Table 1.

Different approaches to studying meaning in primates’ gestural and vocal communication.

	Gestures	Vocalizations
Who is studied?	Signaler (and recipient)	Recipient
Is intentionality considered?	Yes (production)	No
How is meaning studied?	Intended meaning	Extracted meaning
Which signals are studied?	Context-unspecific	Context-specific
What is the relationship between signal and referent?	No one-to-one referential meaning between pointing gestures and their varying referents	One-to-one referential meaning between functionally referential signals and their referents
Which species are studied?	Apes	Monkeys
Which methods are used?	Observations	Playback experiments
Where are studies conducted?	Captivity	Natural habitats