Extended Data Fig. 2: Spatial composition of β-diversity across grid cells by voucher and observation records.
From: Mass production of unvouchered records fails to represent global biodiversity patterns
Maps of dissimilarity between record types for: (a, b) Plants (n = 240,377 species), (c, d) Butterflies (n = 9809 species), (e, f) Amphibians (n = 4862 species), (g, h) Birds (n = 9380 species), (i, j) Reptiles (n = 7259 species), and (k, l) Mammals (n = 4508 species). Dissimilarity was assessed by generating pairwise distance matrices of Simpson’s β-diversity between all pairs of grid cells within major biogeographically defined areas recognized by the Biodiversity Information Standards (also known as the Taxonomic Databases Working Group (TDWG)). Values of β vary between 0 (species composition is identical between grid cells) and 1 (high dissimilarity, no shared taxa). Both voucher and observation records of most taxonomic groups showed high dissimilarity in less frequently sampled regions of South America, Africa, and Southeast Asia, and decline in frequently sampled Europe and North America.
