"Soil invertebrates consist of a great variety of body plans and life-forms, since about every phylum of the animal kingdom has at least some representatives in the soil, while some are almost exclusively soil-living. All soil invertebrates descend from originally marine ancestors that have undergone many independent terrestrializations. In addition, several lineages that became fully terrestrial in their later evolution have adopted a secondary soil-living life-style. Upon all these life-forms, the soil environment has imposed similar conditions relating to space, humidity, temperature gradients and microbial communities. As a consequence we see many similar adaptations, both in reproductive biology and life-history, but also in physiology and molecular responses. The soil invertebrate community is an example par excellence of convergent and parallel evolution"--