Data from: Historical amphibian declines and extinctions in Brazil linked to chytridiomycosis

The recent increase in emerging fungal diseases is causing unprecedented
threats to biodiversity. The origin of spread of the frog-killing fungus
Batrachochytrium dendrobatidis (Bd) is a matter of continued debate. To
date, the historical amphibian declines in Brazil could not be attributed
to chytridiomycosis; the high diversity of hosts coupled with the presence
of several Bd lineages predating the reported declines raised the
hypothesis that a hypervirulent Bd genotype spread from Brazil to other
continents causing the recent global amphibian crisis. We tested for a
spatio-temporal overlap between Bd and areas of historical amphibian
population declines and extinctions in Brazil. A spatio-temporal
convergence between Bd and declines would support the hypothesis that
Brazilian amphibians were not adapted to Bd prior to the reported
declines, thus weakening the hypothesis that Brazil was the global origin
of Bd emergence. Alternatively, a lack of spatio-temporal association
between Bd and frog declines would indicate an evolution of host
resistance in Brazilian frogs predating Bd's global emergence,
further supporting Brazil as the potential origin of the Bd panzootic.
Here, we Bd-screened over 30 000 museum-preserved tadpoles collected in
Brazil between 1930 and 2015 and overlaid spatio-temporal Bd data with
areas of historical amphibian declines. We detected an increase in the
proportion of Bd-infected tadpoles during the peak of amphibian declines
(1979–1987). We also found that clusters of Bd-positive samples
spatio-temporally overlapped with most records of amphibian declines in
Brazil's Atlantic Forest. Our findings indicate that Brazil is post
epizootic for chytridiomycosis and provide another piece to the puzzle to
explain the origin of Bd globally.