The link between relative brain size and cognitive ageing in female guppies (Poecilia reticulata) artificially selected for variation in brain size
Autor: | Annika Boussard, Alexander Kotrschal, Severine D. Buechel, Mirjam Amcoff, Niclas Kolm |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
0301 basic medicine
Senescence Aging Behavioural flexibility Biology Affect (psychology) Biochemistry 03 medical and health sciences Behavioral Ecology Cognition 0302 clinical medicine Endocrinology Reversal learning Genetics Animals Sexual maturity Molecular Biology Poecilia Life length Brain Flexibility (personality) Organ Size Cell Biology Gedragsecologie 030104 developmental biology Cognitive Aging Ageing Brain size WIAS Female 030217 neurology & neurosurgery Demography |
Zdroj: | Experimental Gerontology, 146 Experimental Gerontology 146 (2021) |
ISSN: | 0531-5565 |
DOI: | 10.1016/j.exger.2020.111218 |
Popis: | Cognitive ageing is the general process when certain mental skills gradually deteriorate with age. Across species, there is a pattern of a slower brain structure degradation rate in large-brained species. Hence, having a larger brain might buffer the impact of cognitive ageing and positively affect survival at older age. However, few studies have investigated the link between relative brain size and cognitive ageing at the intraspecific level. In particular, experimental data on how brain size affects brain function also into higher age is largely missing. We used 288 female guppies (Poecilia reticulata), artificially selected for large and small relative brain size, to investigate variation in colour discrimination and behavioural flexibility, at 4–6, 12 and 24 months of age. These ages are particularly interesting since they cover the life span from sexual maturation until maximal life length under natural conditions. We found no evidence for a slower cognitive ageing rate in large-brained females in neither initial colour discrimination nor reversal learning. Behavioural flexibility was predicted by large relative brain size in the youngest group, but the effect of brain size disappeared with increasing age. This result suggests that cognitive ageing rate is faster in large-brained female guppies, potentially due to the faster ageing and shorter lifespan in the large-brained selection lines. It also means that cognition levels align across different brain sizes with older age. We conclude that there are cognitive consequences of ageing that vary with relative brain size in advanced learning abilities, whereas fundamental aspects of learning can be maintained throughout the ecologically relevant life span. |
Databáze: | OpenAIRE |
Externí odkaz: |