In the 1990s critiques on early biodiversity–ecosystem function (B-EF) research pushed the field towards direct and random biodiversity manipulations.

This evolution allowed the establishment of causal relationships between ecosystem functioning and biodiversity, a main research gap at that time.

A main research gap today is to predict and mechanistically understand shifts of ecosystem functioning following real-world biodiversity shifts caused by different types of environmental change.

Data from direct and random biodiversity manipulations do not predict the functioning of ecosystems that experience biodiversity shifts as these shifts are often nonrandom and combine with a series of other effects such as changes in per capita functioning and density.

Environmental change drivers are useful as they offer experimental control over: (i) the relative magnitude of the different facets of biodiversity change; and (ii) food web composition. These two features facilitate inference of the mechanisms connecting environmental change with ecosystem functioning.