Summary: Bowen et al. (2012)

Individuals of a species, such as rats, may show defensive responses (hiding, fleeing, reduction in foraging) when exposed to predators or to predator-related cues. While individuals are also known to aggregate together, it is not yet known whether individuals with show these same responses in the presence of conspecifics. Bowen et al. (2012) investigated the defensive responses of rat dyads (two familiar individuals) and quads (four familiar individuals) to two stressors (bright ambient light and cat odour). They found that quads of rats responded to negative stimuli by huddling together (increased social proximity), but dyads did not show an increase in social proximity. Exposure to cat odour caused rats in both dyads and quads to decrease locomotor activity and increase defecation (signs of stress). Bowen et al. (2012) suggested that huddling is a defensive strategy for rats when they occur in larger groups, but not necessarily when they occur in pairs.

Summary: Zilles & Amunts (2012)

Zilles & Amunts (2012) review Chen et al. (2012) and Wedeen et al. (2012) to understand how the human brain is constructed and organized beyond the functional and cellular details. They note that these two separate papers rely on analysis of fibre pathway spatial course and the cortex's genetic topography. They highlight that the two studies "find unifying hierarchical and geometric rules behind the organizational details". Zilles & Amunts (2012) note that the brain appears to be highly regionally differentiated, but is also hierarchically and geometrically organized in its spatial organisation (referred to as "canonical brain organization"). They also note that this type of organization is altered by the prevailing environmental conditions (e.g. pathology and genetic diversity). They suggest the use of mathematical models to help understand the factors driving phenotypic variation.

Summary: Dzieweczynski et al (2012)

Communication between individuals is more likely to occur when they interact in groups, than when encountering individuals alone. However, other social factors might also influence communication between individuals. Dzieweczynski et al (2012) used Siamese fighting fish Betta splendens to investigate whether prior experience with an opponent influences the audience effect on male-male interactions. They found that males were more aggressive (opponent-directed gill flaring) when they were unfamiliar with each other and there were other males in the nearby vicinity. In contrast, they found that, when females were in the nearby vicinity, males made more opponent-directed tail beats, a behaviour more commonly associated with courtship than opponent-directed gill flaring. Dzieweczynski et al (2012) suggest that prior history with an opponent, in conjunction with the type of audience, can interact to influence aggressive interactions in Siamese fighting fish.

Summary: Durup & Thinus-Blanc (1987)

Durup & Thinus-Blanc (1987) investigated whether exploratory experience influences an individual golden hamster's (Mesocricetus auratus) ability to learn a shortcut. They allowed hamsters to explore two baited tables that could be accessed by a runway. Then, the animals were allowed to explore a shorter pathway that connected the two tables together. Finally, animals were given a choice between the longer pathway and two new shorter ones. Durup & Thinus-Blanc (1987) found that hamsters preferred the shortcut that did not cross over the previously experience linking path, or either of the two far portions that animals had linkage experience with. They suggest that prior experience of a linking element is important for establishing spatial relationships between objects and could be important for situational representation.

Summary: Leese (2012)

Prior to mating, pair bonding often occurs in monogamous animals. Leese (2012) tested the hypothesis that this behaviour allows for continuous partner (and potential other mates) quality assessment using the convict cichlid Amatitlania nigrofasciata. He allowed males and females to choose between their partners and novel individuals (opposite sex) at various times after pair bond formation. Leese (2012) found that females were more likely to remain with their partners, while males generally spent more time away from their partner with a novel female. However, this pattern differed with time spent in the pair bond. Males were initially very aggressive to novel females, while females initially ignored novel males. Even when individuals were given a "better option" (i.e. a larger mate), both males and females showed no preference. Leese (2012) suggests that pair bonding allows for continuous mate assessment by females, but not for males.

Summary: Anstee (1996)

The western pebble-mound mouse Pseudomys chapmani is a small conilurine rodent found throughout the Pilbara region of Western Australia. They construct mounds out of pebbles gathered from the surrounding areas. At any given time, not all mounds in a region might be occupied. Therefore, Anstee (1996) devised a scoring system, using the external features of the mound, to assess the likelihood that mounds are inhabited by mice. He found that mounds containing mice had a significantly higher index score than mounds without mouse and suggests that this scoring system is an effective predictor of P. chapmani presence within mounds.

Summary: Kemble et al. (1991)

Kemble et al. (1991) investigated how eltoprazine hydrochloride (DU 28853) influences exploratory behaviour and social attraction of conspecifics in mice. They found that exploratory behaviour was enhanced with drug treatment, but this also decreased conspecific social attraction. Kemble et al. (1991) suggest that eltroprazine, in contrast to another anxiogenic drug (fluprazine), ameliorates the neophobic response in mice. Similar to fluprazine, eltoprazine increases the aversive response to conspecifics. They suggest that this effect is mediated by alteration in olfactory function.