Figure 13.14 The probability of plant populations going extinct. Researchers surveyed 359 plant populations in Germany in 1986 and then again in 1996. They then placed the populations into six size categories and averaged extinction rates across the eight species. They found that populations with the lowest number of individuals experienced the highest probability of extinction over a 10-year period.

Data from D. Matthies et al., Population size and the risk of local extinction: Empirical evidence from rare plants, Oikos 105 (2004): 481–488.