Towards strategy concepts in flower ecology as exemplified by the fig-wasp symbiosis

For a discussion of its various aspects1, it is convenient to recognize flower ecology as passing through three phases. Initially, in a descriptive phase, special instances of reproductive behaviour and their mechanisms are described. Then follows a phase of reflection, allowing of some inductive generalization e.g., recognition of pollination syndromes. In a third phase, by comparing the phenomena placed in a taxonomic arrangement (as a repository of their phylogeny), one can pose explanatory hypotheses in the form of strategies for optimally deploying available resources and adaptive mechanisms. For example, the first two phases can be taken together in the story of fig wasps pollinating the flowers of figs (fig. 1, taken from Wiebes 1919,fig. 1). Fig. 2 illustrates the mechanism in that it visualizes how the fore feet manipulate the pollen around the pollen pockets in the mesosternum. In one group of fig wasps we find another mode of pollen transport and pollination i.e., by carrying the pollen in a fold of the hypopygium or in intersegmental and pleural invaginations that form in the shrunken body of the wasp following loss of water in the old fig, to regain the swollen form in the young fig. The recent-most addition to our knowledge of fig-pollination was made by Okamoto & Tashiro (1981). As a generalization one would suppose two groups of wasps and figs, characterized by either of the two modes of pollination. This is defied, however, by the current classification of fig wasps, as well as by a claim of a third mode found with Tetrapus-wasps i.e., ingestion of pollen when in the old fig, followed by regurgitation in the young one. Yet, Tetrapus appears to have what looks like incipient pollen pockets on the mesosternum (fig. 3} and could be considered a first stage of the first mode.