What do you mean by “niche”? Modern ecological theories are not coherent on rhetoric about the niche concept

Abstract

Ecologists have long had a “love-hate” relationship with the niche concept. Sometimes referred to as a term best left undefined, the niche concept nonetheless spans ecology. Deeply rooted in the Darwinian struggle for survival, “niche” has been a core, although slippery, idea in ecology since its origins. What ecologists mean by niche has changed semantically over time. In this paper, we review the history of the term, focusing on its uses and the disagreements that have arisen over it within ecology. Because classic niche concepts are not exclusive and share some similarities, we disentangle them into key theoretical components to create a heuristic classification scheme for niche concepts. We, therefore, analyze coherence on rhetoric within the ecological literature, by classifying how ecologists use niche concepts in their writing, aiming at clarifying communication on what is being studied. To assess if modern ecological theories are coherent in their usage of the niche concept, we surveyed a sample of three research areas: ecological niche modeling, coexistence between species and meta-communities. We found that research agendas are segregated when it comes to rhetoric about niches. Ecologists have long tried to achieve a truly unifying biodiversity theory, or at least a universal definition of niche. We, however, move in the opposite direction and suggest that the niche concept should be dismembered into its key components, highlighting which elements of the concept are being addressed and analyzed. Explicitly stating to which niche concept a study is referring may enhance communication among researchers from different backgrounds and perhaps alleviate this century-old dilemma.