Overharvesting in human patch foraging reflects rational structure learning and adaptive planning

Abstract

Patch foraging presents a sequential decision-making problem widely studied across organisms—stay with a current option or leave it in search of a better alternative? Behavioral ecology has identified an optimal strategy for these decisions, but, across species, foragers systematically deviate from it, staying too long with an option or “overharvesting” relative to this optimum. Despite the ubiquity of this behavior, the mechanism underlying it remains unclear and an object of extensive investigation. Here, we address this gap by approaching foraging as both a decision-making and learning problem. Specifically, we propose a model in which foragers 1) rationally infer the structure of their environment and 2) use their uncertainty over the inferred structure representation to adaptively discount future rewards. We find that overharvesting can emerge from this rational statistical inference and uncertainty adaptation process. In a patch-leaving task, we show that human participants adapt their foraging to the richness and dynamics of the environment in ways consistent with our model. These findings suggest that definitions of optimal foraging could be extended by considering how foragers reduce and adapt to uncertainty over representations of their environment.

Attention deficits linked with proclivity to explore while foraging

“…ADHD-like cognitive phenotypes confer advantages or disadvantages depending on the environment. Foragers with ADHD-like traits may fare poorly in environments with multiple, learnable depletion rates (like the task used in [79]), by leaving patches before gathering enough information to learn the different patch types. In environments in which exhausted patches are renewed, primates are known to track renewal rates, such as the availability of fruit [81][82][83].…”

“…In addition, our task required participants to gather points—an abstract resource that stands in contrast to basic alimentary or other resources like calories. Nonetheless, animals and humans show similar patterns of behaviour that accord with foraging theory, whether foraging for resources in the real world or foraging for food pellets or points on a computer in the laboratory [22,50,55,79].…”

Sex differences in patch-leaving foraging decisions in rats

“…Perhaps the most general explanation—and one not exclusive of various other causes—is that rats were optimizing more than food earnings. In most scenarios foragers must consider many other factors while searching for food, including predation risk (Choi & Kim, 2010; Ydenberg & Dill, 1986), potential competitive or affiliative interactions with conspecifics (Li et al, 2012; Nagy et al, 2020; Whishaw, 1988; Whishaw & Tomie, 1988), energy expenditures (Hart et al, 2017), and opportunities for learning about aspects of their surroundings (Harhen & Bornstein, 2023; Wang & Hayden, 2021). Foraging strategies that balance these and other factors might depart from the predictions of rate maximization but nevertheless perform well in real-world scenarios.…”

“…The marginal value theorem (MVT) provides a means of computing the optimal patch residence time, which occurs when the rate of return from the current patch falls to the average rate of return over the environment as a whole (Charnov, 1976;Kolling & Akam, 2017;Stephens & Krebs, 1986). Previous studies have shown that the qualitative predictions of the MVT hold over a range of species, including humans (Constantino & Daw, 2015;Hall-McMaster et al, 2021;Harhen & Bornstein, 2023;Kolling et al, 2012), nonhuman primates (Barack et al, 2017;Blanchard & Hayden, 2015;Hayden et al, 2011;Turrin et al, 2017), and rodents (Kane et al, 2017(Kane et al, , 2019(Kane et al, , 2022Killeen et al, 1981;López-Yépez et al, 2021).…”

Ignoring the role of reiterative processing and worldview transformation leads to exaggeration of the role of curiosity in creativity

“…By contrast, preferring familiarity can manifest as a form of perseverative information seeking that was associated with deprivation curiosity (Lydon-Staley, , a drive to reduce uncertainty and acquire missing information (Kashdan et al, 2018;. This preference for familiarity has been seen as prevalent in people with greater depressed mood and anxiety (Zhou et al, 2023), and may be an important heuristic strategy to reduce uncertainty for better reliability of future-oriented decisions (Harhen & Bornstein, 2023;Jiang, Kulesza, Singh, & Lewis, 2015). However, in large environments, such local heuristics are impoverished, particularly when higher-order associations are needed for planning.…”