Are orchid life histories really irregular? The case of Epipactis albensis

摘要

Empirical data on many species of terrestrial orchids suggest that their between-year flowering pattern is extremely irregular and unpredictable due to costs associated with sexual reproduction and/or herbivory. In a more mathematical context, the irregular behaviour of orchids may be explained by difference equations describing deterministic growth of the vegetative dry weight and deterministic relationships between vegetative and reproductive dry weight. In this paper long-term data on the terrestrial orchid Epipactis albensis are used to test this explanation of the irregular flowering patterns of orchids.