A network of fish ponds supported a permanent human settlement in the seasonal drylands of Bolivia more than one thousand years ago, according to a new study published May 15, 2019 in the open-access journal PLOS ONE by Gabriela Prestes-Carneiro of Federal University of Western Para, Brazil, and colleagues. The study is the first to document the full range of fish species likely kept in these constructed ponds, and provides new insights into how humans modified the savannah environment to cope with the months-long droughts that characterize this region of the Amazon Basin.