15 research outputs found
Despotism and Risk of Infanticide Influence Grizzly Bear Den-Site Selection
Given documented social dominance and intraspecific predation in bear populations, the ideal despotic distribution model and sex hypothesis of sexual segregation predict adult female grizzly bears (Ursus arctos) will avoid areas occupied by adult males to reduce risk of infanticide. Under ideal despotic distribution, juveniles should similarly avoid adult males to reduce predation risk. Den-site selection and use is an important component of grizzly bear ecology and may be influenced by multiple factors, including risk from conspecifics. To test the role of predation risk and the sex hypothesis of sexual segregation, we compared adult female (n = 142), adult male (n = 36), and juvenile (n = 35) den locations in Denali National Park and Preserve, Alaska, USA. We measured elevation, aspect, slope, and dominant land cover for each den site, and used maximum entropy modeling to determine which variables best predicted den sites. We identified the global model as the best-fitting model for adult female (area under curve (AUC) = 0.926) and elevation as the best predictive variable for adult male (AUC = 0.880) den sites. The model containing land cover and elevation best-predicted juvenile (AUC = 0.841) den sites. Adult females spatially segregated from adult males, with dens characterized by higher elevations ( = 1,412 m, SE = 52) and steeper slopes ( = 21.9°, SE = 1.1) than adult male (elevation: = 1,209 m, SE = 76; slope: = 15.6°, SE = 1.9) den sites. Juveniles used a broad range of landscape attributes but did not avoid adult male denning areas. Observed spatial segregation by adult females supports the sex hypothesis of sexual segregation and we suggest is a mechanism to reduce risk of infanticide. Den site selection of adult males is likely related to distribution of food resources during spring
A Fuzzy-Trace Theory of Risk and Time Preferences in Decision Making: Integrating Cognition and Motivation
We provide an overview of fuzzy-trace theory (FTT) and its implications for risk and time preferences, drawing on evidence from behavioral economics, psychology, and neuroscience. FTT’s central construct is mental representation, specifically verbatim (literal surface form) and gist (bottom-line meaning) representations. The differences between these types of representation determine risk and time preferences, in combination with social values as well as developmental and individual differences. In particular, sensitivity to rewards and inhibitory control vary across the life span and across people, but impulsivity and risk taking can be modified by applying principles of FTT. We discuss the origins of FTT in prospect theory and distinguish risk preference, impulsivity versus intuition, temporal discounting (i.e., delay discounting), and delay of gratification, as well as FTT’s approach compared to standard dual-process models of judgment and decision making. As we discuss, there are parallels in FTT’s explanations of people’s willingness to tolerate risk as well as their willingness to wait for future rewards. FTT predicts theoretically crucial effects, such as increasing cognitive biases from childhood to adulthood, greater “rational” analysis among adolescents compared to adults, elimination of gain–loss biases through truncation of zero parts of gambles in risky choice framing, and hidden-zero effects in temporal discounting. We conclude that FTT yields qualitatively different interpretations of risk preference and time preference compared to other theories and that it offers new approaches to understanding and improving problem behaviors.https://digitalcommons.law.uw.edu/faculty-chapters/1053/thumbnail.jp