THE VARIED ROLES OF SNAILS - National Universities Commission

competitively loosely packed. With this form of
distribution, the relative abundance follows the distribution
of resources, with each species occupying its fundamental
niche. In real life, within species rich communities, the
average niche width and niche overlap declines.
The snails are mostly hermaphroditic in nature, this allows
for self fertilization and parthenogenesis, Aphallic species
often occur from African species. Snails also survive in the
environment because of the nature of their shells.
5. IMPORTANT ROLES OF SNAILS IN HUMAN
AFFAIRS
(a) EFFECTS OF SNAILS ON THE ECOSYSTEM:
(h) Feeding: All snails are from one trophic levelprimary
consumers that play important roles in
the functioning of the ecosystems. Quantitative
studies have shown that some activities of the
snails are imperative for the ecosystem dynamics
to operate smoothly (Mason, 1970). The food
choices of snails are influenced by the qualitative
composition of the foods, the qualitative
availability and the nutritional needs of the snails
(Callow, 1971). There is a positive correlation
between food availability and its proportion in
the diet (Okafor, 1990). Diet itself has been
found to vary seasonally and is shown to be
specific to age (Baur, 1992). Snails feed on an
assortment of plant and animal species including
algae, bacteria, and fungi. They feed on whole
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