An integrated framework to improve the concept of resource specialisation

Area of Science:

• Ecology
• Evolutionary Biology
• Quantitative Biology

Background:

• Resource specialisation is key in ecology but lacks a unified definition.
• Current methods often rely on simple species counts, leading to overestimations.
• Advances in ecophylogenetics and null models offer new analytical approaches.

Purpose of the Study:

• To propose a novel, robust measure of ecological specialisation.
• To integrate resource affinities and consumer-resource interactions into specialisation metrics.
• To disambiguate the concept of specialisation for broader application.

Main Methods:

• Developed the distance-based specialisation index (DSI).
• Incorporated resource relatedness (phylogenetic or otherwise) and null model analysis.
• Applied the DSI to a dataset of herbivorous insects and their host plants.

Main Results:

• The DSI accurately measures specialisation by considering resource relatedness and abundance.
• Specialists exhibit significantly clustered resource use; generalists show over-dispersed use.
• The DSI is more effective than traditional methods, especially with limited sampling.

Conclusions:

• The DSI provides an explicit, versatile measure of ecological specialisation.
• This framework links specialisation to ecological and evolutionary processes.
• Enables more rigorous empirical and theoretical studies of specialisation.