Habitat influences psychoactive toad secretions
…human intervention further altered the habitat of the Amazon-Cerrado toads. One could hypothesize that this disturbance could not only affect the habitat, and thus the available food, but it may also put stress on the toads… This stress could conceivably cause them to produce different combinations and amounts of compounds in their secretions by way of currently unknown adaptative mechanisms.
The researchers noted there was another difference between the two regional groups of toads that may have influenced the results. They explained, “…the collection site in the south of the Brazilian Amazon is an area of fully recovered vegetation and with very little human intervention, the collection site of the Amazon-Cerrado region has suffered several anthropic actions.”