Application of Molecular Genetics to Earthworm Ecology: Current Research and Promising Future Directions

In earthworm ecology, the use of molecular tools has been restricted to certain fields such as ecotoxicology. In this chapter, we highlight two key issues of earthworm ecology that would greatly benefit from molecular information: dispersal behaviour and reproductive strategies. Elucidating patterns of dispersal is fundamental in guiding our understanding of earthworms’ distribution in both time and space. Field methods traditionally employed for measuring dispersal are difficult to use in species hidden in the soil, such as earthworms. Alternatively, genetic tools allow assessing dispersal from the detailed analysis of the genetic structure within and among populations. Besides, a good understanding of the mating strategy is essential to interpret population genetic patterns, particularly in species that present a great diversity of reproductive modes such as earthworms. After a short presentation of available genetic markers for earthworm genetics and a summary of the recent advances in molecular taxonomy of earthworms, current research in earthworm dispersal and mating behaviour are presented and the interest of using molecular markers for genetic inference is discussed.