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<jats:p>It will take vigilance, commitment, and action by all global stakeholders to reduce the potential impact of pandemic influenza during the upcoming Hajj pilgrimage.</jats:p>

<jats:p>Using carbon markets to eliminate substances that deplete stratospheric ozone could pay huge dividends in combating global warming.</jats:p>

<jats:p>Electron microscopy is providing glimpses of the complex structural processes that precede crystal nucleation.</jats:p>

<jats:p>The lack of security in cyberspace may be addressed by learning from the strengths of the Internet.</jats:p>

<jats:p>Two gene families in the worm control survival strategies in response to stressful environmental conditions.</jats:p>

<jats:p>A little-understood electron flow pathway helps cyanobacteria to adapt to high-light, low-nutrient ocean environments.</jats:p>

<jats:p>The leadership, political skills, and commitment of the first woman director at the U.S. National Institutes of Health are unrivaled.</jats:p>

<jats:p>The ends of eukaryotic chromosomes have the potential to be mistaken for damaged or broken DNA and must therefore be protected from cellular DNA damage response pathways. Otherwise, cells might permanently arrest in the cell cycle, and attempts to “repair” the chromosome ends would have devastating consequences for genome integrity. This end-protection problem is solved by protein-DNA complexes called telomeres. Studies of mammalian cells have recently uncovered the mechanism by which telomeres disguise the chromosome ends. Comparison to unicellular eukaryotes reveals key differences in the DNA damage response systems that inadvertently threaten chromosome ends. Telomeres appear to be tailored to these variations, explaining their variable structure and composition.</jats:p>

<jats:p>Once thought to be an oddity, small catalytic RNAs have been found in a wide range of organisms.</jats:p>

<jats:title>Life Histories to Suit</jats:title> <jats:p> Nematode worms can profoundly manipulate their life histories in several ways. For example, <jats:italic>Caenorhabditis elegans</jats:italic> has two genders: males and hermaphrodites. Some clues for the evolution of this peculiar mating system have been revealed by <jats:bold> Baldi <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1002" related-article-type="in-this-issue" vol="326" xlink:href="10.1126/science.1176013">1002</jats:related-article> ), who turned females of a related species, <jats:italic>Caenorhabditis remanei</jats:italic> , into hermaphrodites by modifying a gene involved in making sperm and another gene required for activating the spermatids. In most animals, the germ line is fully established during adulthood and a reproductive period is determined, at least in part, by aging of the germ line and the viability of oocytes. The reproductive longevity of hermaphrodite <jats:italic>C. elegans</jats:italic> can be increased at least 15-fold by starvation. <jats:bold>Angelo and Van Gilst</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="954" related-article-type="in-this-issue" vol="326" xlink:href="10.1126/science.1178343">954</jats:related-article> , published online 27 August; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5955" page="944" related-article-type="in-this-issue" vol="326" xlink:href="10.1126/science.1183272">Ogawa and Sommer</jats:related-article> </jats:bold> ) found that in starved worms, the germline component of the reproductive system is actively killed, with the exception of a small set of preserved stem cells. When the worms are able to feed again, these cells regenerate into an entirely new and functional germ line. But this is not all. <jats:bold> Kim <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="994" related-article-type="in-this-issue" vol="326" xlink:href="10.1126/science.1176331">994</jats:related-article> , published online 1 October; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5955" page="944" related-article-type="in-this-issue" vol="326" xlink:href="10.1126/science.1183272"> <jats:bold>Ogawa and Sommer</jats:bold> </jats:related-article> </jats:bold> ) show that subsets of the complex mixture of structurally related molecules in dauer pheromone act via distinct G protein–coupled receptors either to initiate longterm effects on development and physiology by modulating the neuroendocrine axis, or to trigger short-term acute effects on behavior by altering neuronal responses. </jats:p>