Setup of a study using motion tracking to investigate continuous properties of evolving manual signals. Panel a: Seed gestures for a fixed set of meanings are learned by next generations in an iterative learning experiment. Panel b: Using motion tracking, we derive automatic kinematic measures of entropy, temporal variability and intermittency over time and over generations.
My dear friend Ruben Owiafe was one of the most colourful Siwu teachers I had. His explanation of what it means to provide folk definitions is insightful in terms of both its content and form. As he explained, they enable you to see one thing in terms of another: “If you see this here” (points to his right), “you see how it is here” (points to his left). Figures and diagrams in academic publications serve the same kind of purpose. They provide us with different ways of seeing, and help us understand by analogy.
On the ground is a plate of metal on which two small amounts of gunpowder have been laid to dry in the sun; besides it stands the speaker, explaining why one needs to be careful when igniting the gunpowder to test its quality: it may flare up “SHÛ, SHÛ”, a vocal depiction that is produced in precise synchrony with the two hands moving symmetrically in a quick upward motion. (The right hand holds an object.)