Introduction Section 1: Setting the scene: groundwater as ecosystems 1. Hydrodynamics and geomorphology of groundwater environments 2. Classifying groundwater ecosystems 3. Physical and biogeochemical processes of hyporheic exchange in alluvial rivers 4. Ecological and evolutionary jargon in subterranean biology

Section 2: Drivers and patterns of groundwater biodiversity 5. Groundwater biodiversity and constraints to biological distribution 6. Patterns and determinants of richness and composition of the groundwater fauna 7. Phylogenies reveal speciation dynamics: case studies from groundwater 8. Dispersal and geographic range size in groundwater

Section 3: Roles of organisms in groundwater 9. Microbial diversity and processes in groundwater 10. Groundwater food webs 11. Role of invertebrates in ecosystem processes and services

Section 4: Principles of evolution in groundwater 12. Voices from the underground: animal models for the study of trait evolution during groundwater colonization and adaptation 13. Ecological and evolutionary perspectives on groundwater colonization by the amphibian Proteus anguinus 14. The Asellus aquaticus species complex: an invertebrate model in subterranean evolution 15. Developmental and genetic basis of troglomorphic traits in the teleost fish Astyanax mexicanus 16. Ecological and evolutionary perspectives on groundwater colonization by the amphipod crustacean Gammarus minus 17. Evolutionary genomics and transcriptomics in groundwater animals

Section 5: Biological traits in groundwater 18. Dissolving morphological and behavioral traits of groundwater animals into a functional phenotype 19. Life histories in groundwater organisms 20. Physiological tolerance and ecotoxicological constrains of groundwater fauna

Section 6: Section 6: Biodiversity and ecosystem management in groundwater 21. Global groundwater in the Anthropocene 22. Assessing groundwater ecosystem health, status and services 23. Recent concepts and approaches for conserving groundwater biodiversity 24. Existing framework for the conservation of groundwater biodiversity and ecosystem services