Spatial and temporal TLR3 variation across islands
The earliest available samples from the source population, Cousin (120 birds caught in 1993 and 1994), were used to provide a proxy estimate of the initial TLR3 diversity on Aride and Cousine (which were established in 1988 and 1990, i.e.. before sampling took place). Samples from 56 of the 58 birds translocated to Denis, and all 59 birds translocated to Frégate were used to determine initial TLR3diversity on these islands. The most recent population samples were of 58 individuals caught in 2018 on Frégate, 158 individuals caught in 2015 on Denis, 54 individuals caught in 2012 and 2016 on Aride, 72 individuals caught in 2019 on Cousine, and 196 individuals caught in 2018 on Cousin.
Genepop 4.2 (Rousset, 2008) was used to test if the different island populations conformed to HWE (as above). We tested for temporal and spatial divergence in TLR3 frequencies among populations using genic differentiation tests (Raymond & Rousset, 1995) in Genepop 4.2 (Rousset, 2008). Fisher’s exact test and the Markov chain algorithm parameters were as above. First, we tested for differentiation between the initial (translocated or 1993–94 samples) and most recent samples from each population. Second, we tested for differentiation among populations using the most recent samples.