A team from the Doñana Biological Station – CSIC has reviewed a exhaustive standardized historical survey (Relaciones Topográficas de Felipe II) with the goal of knowing which species inhabited the Iberian Peninsula at that time.

In the 16th century, bears and wolves coexisted with the Iberian lynx, wild asses still existed in Spain and eels were in every river. Data is collected in an open database for new research.