This is the element of the study that is perhaps the most creative.

Brumm’s team needed to answer a specific question: could sucking a whole, unprocessed areca nut — without the slaked lime that modern users add, which intensifies arecoline extraction — actually release enough arecoline to have a physiological effect?

To find out, they soaked intact betel nuts in artificial saliva and then tested the resulting solution against a panel of cloned human receptors expressed in frog egg cells — the standard preparation for testing how compounds interact with human neurochemistry.

The result was clear: yes.