium (above) consists of networks of protoplasmic veins with multiple nuclei. This is the active, streaming form of slime mould that searches for and surrounds its food and secretes enzymes to digest it.
Typically yellow, P. polycephalum eats fungal spores, bacteria and other microbes. If the slime mould runs short of food, or conditions are not favourable, it starts to reproduce and, bureaucratically creates more heads!
Physarum polycephalum has been shown to exhibit intelligent characteristics similar to those seen in single-celled creatures and insects with social structures or castes, such as ants, bees and wasps. The mould can also create networks to navigate between strategically laid down food sources in a manner that compares favourably with rail lines and road networks between townships and cities, in terms of efficiency and cost effectiveness. In Japan, scientists replicated the city of Tokyo and 36 surrounding townships using oat flakes on agar agar. The introduced slime mould formed a network that closely resembled the railroads constructed by humans!