Molecular and morphological evolution of the amphipod radiation of Lake Baikal

The amphipods of Lake Baikal, Russia, are a taxonomically and morphologically diverse group, and have been cited as a classic example of adaptive radiation. An unfortunate consequence of this diversity has been an instability of Baikal amphipod classification, with frequent revisions spurred by differing opinions about the phylogenetic utility of different characters. Classifications have never been based on a rigorous phylogenetic analysis of morphological data and only recently has the phylogeny of Lake Baikal\u27s amphipods been examined using molecular tools. Unfortunately, most of these studies have led to a limited expansion of our understanding of Baikal amphipod systematics. Phylogenetic relationships of selected amphipod species from Lake Baikal were constructed using molecular data from portions of two mitochondrial genes, 16S rDNA and COI, and 121 morphological characters. Additionally, patterns of morphological change and the phylogenetic utility of different characters were examined by tracing the 121 morphological characters upon the most parsimonious 16S phylogeny. While the molecular datasets resulted in similar topologies, the morphological data were not congruent with either molecular dataset. A combined molecular/morphological analysis resulted in a topology that was not very different than the combined molecular phylogeny. When plotted on the most parsimonious 16S tree, the morphological data was very homoplastic, although the level of homoplasy differed among types of morphological characters. Contrary to recent popular opinion, body armour and processes characters were the least homoplastic of all types, while characters that have been considered phylogenetically useful, such as mouthpart characters, were the most homoplastic. The molecular phylogenies obtained in this study lead to a better understanding of the phylogenetic history of Baikal\u27s amphipods. The large, morphologically diverse family Acanthogammaridae is strongly supported as a monophyletic group, and likely to have radiated from a single ancestral species within the lake. Conversely, the fossorial, morphologically uniform family Micruropodidae seem to be composed of two relatively unrelated groups, one of which is closely related to the monotypic Macrohectopidae, the lake\u27s morphologically highly modified pelagic planktivore, suggesting a disjunction between morphological and molecular evolution. Finally, this study suggests that the amphipod fauna of Lake Baikal is not monophyletic; the cosmopolitan Gammarus lacustris may share recent common ancestry with some Baikal taxa

Biodiversity, host specificity, and dominance by eusocial species among sponge-dwelling alpheid shrimp on the Belize Barrier Reef

Alpheid shrimp represent an abundant and diverse, but poorly characterized, component of the cryptic biodiversity of coral reefs worldwide. Sponge-inhabiting alpheids provide a promising model system for exploring patterns of cryptic reef biodiversity because their habitats (hosts) are discrete and qualitatively distinct units. We tabulated data from 14 years of collections at Carrie Bow Cay, Belize to quantify patterns of diversity, host specificity, and dominance among sponge-dwelling shrimp (Synalpheus), with special attention to eusocial species. From \u3e 600 sampled sponges of 17 species, we recognized at least 36 Synalpheus shrimp species. Of these, 15 (42%) were new to science. Species accumulation curves suggest that we have sampled most of the Synalpheus diversity at Carrie Bow Cay. Diversity of sponge-dwelling Synalpheus was slightly higher in shallow water, probably because of greater habitat diversity, than in deep water. Host specificity was surprisingly high, with \u3e 50% of all shrimp species found in only a single sponge species each, although some shrimp species used as many as six hosts. Cohabitation of individual sponges by multiple shrimp species was rarer than expected by chance, supporting previous distributional and behavioural evidence that competition for hosts is strong and moulds patterns of host association. The fauna of most well-sampled sponge species was dominated, both in numbers of individuals and in frequency of occurrence, by eusocial species. Eusocial shrimp species also inhabited a significantly greater number of sponge species than did non-social shrimp. Consequently, \u3e 65% of shrimp in our quantitative samples belonged to the four eusocial species, and on a per-species basis, eusocial species were 17 times as abundant as non-social species. Our data suggest that the highly diverse sponge-dwelling shrimp assemblage of the Belize Barrier Reef is structured by competition, and that eusociality has allowed a small number of species to dominate the sponge resource

