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Title: Non-human primate token use shows possibilities but also limitations for establishing a form of currency
Non-human primates evaluate choices based on quantitative information and subjective valuation of options. Non-human primates can learn to value tokens as placeholders for primary rewards (such as food). With those tokens established as a potential form of ‘currency’, it is then possible to examine how they respond to opportunities to earn and use tokens in ways such as accumulating tokens or exchanging tokens with each other or with human experimenters to gain primary rewards. Sometimes, individuals make efficient and beneficial choices to obtain tokens and then exchange them at the right moments to gain optimal reward. Sometimes, they even accumulate such rewards through extended delay of gratification, or through other exchange-based interactions. Thus, non-human primates are capable of associating value to arbitrary tokens that may function as currency-like stimuli, but there also are strong limitations on how non-human primates can integrate such tokens into choice situations or use such tokens to fully ‘symbolize’ economic decision-making. These limitations are important to acknowledge when considering the evolutionary emergence of currency use in our species. This article is part of the theme issue ‘Existence and prevalence of economic behaviours among non-human primates’.  more » « less
Award ID(s):
1658867
PAR ID:
10226210
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Philosophical Transactions of the Royal Society B: Biological Sciences
Volume:
376
Issue:
1819
ISSN:
0962-8436
Page Range / eLocation ID:
20190675
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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