I see someone who looks vaguely familiar. I wonder if he could be the same person I had a fight with on my birthday ten years ago. I hear that some scientist has received the Nobel prize in chemistry for some work very similar to that which interested the brightest boy in my chemistry class twenty years ago. I wonder if that scientist and the brightest boy might be the same person. What facts, if they could be discovered, would be decisive in answering these questions? Are there any facts that, if it turns out that they do not obtain, would show conclusively that the two people are not the same person? That is, are there any necessary conditions for personal identity? Are there any facts that, if it turns out that they do obtain, would show conclusively that the two people are the same person? That is, are there any sufficient conditions for personal identity?

The ribosome is the location of protein translation and therefore a pivotal macromolecular complex for all organisms. The RNA molecules involved in the formation and functioning of the ribosome (rRNA) are partially single-stranded (loops) and partially double-stranded (helices or stems) as a result of pairing of complementary regions in either their own or other rRNA subunits. This pattern provides the rRNA with a secondary structure crucial for its functionality. The stability of these secondary structures is mediated by their base compositions: a helix rich in G-C pairs possesses a higher thermodynamic stability than an A-T rich counterpart. However, the base composition of these structures is neither homogeneous throughout the molecule nor throughout the demosponge taxa. Here, we present patterns of biased nucleotide composition in demosponge 28S rDNA. We analyse their correlation in respect to environment and taxonomy. We find significantly higher G+C contents in haplosclerid demosponges compared to other orders and investigate evidence for an association between water temperature and rRNA base composition in demosponges.

We present a 28S rDNA gene tree of selected Raspailiidae, Axinellidae and other demosponges to obtain insight into raspailiid phylogeny and character evolution. The Raspailiidae in our data set cluster in a well-supported clade, distinguished from Axinellidae, Agelasida and Hadromerida. Raspailia (s.s.), Eurypon, Sollasella, Aulospongus and Ectyoplasia form a Raspailiidae clade. Some Raspailia subgenera, in particular R. (Parasyringella), are not retrieved monophyletically. Trikentrion falls into the Thrinacophorinae, and not the Cyamoninae as earlier hypothesized. The axinellid genera Ptilocaulis and Reniochalina also cluster with Raspailiidae, distant from the other Axinellidae. The suitability of particular morphological characters for raspailiid phylogeny is discussed.

The aim of Working Group 5 is to develop and coordinate education and support networks for individuals and organizations undertaking or using assessment of health interventions and to identify needs in the field and assist in the establishment of new provisions.