Overview
E-Z1724 is a major downstream branch of E-Z1725 and plays a crucial role in the paternal genetic landscape of West Africa. Its formation near the middle Holocene reflects a period marked by intensifying agriculture, early metallurgical development and the solidification of sedentary communities in the forest–savanna ecotone. The lineage demonstrates a pattern of demographic growth that aligns closely with the expansion of complex societies across the Nigeria–Cameroon border region. This expansion predates the full Bantu dispersal, but E-Z1724 contributed significantly to populations that later formed the demographic foundation for some Central African expansions.
Geographic distribution
E-Z1724 is especially common in Nigeria, Cameroon, Benin and Togo, and occurs at moderate frequencies across Ghana and Ivory Coast. Several subclades show strong affinities with specific ethno-linguistic communities, such as Igbo, Yoruba, Tiv and Edo populations. The lineage spreads into Central Africa primarily through secondary migrations, with presence noted in Gabon, the Republic of Congo and parts of the western Congo Basin. In diaspora populations, E-Z1724 appears in African-American and Afro-Caribbean communities, reflecting West African origins. Overall, its distribution maps closely onto areas linked to early Holocene West African population growth.
Ancient DNA
- Due to DNA preservation limitations in tropical climates, no ancient individuals have been conclusively assigned to E-Z1724, although archaeological sites associated with early sedentary agricultural communities are consistent with its estimated timeline.
- Population modelling indicates that E-Z1724 began diversifying in situ among proto–Niger–Congo groups before the major demographic events associated with the spread of ironworking technologies.
- Several internal sub-branches of E-Z1724 show rapid expansions around 2,500–3,000 years ago, matching the archaeological appearance of iron smelting and increased social complexity in West Africa’s forest–savanna belt.
Phylogeny & subclades
E-Z1724 forms a structurally complex subtree with multiple radiating branches. Its phylogenetic signature includes both moderately deep splits and more recent star-like patterns typical of rapid population growth. The internal diversity of this lineage strongly suggests that it served as an important demographic reservoir for various proto–Niger–Congo populations. Many downstream clades exhibit strong regional clustering, indicating episodes of local founder effects and the establishment of socially cohesive communities that preserved paternal lineages across centuries.
- E-Z1724* (rare basal forms)
- Several region-specific subclades concentrated in Nigeria and Cameroon
- Micro-branches associated with forest–savanna transition populations
- Lineages that later diffused into Central African populations
Notes & context
E-Z1724 is a critical lineage for reconstructing the demographic history of West Africa prior to the large-scale Bantu-associated migrations. Its geographic concentration and phylogenetic depth provide clues about the formation of proto–Niger–Congo linguistic communities and regional settlement patterns. Because its expansions precede and partially overlap with technological shifts in ironworking, E-Z1724 represents one of the lineages most likely to have been present during the formation of early hierarchical societies in the region.
References & external links