There are many hypotheses describing the interactions involved in biological invasions, but it is largely unknown whether they are backed up by empirical evidence. Invasion Biology fills that gap by developing a tool for assessing research hypotheses and applying it to a number of invasion hypotheses, using the hierarchy-of-hypotheses (HoH) approach, and mapping the connections between theory and evidence. In Part 1, an overview chapter of invasion biology is followed by an introduction to the HoH approach and short chapters by science theorists and philosophers that comment on the approach. Part 2 outlines the invasion hypotheses and their interrelationships. These include biotic resistance and island susceptibility hypotheses, disturbance hypothesis, invasional meltdown hypothesis, enemy release hypothesis, evolution of increased competitive ability and shifting defence hypotheses, tens rule, phenotypic plasticity hypothesis, Darwin's naturalisation & limiting similarity hypotheses and the propagule pressure hypothesis. Part 3 suggests future directions for invasion research.
Part I: Introduction to invasion biology and the hierarchy-of-hypotheses approach
Chapter 1: Invasion biology: searching for predictions and prevention, and avoiding lost causes
Chapter 2: The hierarchy-of-hypotheses approach
Chapter 3: Hierarchy of hypotheses or hierarchy of predictions? Clarifying key concepts in ecological research
Chapter 4: Mapping theoretical and evidential landscapes in ecological science: Levins' virtue trade-off and the hierarchy-of-hypotheses approach
Chapter 5: A hierarchy of hypotheses or a network of models
Chapter 6: The hierarchy-of-hypotheses approach updated - a toolbox for structuring and analysing theory, research and evidence
Part II: Hypothesis network and 12 focal hypotheses
Chapter 7: A network of invasion hypotheses
Chapter 8: Biotic resistance and island susceptibility hypotheses
Chapter 9: Disturbance hypothesis
Chapter 10: Invasional meltdown hypothesis
Chapter 11: Enemy release hypothesis
Chapter 12: Evolution of increased competitive ability and shifting defence hypotheses
Chapter 13: Tens rule
Chapter 14: Phenotypic plasticity hypothesis
Chapter 15: Darwin's naturalisation and limiting similarity hypotheses
Chapter 16: Propagule pressure hypothesis
Part III: Synthesis and outlook
Chapter 17: Synthesis
Chapter 18: Conclusions and outlook