Evolution of Natural History Collection autonomy in the Global South: the case of Neotropical freshwater fishes

Neotropical freshwater fish type specimens have historically been concentrated in Global North institutions, which led scientific activity in the 19th and 20th centuries. Despite recent advances in taxonomic activity in Neotropical countries, the dispersion of type specimens still hinders biodiversity research in the Neotropics. This study examines the spatiotemporal (1758–2025) distribution of 8252 Neotropical freshwater fish type specimens, analysing retention trends, geopolitical influences, and legislative impacts. Our results revealed that 61% of types are housed in Global North collections. Historical dominance by European and US institutions shifted after 1950 and especially in the last few decades, with Brazil and Colombia retaining almost all of their type specimens collected in the post-2000 period, while Venezuela lost retention capability in the same period. Legislative efforts boosted retention in Brazil and Colombia but had little effect elsewhere. Natural History Collections remain threatened by underfunding and institutional instability, which can lead to the disappearance of unique type specimens. We advocate for the ethical deposition of type specimens in origin countries, fostering access to Neotropical type specimens for researchers from the original countries, and infrastructure investments in Global South collections to decentralize biodiversity knowledge, build capacity, and strengthen taxonomic research in the Neotropics.