Decline and Local Extinction of Caribbean Eusocial Shrimp

The tropical shrimp genus Synalpheus includes the only eusocial marine animals. In much of the Caribbean, eusocial species have dominated the diverse fauna of sponge-dwelling shrimp in coral rubble for at least the past two decades. Here we document a recent, dramatic decline and apparent local extinction of eusocial shrimp species on the Belize Barrier Reef. Our collections from shallow reefs in central Belize in 2012 failed to locate three of the four eusocial species formerly abundant in the area, and showed steep declines in colony size and increases in frequency of queenless colonies prior to their disappearance. Concordant with these declines, several nonsocial, pair-forming Synalpheus species increased in frequency. The decline in eusocial shrimp is explained in part by disappearance of two sponge species on which they specialize. Eusocial shrimp collections from Jamaica in 2012 showed similar patterns of decline in colony size and increased queenlessness compared with prior Jamaican collections. The decline and local extinction of eusocial shrimp happened against a backdrop of changes in coral assemblages during recent decades, and may reflect changes in abundance and quality of dead coral substratum and succession of the diverse cryptic organisms living within it. These changes document potentially worrisome declines in a unique taxon of eusocial marine animals

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Synalpheus androsi Coutiere 1909

Synalpheus androsi Coutière, 1909 Material examined. Barbados: 8 non-ovigerous individuals, 5 ovigerous females (VIMS 08BR 6706 –7, 08BR 6802 –3, 08BR 7101 – 2), Cement Factory, from Hyattella intestinalis. 1 non-ovigerous individual (VIMS 08BR 8002), Cluff Reef, from H. intestinalis. 12 non-ovigerous individuals, 5 ovigerous females (VIMS 08BR 1402 – 3 08 BR 1405 – 11), Spawnee Reef, from H. intestinalis. Largest ovigerous female, CL 4.08 mm, largest non-ovigerous individual, CL 3.78 mm. Color. Transparent, slightly opaque whitish, with olive-colored embryos (see Ríos and Duffy 2007, Plate 1). Hosts and ecology. As in Belize and Jamaica (Macdonald et al., 2006; Ríos and Duffy, 2007; Macdonald et al., 2009), in Barbados S. androsi lives only within the sponge Hyattella intestinalis, apparently in heterosexual pairs; we found up to five pairs of adults within a single sponge. Distribution. Bahamas (Coutière 1909); Belize (Macdonald et al. 2006; Ríos & Duffy 2007); Jamaica (Macdonald et al. 2009); Barbados (this study). Remarks. Synalpheus androsi can be easily distinguished from other species of Synalpheus living in H. intestinalis by the thin lateral flanges on flexor margins of the merus and carpus of the third and fourth pereopods.Published as part of Hultgren, Kristin M., Iii, Kenneth S Macdonald & Duffy, Emmett, 2011, Sponge-dwelling snapping shrimps (Alpheidae: Synalpheus) of Barbados, West Indies, with a description of a new eusocial species, pp. 1-16 in Zootaxa 2834 on page 5, DOI: 10.5281/zenodo.20807

Synalpheus williamsi Rios & Duffy 1999

Synalpheus williamsi Ríos & Duffy, 1999 Material examined. Barbados: 1 non-ovigerous individual, 1 ovigerous female (VIMS 08BR 7501 – 2), Cement Factory, from Hymeniacidon caerulea. 1 ovigerous female (VIMS 08BR 1412), Spawnee Reef, host unknown (in rubble with H. caerulea). 5 non-ovigerous individuals, 2 ovigerous females (VIMS 08BR 502 –3, 08BR1101, 08BR1103, 08BR1301, 08BR 2401), Spawnee Reef, from H. caerulea. 1 non-ovigerous individual (VIMS 08BR 1702), Spawnee Reef, host unknown (in rubble with H. caerulea). Largest ovigerous female, CL 3.44 mm, largest non-ovigerous individual, CL 2.85 mm. Color. The body color of S. williamsi ranged from almost colorless to dull orange, with distal portion of the major chela brilliant orange; ovaries were green, embryos bright orange-yellow. Hosts and ecology. In Barbados, S. williamsi appears to be a specialist in the sponge Hymeniacidon caerulea, as is the case in Belize and Jamaica (Macdonald et al. 2006; Ríos & Duffy 2007; Macdonald et al. 2009). Although some individuals were found in loose rubble or on the surface of other sponges embedded in rubble, the rubble always contained H. caerulea. Distribution. Jamaica (Macdonald et al. 2009); Curaçao (Hultgren et al. 2010); Belize (Macdonald et al. 2006; Ríos & Duffy 2007); Barbados (this study). Remarks. Synalpheus williamsi can be distinguished from other species of Synalpheus inhabiting the sponge Hymeniacidon caerulea by the number of spines on the uropod (3–6 fixed marginal teeth anterior to the moveable spine, vs. 1 fixed tooth in S. thele) or the relative length of the basicerite and scaphocerite spines (basicerite 75 % length of scaphocerite in S. ul).Published as part of Hultgren, Kristin M., Iii, Kenneth S Macdonald & Duffy, Emmett, 2011, Sponge-dwelling snapping shrimps (Alpheidae: Synalpheus) of Barbados, West Indies, with a description of a new eusocial species, pp. 1-16 in Zootaxa 2834 on page 14, DOI: 10.5281/zenodo.20807

