XVI International Botanical Congess
Most studies on the population ecology of bryophytes have been done on common species. However, there are some studies comparing life history strategies in rare and common species. We review the life history strategies (life expectancy, sexual and asexual reproduction, spore number and size, and dispersal) for different types of rare species in connection with pattern and persistency of suitable habitat patches. In particular, we discuss the dynamics on two levels, within and between localities, for different types of rare species. We hypothesize, that most rare species will have restricted dispersal capacities but higher than average life expectancies of local subpopulations. Natural rarity is distinguished from human-induced rarity and species rare for the latter reason are regarded as threatened.