Rabbits (Oryctolagus cuniculus) select small seeds when feeding on the fruits of Corema album

Herbivores are hypothesized to consume fruits and seeds while foraging on the vegetative parts of plants. A small seed size is an important condition for this foliage-as-fruit hypothesis to be proved, but has received little attention at the intra-specific level. We measured Corema album seeds ingested by rabbits and those collected from plants and found that rabbits are actively selecting for small seeds. The mechanisms of this selection remain unclear, although my results discard (1) the phenology of consumption, (2) effects of gut passage, and (3) intra-plant heterogeneity of seed sizes as possible mechanisms.