*5.2. Generating Layer*

The generating layer represents the effect factors related to a species' life history and behavior. Due to biodiversity, community structures and biological parts of ecosystems can be considered as the existential state of species at a higher scale, and this layer can then be defined as the generating layer. Variations in biodiversity, community structures or biological parts of ecosystem can result from variations in the generating layer similar to how bodily variations can result from gene variations. The generating layer covers two features: species life history (e.g., the birth, senility, illness, and death of a species) and species behavior (e.g., competitiveness, mutualism, predation, etc.). There is an interaction effect between these two sections. For example, Maynard [22] quantified the links among a competitive network structure, biodiversity, and community functioning, and found that a competitive network can determine the direction of BEF relationships.
