Risk sensitivity in starlings: Variability in food amount and food delay

Starlings' preferences for constant versus variable food sources were studied in the laboratory. The constant alternative gave a fixed amount of food after a fixed delay. The variable alternative offered either a varying amount of food after a fixed delay (treatment A) or a fixed amount of food...

Descripción completa

Guardado en:
Detalles Bibliográficos
Publicado: 1991
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10452249_v2_n4_p301_Reboreda
http://hdl.handle.net/20.500.12110/paper_10452249_v2_n4_p301_Reboreda
Aporte de:
id paper:paper_10452249_v2_n4_p301_Reboreda
record_format dspace
spelling paper:paper_10452249_v2_n4_p301_Reboreda2023-06-08T16:01:09Z Risk sensitivity in starlings: Variability in food amount and food delay feeding memory risk sensitivity starling Sturnus vulgaris Starlings' preferences for constant versus variable food sources were studied in the laboratory. The constant alternative gave a fixed amount of food after a fixed delay. The variable alternative offered either a varying amount of food after a fixed delay (treatment A) or a fixed amount of food after a variable delay (treatment B). In both treatments the ratio of amount of food over trial length (the sum of intertrial interval plus delay and handling times) of the constant alternative equaled the average of the two ratios of the variable alternative. The variable ratios were 30% higher and 30% smaller than the fixed ratio. In free-choice trials (both options available in each trial), the subjects were risk-averse or indifferent in treatment A and indifferent or riskprone in treatment B. In no-choice trials (only one source available per trial), the latency to respond was longer in the variable than in the constant source in treatment A and the opposite in treatment B. The greater preference for variability in time than for variability in reward amount is not consistent with either maximizing the ratio of expected energy over expected time or the expected ratio of energy over time for individual trials. There was a negative correlation between individual intake rate and degree of risk proneness for both kinds of variability. We present a model of choice based on an information-processing theory for temporal memory that accounts for the different effects of variability in delay and in amount but cannot explain the effects of intake rate. [Behav Ecol 1991;2:301-308] © 1991 International Society for Behavioral Ecology. 1991 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10452249_v2_n4_p301_Reboreda http://hdl.handle.net/20.500.12110/paper_10452249_v2_n4_p301_Reboreda
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic feeding
memory
risk sensitivity
starling
Sturnus vulgaris
spellingShingle feeding
memory
risk sensitivity
starling
Sturnus vulgaris
Risk sensitivity in starlings: Variability in food amount and food delay
topic_facet feeding
memory
risk sensitivity
starling
Sturnus vulgaris
description Starlings' preferences for constant versus variable food sources were studied in the laboratory. The constant alternative gave a fixed amount of food after a fixed delay. The variable alternative offered either a varying amount of food after a fixed delay (treatment A) or a fixed amount of food after a variable delay (treatment B). In both treatments the ratio of amount of food over trial length (the sum of intertrial interval plus delay and handling times) of the constant alternative equaled the average of the two ratios of the variable alternative. The variable ratios were 30% higher and 30% smaller than the fixed ratio. In free-choice trials (both options available in each trial), the subjects were risk-averse or indifferent in treatment A and indifferent or riskprone in treatment B. In no-choice trials (only one source available per trial), the latency to respond was longer in the variable than in the constant source in treatment A and the opposite in treatment B. The greater preference for variability in time than for variability in reward amount is not consistent with either maximizing the ratio of expected energy over expected time or the expected ratio of energy over time for individual trials. There was a negative correlation between individual intake rate and degree of risk proneness for both kinds of variability. We present a model of choice based on an information-processing theory for temporal memory that accounts for the different effects of variability in delay and in amount but cannot explain the effects of intake rate. [Behav Ecol 1991;2:301-308] © 1991 International Society for Behavioral Ecology.
title Risk sensitivity in starlings: Variability in food amount and food delay
title_short Risk sensitivity in starlings: Variability in food amount and food delay
title_full Risk sensitivity in starlings: Variability in food amount and food delay
title_fullStr Risk sensitivity in starlings: Variability in food amount and food delay
title_full_unstemmed Risk sensitivity in starlings: Variability in food amount and food delay
title_sort risk sensitivity in starlings: variability in food amount and food delay
publishDate 1991
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10452249_v2_n4_p301_Reboreda
http://hdl.handle.net/20.500.12110/paper_10452249_v2_n4_p301_Reboreda
_version_ 1768543239948730368