Fig. 3: European and North American Holocene pollen diversity trends by biome.
From: Floristic diversity and its relationships with human land use varied regionally during the Holocene
GAMs fit to North American (solid lines) and European (dashed lines) Holocene pollen turnover (Bray–Curtis), richness and evenness data. Heterogeneity panels (Bray–Curtis; final column) are not fitted GAMs but distributions of data (given the reduced heterogeneity sample size arising from the 500 year binning; Methods). Holocene pollen diversity data are shown for each biome that is represented by at least 20 pollen records. The 1,000 resamples (modelled first by GAMs, except in the final column) are then summarized by median (thick lines) and interquartile ranges (shaded intervals). Rows are ordered approximately by latitude. North America (NA) tundra n = 1,130, Europe (EU) tundra n = 1,416 (a–d), NA boreal forests/taiga n = 2,048, EU boreal forests/taiga n = 2,018 (e–h), NA temperate conifer forests n = 4,242, EU temperate conifer forests n = 5,469 (i–l), NA temperate broadleaf and mixed forests n = 6,645, EU temperate broadleaf and mixed forests n = 26,235 (m–p), NA temperate grasslands, savannas and shrublands n = 1,691 (q–t), EU Mediterranean forests, woodland and scrub n = 3,750 (u–x).
