An operating cost of learning in Drosophila melanogaster

被引:99
作者
Mery, F [1 ]
Kawecki, TJ [1 ]
机构
[1] Univ Fribourg, Dept Biol, Div Ecol & Evolut, CH-1700 Fribourg, Switzerland
关键词
D O I
10.1016/j.anbehav.2003.12.005
中图分类号
B84 [心理学]; C [社会科学总论]; Q98 [人类学];
学科分类号
03 ; 0303 ; 030303 ; 04 ; 0402 ;
摘要
Although the fitness benefits of learning are well understood, we know little about its costs; yet both are essential to understand the evolution of animal learning. We tested the hypothesis that learning has an operating cost, such that an animal repeatedly forced to use its learning ability would show a reduction in some fitness component(s), relative to an animal of the same genotype that does not have to learn. Five 'High-learning' lines of Drosophila melanogaster, which had been selected for improved learning ability, 0 were exposed to 12 consecutive 48-h cycles of alternating conditioning treatment under mild nutritional stress. Their learning score first increased, reaching a maximum around day 12 (i.e. the sixth conditioning cycle), and then progressively declined. These changes were not due to ageing, as they were not observed in flies from the same lines maintained under standard conditions. From around day 12, the productivity (egg-laying rate) of the flies in the conditioning treatment became progressively reduced, relative to flies from the same lines not exposed to conditioning, but otherwise kept under the same food-limited conditions. This reduction in productivity was not observed when these treatments were applied to five 'Low-learning' lines, which had not been exposed to selection, and which show no detectable response to conditioning under our experimental conditions. Furthermore, exposure to repeated cycles of conditioning revealed an apparent trade-off between the learning score and productivity among the 'High-learning' lines. These results indicate an operating cost of learning, paid only by genotypes that show learning, rather than general effects of stress caused by the conditioning regime. Potential proximate explanations include (1) the impairment of oviposition decisions caused by the accumulation of memory interference and (2) energy costs of collecting, processing and storing information. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:589 / 598
页数:10
相关论文
共 32 条
[1]   Neural limitations in phytophagous insects: Implications for diet breadth and evolution of host affiliation [J].
Bernays, EA .
ANNUAL REVIEW OF ENTOMOLOGY, 2001, 46 :703-727
[2]   A larger hippocampus is associated with longer-lasting spatial memory [J].
Biegler, R ;
McGregor, A ;
Krebs, JR ;
Healy, SD .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2001, 98 (12) :6941-6944
[3]   COVARIATIONS BETWEEN HIPPOCAMPAL MOSSY FIBERS AND WORKING AND REFERENCE MEMORY IN SPATIAL AND NONSPATIAL RADIAL MAZE TASKS IN MICE [J].
CRUSIO, WE ;
SCHWEGLER, H ;
BRUST, I .
EUROPEAN JOURNAL OF NEUROSCIENCE, 1993, 5 (10) :1413-1420
[4]   Costs of memory: Ideas and predictions [J].
Dukas, R .
JOURNAL OF THEORETICAL BIOLOGY, 1999, 197 (01) :41-50
[5]  
Dukas Reuven, 1998, P129
[6]   Adaptive learning of host preference in a herbivorous arthropod [J].
Egas, M ;
Sabelis, MW .
ECOLOGY LETTERS, 2001, 4 (03) :190-195
[7]   ECOLOGY AND ENERGETICS OF ENCEPHALIZATION IN HOMINID EVOLUTION [J].
FOLEY, RA ;
LEE, PC .
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES, 1991, 334 (1270) :223-232
[8]  
FRESQUET N, 1993, Q J EXP PSYCHOL-B, V46, P399
[9]  
Geervliet JBF, 1998, ENTOMOL EXP APPL, V86, P241, DOI 10.1023/A:1003186706517
[10]   How many flower types can bumble bees work at the same time? [J].
Gegear, RJ ;
Laverty, TM .
CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE, 1998, 76 (07) :1358-1365