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<jats:title>Gobbled by Gobies</jats:title> <jats:p> A common feature of overfished marine ecosystems is a tendency for biomass to become dominated by jellyfish and microbes, and for the habitat to become anoxic or hypoxic as large fish species are removed. The Benguela ecosystem off the coast of Namibia is a case in point. <jats:bold> Utne-Palm <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="333" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190708">333</jats:related-article> ) describe how the loss of overfished sardines from the Benguela fishery has provided an opportunity for an endemic fish species, the bearded goby, to exploit jellyfish and microbial biomass and to increase in number. These small fish have in turn become the predominant prey species for the larger fish, birds, and mammals in the region. The significance of the goby lies in its ability to forage on resources traditionally regarded as “dead-ends.” The bearded goby has thus become a key stabilizing component to the turnover of energy in the Benguela ecosystem. </jats:p>

<jats:title>Transcription On and sORF</jats:title> <jats:p> Eukaryotic transcriptomes include numerous RNAs that are presumed noncoding because they include only short open reading frames (sORFs). However, some sORF RNAs actually produce small peptides with unknown activity. Now <jats:bold> Kondo <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="336" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188158">336</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5989" page="284" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1192769">Rosenberg</jats:related-article> </jats:bold> ) report the function of peptides containing 11 to 32 amino acids that are encoded by the gene <jats:italic>polished-rice</jats:italic> ( <jats:italic>pri</jats:italic> ). <jats:italic>pri</jats:italic> triggers N-terminal truncation of the transcription factor Shavenbaby that controls epidermal differentiation in <jats:italic>Drosophila</jats:italic> . Following <jats:italic>pri</jats:italic> expression, Shavenbaby is converted from a transcriptional repressor to an activator. Thus, sORF peptides can control transcriptional programs during embryonic development. </jats:p>

<jats:title>Hedgehog and Segmentation</jats:title> <jats:p> Segmentation is a key characteristic of body plan organization in some of the largest animal groups, including annelids, arthropods, and vertebrates, but its evolutionary origins remain debated. In arthropod embryos, the Hedgehog signaling pathway plays a crucial role in the axial patterning of developing segments. <jats:bold> Dray <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="339" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188913">339</jats:related-article> ) analyzed the function of this conserved pathway in the annelid worm <jats:italic>Platynereis</jats:italic> by using specific small molecule inhibitors and found a similar role for Hedgehog signaling in shaping segments in this animal. Thus, Hedgehog was involved in segment formation in the last common ancestor of the protostome animals, earlier in metazoan evolution than previously assumed. </jats:p>

<jats:title>Sulfur Signal Dinner</jats:title> <jats:p> Phytoplankton produces large amounts of the compound dimethylsulfoniopropionate (DMSP), which can be transformed into the gas dimethylsulfide and emitted into the atmosphere in sufficient quantities to affect cloud formation. The functional role of DMSP is somewhat unclear, but it is degraded by marine bacteria as a source of reduced carbon and sulfur. It also acts as a foraging cue for a variety of aquatic animals ranging from copepods to marine mammals. Now, <jats:bold> Seymour <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="342" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188418">342</jats:related-article> ) have developed a microfluidic device to observe the behavior of motile microorganisms in response to pulses of DMSP. Contrary to accepted thought, these compounds appear primarily to play a defensive role—for most motile organisms, they are strongly attractive and act as an important infochemical throughout the marine food web. </jats:p>

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