Development of the Social Behavior of Two Mice Species With Contrasting Social Systems

The house mouse (Mus musculus) and the mound‐building mouse (M. spicilegus) differ in their mating and social systems. The M. musculus is polygynous and females tend to breed cooperatively while M. spicilegus is known to be monogamous and famous for its unique cooperative behavior; the communal overwintering. Mus spicilegus is considered as a highly aggressive species in the genus Mus. In the present study, we attempted to analyze the development of aggressive and sociable behavior in these species and to discover how familiarity with the target moderates the development of sociable and aggressive behaviors and moderates the differences between the species. Dyadic social interaction tests in neutral cages were performed on 21‐, 60‐, and 120‐day‐old mice of both genders and both species. Each individual was tested against a sibling and an unfamiliar individual at all three ages. Our results showed that the development of aggressive and sociable behavior with age differed between the species and sexes; however, familiarity with the other mouse moderated the effect of species on aggression. At 21 days, both genders of M. spicilegus were more aggressive against strangers than siblings. This became true of both species at 60 days. When facing a stranger, both sexes of M. spicilegus were more aggressive than M. musculus at 120 days. However, when facing a sibling, neither gender of M. spicilegus was more agonistic than M. musculus, indicating that either kinship or early social experiences elicit tolerance. Aggr. Behav. 38:288‐297, 2012. © 2012 Wiley Periodicals, Inc.     

Can but don’t: olfactory discrimination between own and alien offspring in the domestic cat

Mammalian maternal care usually comes at a large energetic cost. To maximize their fitness, mothers should preferentially care for their own offspring. However, the majority of studies of mother–offspring recognition have focused on herd- or colony-living species and there is little information on maternal discrimination in more solitary-living species. Olfaction has been found to play a major role in mother–offspring recognition across various taxa. Therefore, our aim was to study this in a species evolved from a solitary-living ancestor, the domestic cat. We asked whether cat mothers distinguish between their own and alien offspring when providing maternal care, and whether cat mothers use olfactory cues in the offspring discrimination process. Results of Experiment 1 showed that cat mothers do not discriminate between own and alien young when retrieving them to the nest. They treated own and alien young similarly with respect to latency and order of retrieval. However, the results of Experiments 2 and 3, where we used an olfactory habituation-discrimination technique, showed that mothers were able to distinguish between the odours of their own and alien kittens. We discuss what ecological and/or behavioural factors might influence a mother’s decision when faced with discriminating between own and alien young, and why mothers might not discriminate between them when they are able to do so. Our findings support the view that maternal care alone should not be used as a measure of offspring recognition, and equal maternal care of own and alien young should not be immediately interpreted as an inability to discriminate between them.     

Olfactory discrimination between litter mates by mothers and alien adult cats: lump or split?

Animal Cognition - Mother cats can discriminate between their own and alien kittens using kittens’ body odour. Here we ask whether they can also distinguish between body odours of kittens...     

More or less: spontaneous quantity discrimination in the domestic cat

We examined spontaneous quantity discrimination in untrained domestic cats in three food choice experiments. In Experiment 1, we presented the cats with two different quantities of food in eight numerical combinations. Overall, the subjects chose the larger quantity more often than the smaller one, and significantly so when the ratio between the quantities was less than 0.5. In Experiment 2, we presented the cats with two pieces of food in four different size combinations. Again, subjects chose the larger piece above chance, although not in the combination where the largest item was presented. In Experiment 3, a subset of the cats was presented multiple times with two different quantities of food, which were hidden from view. In this case, the cats did not choose the larger quantity more often than the smaller one, suggesting that in the present experiments they mainly used visual cues when comparing quantities. We conclude that domestic cats are capable of spontaneously discriminating quantities when faced with different numbers or sizes of food items, and we suggest why they may not always be motivated to choose the larger quantity. In doing so, we highlight the advantages of testing spontaneous choice behavior, which is more likely to reflect animals’ everyday manner of responding than is the case when training them in order to test their absolute limits of performance which may not always coincide with their daily needs.     

Quantity discrimination by kittens of the domestic cat (Felis silvestris catus)

Animal Cognition - Quantitative abilities are well described in many species and in diverse life situations, including in the adult domestic cat. However, such abilities have been much less studied...     

Are you my mummy? Long-term olfactory memory of mother’s body odour by offspring in the domestic cat

Animal Cognition - Longevity of odour memories, particularly those acquired during early development, has been documented in a wide range of taxa. Here, we report that kittens of the domestic cat...