Striped mouse

Striped mouse

Striped mouse (Rhabdomys pumilio) on the cover of the August edition of Behaviour

Striped mouse (Rhabdomys pumilio) on the cover of the August edition of Behaviour
My photo and the accompanying paper (see List of publications) were published in this issue.

Sunday, March 11, 2012

Summary: Sulikowski & Burke (2012)

 In foraging behaviour terminology, win-shifting consists of avoidance of locations that have yielded food recently while win-staying consists of active return to these locations. Numerous nectarivorous bird species have shown to be biased towards win-shifting, suggesting that this might be a candidate for a cognitive adaptive specialisation (since food resources that have been exploited recently will not necessarily be available). Sulikowksi & Burke (2012) demonstrated that noisy miners Manorina melanocephala and rainbow lorikeets Trichoglossus haematodus with prior reinforcement of win-shifting or win-staying maintained these preferences, although poorer performance was not necessarily a consequence of an inability to learn the win-stay event. Their results suggest that birds are sensitive to both strategies, implying that the adapted mechanisms (cognitive adaptation) may result from an inhibition of the win-stay response, rather than a lack of sensitivity to win-stay strategies.

Thursday, March 8, 2012

Summary: Kasanetz et al. (2010)

 Numerous studies have shown that brain physiology is modified in a numerous ways through chronic exposure to illegal substances (i.e. drugs of abuse). Since some individuals are more likely to become addicts than others, this raises the question of which neurobiological adaptations are associated with a shift from no-addict to addict. Kasanetz et al. (2010) noted that long-term depression (LTD) can be suppressed through self-administration of cocaine and this is related to synaptic plasticity in the region of the nucleus accumbens. They found that rats that are likely to become addicts have permanently impaired LTD, while rats that are unlikely to become addicts show progressive recovering in LTD. Kasanetz et al. (2010) suggest that the transition to addiction could be mediated by a persistently impaired LTD when drug seeking behaviour is made consistently resistant to modulation by possible environmental changes.

Wednesday, February 29, 2012

Summary: Gonçalves et al. (2012)

The white seabream Diplodus sargus is an economically important fish that shows high levels of aggression in captivity, making aquaculture difficult. In this study, Gonçalves et al. (2012) assessed growth rate and dominance hierarchies in seabream to test whether stable dominance orders can be established in captivity and whether dominance status affects rate of growth and body condition. They established 8 groups consisting of 6 individuals and measured the linearity of hierarchies every week, and the stability of these hierarchies on a week-to-week basis, for 6 weeks. They found that the dominance structures followed a linear pattern and were stable between weeks. However, there was no significant correlation between the dominance index and both growth rate and final body condition. They conclude that aggressive competition is not the primary cause in growth differences, although longer term effects induced by stress may be contributing factors.

Sunday, February 26, 2012

Summary: Kelley & Endler (2012)

Visual illusions are created when object or scene geometry is changed to trick the perception of the viewer when observing that scene/object from a specific direction. While many studies on sexual selection aim to compare signal strength, the components of the signal, and the processing of the information by the receiver's senses may interact to form visual illusions that are misleading (or are designed to capture attention). Kelley & Endler (2012) found that male great bowerbirds Ptilonorhynchus nuchalis create forced-perspective illlusions to female perceiver's in the bower avenue by actively maintaining size-distance gradients of the objects they use to create the bower court. They found that mating success and the female's perception of the gradient are significantly related and suggest that the use of illusions in mating and courtship might be more widespread than originally thought, based on orientation and distance characteristics used by males of multiple species.

Thursday, February 23, 2012

Summary: Maciá et al. (2004)

In this short note, Maciá et al. (2004) report new observations of flying behaviour in the Caribbean reef squid Sepioteuthis sepioidea. They distinguish between flying and gliding this type of airborne jet propulsion appears more active than simply gliding. S. sepioidea have previously been considered incapable of flight, due to their large body size. Maciá et al. (2004) also review previous accounts of flying behaviour in other squid species. They note several instances of flying behaviour in squid and indicate that S. sepioidea can indeed fly up to 50 times their own body length (20-25 cm). They note that this behaviour appears to be more widespread that initially suspected.

Tuesday, February 21, 2012

Summary: Fleming et al. (2012)

Extensive cytological and molecular changes occur at conception, particularly at the time of ovulation, fertilization and embryonic development. While this progression is generally programmed by intrinsic processes, environmental factors impart important information on the metabolic process, influencing the developmental programme. Fleming et al. (2012) review a variety of mammalian models and suggest that maternal nutrition modifies this developmental process throughout the gestatory period through its mediation of the peri-conceptual environment and that this can affect the physiological and metabolic health of the offspring when they reach adulthood. They indicate that the origin of adult disease risk might be a function of the quality of the mother's nutrition prior to parturition and suggest that more research on the mechanisms are required if preventative strategies for managing disease risk are to be implemented.

Monday, February 6, 2012

Summary: Ackerman et al. (2010)

The first sense to develop is touch, and it is a critical means of manipulating the environment and acquiring information. Physically touching objects allows for the development of both intra- and interpersonal conceptual and metaphorical knowledge and provide the platform for knowledge application. Impressions and decisions formed about strangers and novel situations were nonconsciously influenced when an individual experienced objects of varying weights and textures. Ackerman et al. (2010) found that job candidates appeared more important if they held heavy objects, while social interactions were more challenging when rough objects were held. Furthermore, holding hard objects increased negotiation rigiditiy. They suggest that higher social cognitive processing is influenced by basic tactile sensations in both metaphor- and dimension-specific ways.