The evolution of decision-making strategies

Why have humans evolved irrational decision-making biases, even when they are skilled at weighing costs and benefits accurately in a variety of other contexts? For example, people devalue options as they are pushed into the future, and generally avoid risk. Although many components of human economic behaviour are typical of our species (i.e., only humans use money as a medium of exchange), other primates face similar choices in their natural habitats, making tradeoffs between the energetic or temporal costs and the possible benefits. I compare human and non-human primates’ decision-making strategies in similar contexts to shed light upon which aspects of economic decision-making are unique to humans, versus more widely shared. This research is done in collaboration with the Unit of Cognitive Primatology in Rome and the Department of Psychology of the Sapienza University of Rome.

Recent publications:

De Petrillo, F. & Rosati, A.G. (In press). Decision-making in animals: rational choices and adaptive strategies. To appear in: Cambridge Handbook of Animal Cognition (A. Kaufman, J. Call. & J. Kaufman, eds.) Cambridge: Cambridge University Press.

De Petrillo F. & Rosati A.G. (2021). Variation in primate decision-making under uncertainty and the roots of human economic behaviour. Philosophical Transactions of the Royal Society B, 376, 20190671

Evolutionary variation in judgment and decision-making

Which factors are responsible for interspecific differences in cognitive skills? My research seeks to elucidate how different species acquire and process information from the physical and the social world and whether variation in cognitive abilities, including decision strategies, relates to differences in life history, ecology and social structure. I address these questions by studying the psychology of different primate populations, including captive brown capuchin monkeys at the Unit of Cognitive Primatology in Rome, two free-ranging population of macaques, rhesus and Barbary macaques, living respectively at Cayo Santiago Field Station, Puerto Rico and at Trentham Monkey Forest, and different species of lemurs – Coquerel’s sifaka (Propithecus coquereli), ruffed lemurs (Varecia sp.), ringtailed lemurs (Lemur catta), and aye-aye (Daubentonia madascarensis) at the Duke Lemur Center. This line of research is conducted in collaboration with the Cognitive Evolution Group at the Department of Psychology, University of Michigan.

Recent publications:

De Petrillo F. & Rosati A.G. (2020). Logical inferences from visual and auditory information in ruffed lemurs and sifakas. Animal Behaviour, 164, 193-204.

De Petrillo F. & Rosati A.G. (2019). Rhesus macaques use probabilities to predict future events. Evolution and Human Behavior, 40, 5, 436-446

De Petrillo F. & Rosati A.G. (2019). Ecological rationality: convergent decision-making in apes and capuchins. Invited paper, Society for the Quantitative Analysis of Behavior Special Issue in Behavioural Processes, 164, 201-213

The development of decision strategies during the lifespan

How do decision strategies change over human development? This research line seeks to address the origins and development of inter-individual variability in decision-making, such as differences between genders and across ages, by understanding which cognitive abilities and emotional correlates underpin an individual’s decision strategies at different stages of their lives. In collaboration with the Department of Psychology at the Sapienza University of Rome, I study decision strategies, including intertemporal choice and risk decisions, in preschool children of 3-6 years old.

Recent publications:

In prep Paoletti M., Bellagamba F., Gagliardi R…, De Petrillo F, Addessi E. Decision-making
under risk and experienced regret in preschoolers and school-aged children.

The evolution of money

The use of money is evolutionarily unique to humans, so why is our species so motivated to obtain money? My research investigates whether the ability to categorize money can be traced back to non-human primates, by analysing the exchange behaviour of brown tufted capuchin monkeys. This research is done in collaboration with the Unit of Cognitive Primatology of Rome and the Institut Jean Nicod in Paris.

Recent publications:

Addessi E., Quintiero E., Gastaldi S., De Petrillo F., Bourgeois-Gironde S. (2021). Quality-quantity trade-off in the acquisition of token preference by capuchin monkeys (Sapajus spp.). Philosophical Transactions of the Royal Society B, 376, 20190662

De Petrillo F., Caroli M., Gori E., Micucci A., Gastaldi S., Bourgeois-Gironde S., & Addessi E. (2019). Evolutionary origins of money categorization and exchange: an experimental investigation in tufted capuchin monkeys (Sapajus spp.). Animal cognition, 1-18