Ecological Epigenetics: Research Fronts, Taxonomic Gaps, and a Five-Year Forecast

Ecological epigenetics investigates the role of molecular modifications, including DNA methylation, in heritable phenotypic variation in natural populations, often arising in response to environmental conditions. Because such modifications can respond to environmental change within a single generation, the field has direct relevance for understanding adaptation, plasticity, and the persistence of populations under habitat alteration and climate change. However, bibliometric attention has focused predominantly on the biomedical side of epigenetics, particularly cancer and clinical applications, while the structure and trajectory of the ecological literature have not been mapped. In the present study, 962 records published between 2000 and April 2026 were identified in the Web of Science Core Collection after two-stage filtering and analysed with the bibliometrix R package, complemented by time-series forecasting and segmented-regression analysis. The literature expanded at a compound annual rate of 12.16%, with output decelerating after a structural break in approximately 2014. Plants dominated the corpus at 52.70%, whereas mammals, fish, birds, reptiles, amphibians, and the invertebrate groups remained under-represented relative to their ecological and conservation importance. Two-thirds of records could not be linked to a specific ecosystem, reflecting the field’s strong laboratory orientation. Keyword co-occurrence networks organised the field around three macro-themes: a molecular-mechanism axis, an ecological-context axis, and a conservation-and-management axis. Multiple growth models converged on a marked slowdown in publication growth, consistent with approaching saturation rather than continued exponential expansion, projecting a near-flat output of roughly 52–54 records per year through 2030 (95% bounds widening to 14–89) and a model-averaged carrying capacity near 1,835 cumulative records. The taxonomic imbalance documented here reveals a structural gap in the field’s coverage of biodiversity, with implications for conservation genetics and the design of future ecological-epigenetics research.