Implications of age variation and sexual dimorphism in modern equids for Middle Pleistocene equid taxonomy

Interspecific variation in the equid lineage is limited when compared with other large mammal lineages, while a considerable amount of intraspecific ecomorphological variation occurs. This has led to considerable debate regarding the taxonomic status of palaeontological and archaeological equid remains. The possible confounding impact of sex and age variation on analyses of archaeological equid remains has so far remained untested. This could be especially problematic when it is unknown whether an assemblage contains more than one equid species, breed or hybrid. Here, sex and age variation in modern equid species is examined and compared to variation in Pleistocene equid assemblages from northwest Europe. Sex variation in the longbones of modern equid species was found to be lower than variation over time. Similarly, age variation in dental elements of the same species is predominantly lower than diachronic variation, although caution needs to be taken when an archaeological assemblages consists mostly of elements at a similar wear stage. To assess whether late Middle Pleistocene caballoid horse fossils should be assigned to multiple species or be considered to form a monospecific group, the coefficients of variation for measurements on fossil horse remains were compared with those for modern equid specimens. Results indicate that the fossil assemblages are similarly variable to samples of modern material. Taken as a whole, the late Middle Pleistocene caballoid horse lineage is equally variable to an assemblage of modern ponies of a variety of different breeds. This implies that the variation observed between samples dating from different parts of the Middle Pleistocene can be characterised as intraspecific variation within a single species reflecting ecomorphological adaptations to the changeable Pleistocene climate. Copyright © 2010 John Wiley & Sons, Ltd.     

CREATIVE CLUSTERS IN BERLIN: ENTREPRENEURSHIP AND THE QUALITY OF PLACE IN PRENZLAUER BERG AND KREUZBERG

Urban creative clusters are currently a major focus of attention, as their prominent position in both local political and academic circles makes evident. Many authors stress the importance of spatial concentration for creative industries. However, only a few studies have focused on the individual entrepreneur. As a result, empirical evidence of the meaning of urban place as a site for social networks and a space for inspiration is still scarce. This is of some consequence as entrepreneurs provide a crucial link between creative activities and economic change and development. This study contributes to the existing literature by investigating how different creative entrepreneurs choose and evaluate their location. Using qualitative interviews with entrepreneurs in two creative clusters in the Berlin neighbourhoods Prenzlauer Berg and Kreuzberg, this article shows the significance of the look and feel of specific places and explains how and for whom local networks are important.     

Sampling seeds

Problems of sampling carbonized plant material are discussed. Firstly, the problem of actually selecting a sample in the laboratory is considered, and some experiments which investigate various procedures are described. Secondly, the statistical aspects of determining optimal sample sizes are considered. Formulae are given for calculating optimal sample sizes and confidence intervals. Upper bounds, which are independent of the total population size, are provided for the sample size required to achieve any desired accuracy.