The Relation between Flowers, Seeds and Fruits

Abstract

Since the rise of Pteridosperms, the seed has become the normal organ of generative, recombinative dispersal. Why then the fruit? In the chapter on evolution we shall see in detail that the fruit is in principle an interpolation, the continuation of a new organ of the flower, the ovary. This persisted after flowering and, after a phase where it was only a nuisance, it usually became an auxiliary organ of dispersal which supplanted the seed as such. Morphologically the difference between the two seems clear, the one arises from an ovule and the other from an ovary. Difficulties arise when we consider whether all ovaries are comparable or not, and whether perhaps some ovaries are homologous with seeds. As long as this does not involve ecology, we might leave these questions to morphologists, but this attitude becomes untenable when we realize that pure morphology is an abstraction, that morphology is perhaps the crystallized or fossilized ecology of former eras.