Population genetic summary statistics and its relationship to patch size
A contrasting pattern in genetic diversity metrics in small and large patches was observed between the two species (Figures S6 & S7; Table S4). Radula flaccida in small patches (1-ha and 10-ha), presented a similar proportion of variant sites, polymorphic sites, and allelic richness when compared to large patches (100-ha and continuous forest) (p-value = >0.05. Table S6). Private alleles (R2 = 0.20, p-value = >0.05) and nucleotide diversity (R2 = 0.15, p-value = >0.05) decreased towards larger patches when the complete dataset was considered. For Cololejeunea surinamensis , populations in small patches (1-ha and 10-ha) present lower genetic diversity in all five calculated metrics than populations in large patches (100-ha and continuous forests) (Table S6). This difference was more evident and statistically significant for polymorphic sites (R2 = 0.52 - 0.67, p-value = <0.05) and nucleotide diversity (R2 = 0.50 - 0.58, p-value = 0.01) with both datasets (Table S6). The observed genotype diversity (MLG) showed similar patterns. An overall similar genotype diversity was observed between small and large patches for R. flaccida populations (R2 = 0.08,p-value = >0.05). A lower genotype diversity in small patches compared to populations in large patches of C. surinamensis. This pattern was only significant with the reduced dataset (R2 = 0.49, p-value = <0.05).
The richness index used, Shannon-Weiner Diversity index (H), Stoddard and Taylor’s Index (G), and Simpson’s index (lambda) suggest thatR. flaccida population genetic diversity did not differ between small and large patches (p-value = >0.05; Figure S7). Populations in 1-ha fragments show a slightly lower richness compared to populations in 10-, 100-ha, and continuous forests when the complete dataset was considered (Table S5). On the contrary, for the species C. surinamensis, the three richness indexes were reduced towards smaller patches when the reduced dataset was considered (Figure S7). The Shannon-Weiner Diversity index (H) (R2= 0.43, p-value = <0.05) and Stoddard and Taylor’s Index (G) (R2 = 0.49, p-value = 0.01) were statistically significant, while the reduced diversity in small patches observed with the Simpson’s index (lambda) was not significant (R2 = 0.30, p-value = >0.05) (Table S6).