The Differentiating Behaviour of Shoppers: Clustering of individual movement traces in a supermarket

In this paper we report on research into patterns of shopper movement and behaviour in a supermarket. It is an underlying assumption of much space syntax research that the population is relatively homogeneous in terms of the way it uses space, introduced by the theory of natural movement in urban environments where the density distribution of facilities varies and the spatial configuration is diverse. However, in the specific case of a supermarket where goods are very evenly distributed in a regular and even grid, we need to explore the variations in individual behaviour within the population to understand the movement patterns in the store. Using data of over 480 shoppers interviewed and individually tracked in their shopping trip in a supermarket, we develop methods of profiling different shoppers according to both demographic and behavioural factors. We show that there are distinct clusters of shopping strategy defined in terms of characteristic search trail through the store, and that these correlate with specific shopper profile. We conclude that in situations where the allocation of attractors to space is neither random nor correlated to spatial structure, different groups of people on different kinds of mission will adopt distinctive spatial behaviour. This suggests that the assumption of homogeneity may be ill founded, at least under these circumstances

Social Status Affects the Degree of Sex Difference in the Songbird Brain

It is thought that neural sex differences are functionally related to sex differences in the behaviour of vertebrates. A prominent example is the song control system of songbirds. Inter-specific comparisons have led to the hypothesis that sex differences in song nuclei size correlate with sex differences in song behaviour. However, only few species with similar song behaviour in both sexes have been investigated and not all data fit the hypothesis. We investigated the proposed structure – function relationship in a cooperatively breeding and duetting songbird, the white-browed sparrow weaver (Plocepasser mahali). This species lives in groups of 2–10 individuals, with a dominant breeding pair and male and female subordinates. While all male and female group members sing duet and chorus song, a male, once it has reached the dominant position in the group, sings an additional type of song that comprises a distinct and large syllable repertoire. Here we show for both types of male – female comparisons a male-biased sex difference in neuroanatomy of areas of the song production pathway (HVC and RA) that does not correlate with the observed polymorphism in song behaviour. In contrast, in situ hybridisation of mRNA of selected genes expressed in the song nucleus HVC reveals a gene expression pattern that is either similar between sexes in female – subordinate male comparisons or female-biased in female – dominant male comparisons. Thus, the polymorphic gene expression pattern would fit the sex- and status-related song behaviour. However, this implies that once a male has become dominant it produces the duetting song with a different neural phenotype than subordinate males