The mutualistic interactions among species have received relatively little
attention in the field of conservation biology. It is especially in insular
ecosystems where it has been found that this type of interactions, particu
larly plant-animal interactions, can be very important for the maintenance
of biodiversity. Islands, with relatively high values of biodiversity, are
especially vulnerable to habitat modifications of any kind, and the loss of
a species can cause a dramatic reduction -or even the extinction- of other
species which depend on the former. In this paper I present some examples
of islands where plant-animal mutualisms an presumably important for the pl
ant community structure and for biodiversity in general. The current major
threats to animal mutualists (pollinators and seed dispersers, in particula
r) are enumerated as well as the factors that need to be considered when pr
edicting the extinction risk of a plant devoid of these mutualists. Finally
, some documented cases of plant-animal mutualism disruption and its conseq
uences are given. Conservation programs are certainly incomplete if they do
not incorporate the study of both evolutionary and ecological mutualistic
interactions among species.