Sponges of the New Caledonian lagoon - IRD

It was originally assumed that species from the highly diverse tropical reef communities
would demonstrate the highest incidence of biological activity in extracted metabolites
as "chemical warfare" and competition for space was deemed to be most
severe for tropical encrusting invertebrates. Early works produced data which
supported these ideas as high numbers of active compounds were discovered from
tropical species. In fact these results reflected the intensity of work within the tropics
as an equally high incidence of bioactive species has now been reported from
temperate and polar regions of the world. In situ and laboratory experiments
designed to test these chemical ecological hypotheses still remain to be done.
The increased awareness of the potential of marine biological resources, most of
which remain as yet undiscovered, has highlighted the need for nations to become
aware of biological diversity and the importance of conservation of these
resources. Given the present success in finding novel chemicals with potentially
valuable biological activities, there is now intense effort to collect representative
specimens from as many different parts of the world as possible and from as many
different phyla and habitats. This has focused global attention on biodiversity and
the need to ensure that the loss of marine habitats and the species within those
habitats, is halted. AS with the search on land in rainforests for plants and other
organisms which may yield compounds for pharmaceutical applications, so it is
with marine environments. It now appears likely that many species do not have the
wide distributions preViously assumed to be characteristic of marine organisms
which have potentially long larval life cycle stages. In fact the opposite is the case
and most progeny of marine invertebrates and vertebrates alike, settle near
parents. These factors together with the increasing impact that pollution and nonsustainable
fishing techniques are having on tropical reefs have caused many environmental
agencies and researchers to signal a need for habitat protection in an
effort to conserve present biodiversity. As the immediate supply of bioactive compounds
for assay and development is likely to be obtained directly from natural
sources, there is a clear need to gather information about the distribution and abundance
of organisms at the species level to provide accurate systematic information
and to permit sustainable development.
AS mentioned above, many sponge natural products are complex making artificial
synthesis impossible or uneconomic. Although harvesting from the wild can sometimes
supply extracts in sufficient quantity for testing drugs, often the rarity of host
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Sponge
chemistry
and chemical
ecology