Pluralism in evolutionary controversies: styles and averaging strategies in hierarchical selection theories

Two controversies exist regarding the appropriate characterization of hierarchical and adaptive evolution in natural populations. In biology, there is the Wright–Fisher controversy over the relative roles of random genetic drift, natural selection, population structure, and interdemic selection in adaptive evolution begun by Sewall Wright and Ronald Aylmer Fisher. There is also the Units of Selection debate, spanning both the biological and the philosophical literature and including the impassioned group-selection debate. Why do these two discourses exist separately, and interact relatively little? We postulate that the reason for this schism can be found in the differing focus of each controversy, a deep difference itself determined by distinct general styles of scientific research guiding each discourse. That is, the Wright–Fisher debate focuses on adaptive process, and tends to be instructed by the mathematical modeling style, while the focus of the Units of Selection controversy is adaptive product, and is typically guided by the function style. The differences between the two discourses can be usefully tracked by examining their interpretations of two contested strategies for theorizing hierarchical selection: horizontal and vertical averaging.     

Serum albumin acts as a shuttle to enhance cholesterol efflux from cells

An important mechanism contributing to cell cholesterol efflux is aqueous transfer in which cholesterol diffuses from cells into the aqueous phase and becomes incorporated into an acceptor particle. Some compounds can enhance diffusion by acting as shuttles transferring cholesterol to cholesterol acceptors, which act as cholesterol sinks. We have examined whether particles in serum can enhance cholesterol efflux by acting as shuttles. This task was accomplished by incubating radiolabeled J774 cells with increasing concentrations of lipoprotein-depleted sera (LPDS) or components present in serum as shuttles and a constant amount of LDL, small unilamellar vesicles, or red blood cells (RBC) as sinks. Synergistic efflux was measured as the difference in fractional efflux in excess of that predicted by the addition of the individual efflux values of sink and shuttle alone. Synergistic efflux was obtained when LPDS was incubated with cells and LDL. When different components of LPDS were used as shuttles, albumin produced synergistic efflux, while apoA-I did not. A synergistic effect was also obtained when RBC was used as the sink and albumin as shuttle. The previously observed negative association of albumin with coronary artery disease might be linked to reduced cholesterol shuttling that would occur when serum albumin levels are low.     

Dramatic changes in the return date of Guillemots Uria aalge to colonies in Shetland, 1962–2005

Capsule Changes in return date coincided with marked changes in population size that probably resulted in fluctuating competition for nest-sites.

Aims To document the changes in return dates over a 44-year period and to identify the factors associated with these changes.

Methods We compared changes in return date at Shetland colonies with those for the Isle of May, southeast Scotland, and with the available information on population size, the abundance of some fish species eaten by Common Guillemots and large-scale changes in the oceanography and climate of the eastern Atlantic as reflected by the winter index of the North Atlantic Oscillation (NAO).

Results Common Guillemots normally return to colonies in Shetland in late winter. However, during the 1960s return dates became gradually earlier with birds present from early October. Autumn return remained the norm for about ten years after which return dates gradually reverted back to late winter. In contrast, Common Guillemots on the Isle of May, 400 km south of Shetland, showed no marked shift, returning in October each year. There was a strong negative correlation between date of return of Shetland birds and population size, whereas on the Isle of May birds came back earlier when there was a large positive winter NAO index. There was no convincing evidence that changes in wintering areas or fish abundance influenced when birds returned to the colonies, although the fish data may not have been collected on the correct spatial scale.

Conclusion Competition for high quality nest-sites is the most likely reason for Common Guillemots returning to the colonies during the autumn and winter.     

China Art by Phone: Mobile Movies

Jia ZhangKe's film Platform gives crystalline shape to a generation in a group of youth gathered around a tape-recorder in Fenyang city. The tape itself had come from Guangzhou and before that, presumably, from across the border with Hong Kong. Perhaps a Cantonese filtering, a local expression of Western and brand-name product that, viewed positively, marks the largest and most sweeping educational drive in China's history, the distribution and assimilation of fashion, DVDs, CDs, video, and design. This article seeks to know empirically the conditions that lay the groundwork for this educational drive, focusing on social transformation and the impact of digital technologies on theory, approach, practice, consumption. Clearly, mobility is important in this process of social transformation. Platform gives us images of the mobility of people, things, and ideas. This article also looks at the effects of the transport of people, things, and ideas and explores the cultural dimensions of social transformation. The article asks: What is mobility for artists and media producers? What are the urbanistic interconnections that emerge from an engagement with public space? These questions are explored around the social and cultural terrain of the mobile phone.

The article considers the virtual public space of the mobile telephone now opening to cultural producers and consumers. In what way does the mobile telephone, as an instrument for dialogue, a marketing device, and a promotional tool, affect our perception of public space? This article examines several initiatives that bring the mobile phone and cultural production together. One of these is titled “Focus: This Moment,” a program of eight short films by eight contemporary Chinese film directors made for mobile phone and Internet distribution. Another is “Connect to Art,” initiated by Nokia in September 2004 in Helsinki, continued in Monaco in December 2004, and then furthered again in Shanghai in May 2006 with the unveiling of four works by Chinese contemporary artists: Ai Weiwei, Yang Fudong, Zhang Peili, and Feng Mengbo. The article considers how mobile phone movies modify and enrich our understanding of cinema. This is thus an enquiry into the impact of digital technology on the mature film industry. Furthermore, the article asks how public space is enfolded in multiple contextual discourses that create the mobility and interface of the mobile phone.