Consistent individual differences in associative learning speed are not linked to boldness in female Atlantic mollies
Recent studies on consistent individual differences in behavioural tendencies (animal personality) raised the question of whether individual differences in cognitive abilities can be linked to certain personality types. We tested female Atlantic mollies (Poecilia mexicana) in two different classical conditioning experiments. For the first time, we provide evidence for highly consistent individual differences in associative learning speed in fish. We characterized the same individuals for boldness in two experimental situations (latency to emerge from shelter and freezing time after a simulated predator attack) and found high behavioural repeatability. When we tested for a potential correlation between associative learning speed and boldness, however, there was no evidence for a link between them. Our study design included several steps to avoid typical pitfalls of disadvantaging shy individuals during learning tests. We caution that other experimental studies may have suffered from erroneous interpretations due to a more cautious coping style of shy individuals in the respective setup used to assess learning.
KeywordsCognitive syndrome Animal personality Classical conditioning Poeciliidae
We thank Holger Geupel and Eva Maria Wörner for help with animal care.
CST designed the study, collected data and conducted the statistical analyses. Both authors wrote the article.
Compliance with ethical standards
All applicable national and institutional guidelines for the care and use of animals were followed. All experiments comply with current German law and were approved by Regierungspräsidium Darmstadt (V-54-19c-20/15-F104/Anz.18). Both authors declare that they have no conflict of interest and agree upon the content of the article.
The dataset supporting this article will be uploaded as an additional spread sheet in the electronic supplemental material upon acceptance.
Conflict of interest
Carolin Sommer-Trembo declares that she has no conflict of interest. Martin Plath declares that he has no conflict of interest.
- Evans JP, Pilastro A, Schlupp I (eds) (2010) Ecology and evolution of poeciliid fishes. University of Chicago Press, ChicagoGoogle Scholar
- Gray JA (1964) Strength of the nervous system and levels of arousal: a reinterpretation. In: Gray JA, Eyesenck HJ (eds) Pavlov’s typology: recent theoretical and experimental developments from the laboratory of B.M. Teplov. Pergamon Press, OxfordGoogle Scholar
- Ibi D, Takuma K, Koike H, Mizoguchi H, Tsuritani K, Kuwahara Y, Kamei H, Nagai T, Yoneda Y, Nabeshima T, Yamada K (2008) Social isolation rearing-induced impairment of the hippocampal neurogenesis is associated with deficits in spatial memory and emotion-related behaviors in juvenile mice. J Neurochem 105:921–932CrossRefPubMedGoogle Scholar
- Locurto C (2007) Individual differences and animal personality. Comp Cogn Behav Rev 2:67–78Google Scholar
- Petrazzini MEM, Agrillo C (2016) Turning to the larger shoal: are there individual differences in small-and large-quantity discrimination of guppies? Ethol Ecol Evol 28:211–220Google Scholar
- Plath M, Pfenninger M, Lerp H, Riesch R, Eschenbrenner C, Slattery PA, Bierbach D, Herrmann N, Schulte M, Arias-Rodriguez L, Rimber Indy J, Passow C, Tobler M (2013) Genetic differentiation and selection against migrants in evolutionarily replicated extreme environments. Evolution 67:2647–2661CrossRefPubMedGoogle Scholar
- Toms CN, Echevarria DJ, Jouandot DJ (2010) A methodological review of personality-related studies in fish: focus on the shy-bold axis of behavior. Int J Comp Psychol 23:1–25Google Scholar