From niche theory to demographic realities: the demographic niche concept for understanding range‐wide population dynamics

Journal article

The ecological niche concept is fundamental to understanding species distributions but often overlooks the demographic processes shaping said distributions. Conversely, demographic theory has traditionally neglected how vital rates vary and covary across environments, limiting our understanding of population dynamics across species' ranges. Over 50 years ago, Maguire proposed conceptualising the ecological niche as composed of multiple ‘demographic niches' corresponding to separate vital rates such as survival, development, and reproduction. Although Maguire's perspective failed to gain prominence – constrained by the demography theory, data, and tools at the time – it provides a foundation we now expand upon. Here, we formalise the demographic niche concept (DNC), integrating Maguire's perspective with recent advances in niche theory and demography. We review the theoretical foundations of demographic niches, outline the tenets of the DNC, and define demographic niches (using phenology and ontogeny as guiding axes) and their boundaries (in terms of vital rate variation along environmental gradients). We then introduce a framework for visualising the arrangement of demographic niches in environmental and geographic space, clarifying how overlap or divergence shapes persistence across time and space, extinction debts under global change, or reveal intervention opportunities. We also propose the unimodal response hypothesis, predicting that vital rates peak at optimal conditions and decline toward margins, with deviations revealing additional ecological processes such as demographic compensation, density dependence, or niche truncation. Throughout this review, we discuss methods for modelling and integrating demographic niches and their relevance for addressing global challenges such as climate change. While data requirements remain non‐trivial, this barrier is rapidly shrinking as demographic datasets grow, process‐based models become more accessible, and remote sensing capabilities improve. By advancing the conceptual and methodological foundations of the DNC, this review establishes a basis for future empirical research and applications, offering new directions for ecological theory and conservation amidst a changing world.

Authors: Pang, SEH; Fenollosa, E; Merow, C; Guisan, A; Svenning, J

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Ecography
• Article number: e07774
• Publication date: 2026-04-29
• Acceptance date: 2026-03-13
• DOI: 10.1002/ecog.07774
• EISSN: 1600-0587
• ISSN: 0906-7590
• Language: English
• Keywords: life history; climate change; demographic distribution; niche modelling; vital rates; environmental gradients