Environmental change enhances cognitive abilities in fish.
Flexible or innovative behavior is advantageous, especially when animals are exposed to frequent and unpredictable environmental perturbations. Improved cognitive abilities can help animals to respond quickly and adequately to environmental dynamics, and therefore changing environments may select for higher cognitive abilities. Increased cognitive abilities can be attained, for instance, if environmental change during ontogeny triggers plastic adaptive responses improving the learning capacity of exposed individuals. We tested the learning abilities of fishes in response to experimental variation of environmental quality during ontogeny. Individuals of the cichlid fish Simochromis pleurospilus that experienced a change in food ration early in life outperformed fish kept on constant rations in a learning task later in life--irrespective of the direction of the implemented change and the mean rations received. This difference in learning abilities between individuals remained constant between juvenile and adult stages of the same fish tested 1 y apart. Neither environmental enrichment nor training through repeated neural stimulation can explain our findings, as the sensory environment was kept constant and resource availability was changed only once. Instead, our results indicate a pathway by which a single change in resource availability early in life permanently enhances the learning abilities of animals. Early perturbations of environmental quality may signal the developing individual that it lives in a changing world, requiring increased cognitive abilities to construct adequate behavioral responses.
Kotrschal
Alexander
A
Behavioral Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland. alexander.kotrschal@iee.unibe.ch
Taborsky
Barbara
B
D000223:Adaptation, Psychological / Q000502:physiology; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D023681:Cichlids; D003071:Cognition / Q000502:physiology*; D004777:Environment; D005247:Feeding Behavior / Q000502:physiology; D005260:Female; D007858:Learning / Q000502:physiology*; D008297:Male
Am J Clin Nutr. 2000 Jun;71(6 Suppl):1669S-75S
10837313
Biol Lett. 2006 Jun 22;2(2):225-8
17148368
Behav Brain Res. 1997 Jun;86(1):113-20
9105589
Eur J Neurosci. 2004 Sep;20(5):1355-62
15341607
Psychol Rev. 1949 Jan;56(1):51-65
18124807
Neuroscience. 2003;118(2):571-6
12699791
PLoS Biol. 2006 Jul;4(8):e251
16834460
Epilepsy Behav. 2004 Aug;5(4):446-54
15256180
Proc Biol Sci. 2006 Mar 22;273(1587):741-50
16608695
Proc Nutr Soc. 2002 Feb;61(1):61-9
12002796
Nature. 1997 Apr 3;386(6624):493-5
9087407
Proc Biol Sci. 2004 Nov 22;271(1555):2381-6
15556891
Trends Ecol Evol. 2001 May 1;16(5):254-260
11301155
Proc Biol Sci. 2005 Jun 7;272(1568):1107-13
16024371
Proc Nutr Soc. 1993 Feb;52(1):189-99
8493264
Lancet. 1992 Feb 1;339(8788):261-4
1346280
Curr Biol. 2009 Jul 14;19(13):1151-5
19464180
Trends Neurosci. 1998 Dec;21(12):505-9
9881846