Synalpheus sanctithomae Coutiere 1909

Synalpheus sanctithomae Coutière, 1909 Material examined. Barbados: 2 non-ovigerous individuals (VIMS 08BR 7103), Cement Factory, from Hyattella intestinalis. 4 non-ovigerous individuals, 1 ovigerous female (VIMS 08BR1001, 08BR 1201 – 2), Spawnee Reef, from Agelas clathrodes. 3 non-ovigerous individuals, 1 ovigerous female (VIMS 08BR 901 –2, 1901), Spawnee Reef, no host recorded. Largest ovigerous female, CL 3.43, largest non-ovigerous individual, CL 2.97 mm. Color. Ovigerous females had green ovaries and greenish-orange embryos and all individuals had a drab orange body color, deepening distally in their extremities, as in other locations (Ríos & Duffy 2007; Macdonald et al. 2009; Hultgren et al. 2010). Hosts and ecology. In Barbaros, S. sanctithomae lived in the sponges Hyattella intestinalis and Agelas clathrodes. Distribution. Florida, USA (Gore 1981); Virgin Islands (Coutière, 1909); Jamaica (Macdonald et al. 2009); Belize (Macdonald et al., 2006; Ríos & Duffy, 2007); Curaçao (Hultgren et al. 2010); Brazil (Christoffersen, 1979); Barbados (this study). Remarks. In Barbados, Synalpheus sanctithomae can be distinguished from the morphologically similar species S. mcclendoni by the number of setae on the posterior margin of the telson: a sparse tuft of <6 setae in S. sanctithomae vs. a well-developed fan of 10 or more setae in S. mcclendoni (Rios & Duffy 2007).Published as part of Hultgren, Kristin M., Iii, Kenneth S Macdonald & Duffy, Emmett, 2011, Sponge-dwelling snapping shrimps (Alpheidae: Synalpheus) of Barbados, West Indies, with a description of a new eusocial species, pp. 1-16 in Zootaxa 2834 on page 13, DOI: 10.5281/zenodo.20807

Synalpheus herricki Coutiere 1909

Synalpheus herricki Coutière, 1909 Material examined. Barbados: 2 ovigerous females, 4 non-ovigerous individuals (VIMS 08BR 8101 – 5), Cluff Reef, from Aiolochroia crassa. 2 ovigerous females, 4 non-ovigerous individuals (VIMS 08BR 1501 –2, 1601, 2101 – 2), Spawnee Reef, from A. crassa. 1 ovigerous female, 5 non-ovigerous individuals (VIMS 08BR 8901 – 3), Thunder Bay, from A. crassa. Largest ovigerous female, CL 6.46 mm, largest non-ovigerous individual, CL 5.33 mm. Color. In Barbados S. herricki had a drab, non-descript body color; ovigerous females had grass-green to brownish-green developing ovaries and embryos. Hosts and ecology. In Barbados, S. herricki only occurred in the common sponge Aiolochroia crassa. Distribution. Florida (Coutière 1909); Gulf of Mexico (Coutière 1909; Dardeau 1984); Belize (Ríos & Duffy 2007), Curaçao (Hultgren et al. 2010); possibly Brazil (Christoffersen 1998). Remarks. Many of the S. herricki collected in Barbados were juveniles. Some individuals had abdominal bopyrid parasites.Published as part of Hultgren, Kristin M., Iii, Kenneth S Macdonald & Duffy, Emmett, 2011, Sponge-dwelling snapping shrimps (Alpheidae: Synalpheus) of Barbados, West Indies, with a description of a new eusocial species, pp. 1-16 in Zootaxa 2834 on page 6, DOI: 10.5281/zenodo.20807