No,
slime moulds are not fungi. They are members of the
Kingdom Protozoa. They used to be included among the fungi
because people found their dry fruiting structures in the
woods when they were out collecting fungi.
In fact,
the most characteristic structure of a slime mould is a
plasmodium -- a giant amoeba with thousands of nuclei in
a single mass of protoplasm. This plasmodium moves around
slowly in decaying organic matter or the soil, eating -
swallowing up or ingesting -- bacteria and other tiny particles
of organic matter.
No true
fungus 'eats' in this way. All fungi have to absorb their
food.
When
the giant amoeba has accumulated enough food reserves, or
when the weather gets cold or dry, the plasmodium will undergo
an amazing change, turning from a slimy, slowly undulating
mass into a series of small, dry fruiting bodies which contain
powdery spores.
After
they have been dispersed, each of these spores will germinate
and release a tiny amoeba which, if it successfully finds
and mates with another amoeba, can then begin to feed and
develop into a new plasmodium.
Slime
moulds used to be called Myxomycetes, but this name implied
that they were a kind of fungus, so they are now called
Myxostelida, which is one of many Phyla in the Kingdom Protozoa.
[Remember that we now recognize seven
Kingdoms.
There are two prokaryotic Kingdoms: Archaebacteria and Eubacteria.
There are five eukaryotic Kingdoms: Plantae, Animalia, Eumycota
(Fungi), Chromista (Stramenopila), and Protozoa.]
To see
some pictures of Myxostelida, go to Chapter
2a.
For
a more detailed account, refer to Chapter 2 of the book
and CD-ROM.
