7. Application to basic landscape genetics
Finally, to verify that eDNA can address basic landscape genetics
questions, we examined whether two patterns previously shown in the
targeted system (Nakajima et al. 2021) were also detected by analysis
using eDNA. These patterns were: (i) genetic differentiation is
significantly correlated with waterway geographic distance
(isolation-by-distance) and (ii) genetic differentiation is not
correlated with differences in summer water temperature between
populations. From the 19 populations except Pop 20 and Pop 21 where
water temperature data are unavailable and 13 populations in the
upstream dataset (assuming local scale studies), correlations ofD PS with waterway geographic distance and water
temperature differences were calculated by Mantel tests with 9999
permutations.