Reproductive and Physiological Ecology of Climbing and TerrestrialPolybotrya(Dryopteridaceae) at the La Selva Biological Station, Costa Rica

Abstract

Premise of research. Recent studies have suggested that the evolution of holoepiphytism in certain ferns may have proceeded through a hemiepiphytic intermediary. Defining hemiepiphytism in ferns is complicated by the presence of separate, free-living gametophyte and sporophyte stages. Currently, we lack detailed field observations into fern species that have historically been referred to as hemiepiphytes, especially as to whether the gametophytes establish themselves on mineral soil, rotting logs, or the bases of tree trunks. In addition, nothing is known of the physiological shifts that can occur as an individual fern moves from a terrestrial habit to a climbing habit. The goal of this work is to describe the developmental ecology of species that have been termed hemiepiphytes in Polybotrya and examine the ecophysiological changes between terrestrial and climbing individuals.Methodology. The research was carried out at the La Selva Biological Station in Costa Rica, where the developmental ecology was stu...