Conclusion
We found strong evidence that
selection – acting through both survival and (to a lesser degree)
reproduction, was associated with TLR3 locus variation in the
contemporary Cousin population. This suggests that an unknown pathogen
is present in the Seychelles warbler population, driving evolution at
this TLR3 locus. It is possible that this current positive
selection may be part of a much longer-term pattern of balancing
selection, but only further monitoring will be able to determine this.