Hooker and islands1

Sir Joseph Dalton Hooker (1817–1911), friend and scientific confidant of Charles Darwin, lectured in 1866 on ‘Insular floras’ at the Annual Meeting of the British Association for the Advancement of Science. His interest and knowledge of islands had been aroused when he travelled to the Antarctic aboard the Erebus under Sir James Clark Ross from 1839–43. On his return, Darwin passed on to Hooker the botanical collections he had made on the Beagle voyage, including those from the Galapagos. Hooker's conclusions from these and from his own material and experiences were important to Darwin as he developed the ideas that culminated in the publication of the Origin of Species. The 1866 lecture provided a focus for subsequent and informative studies on evolution, and islands continue to provide invaluable natural laboratories for evolutionary biology and genetics. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96 , 462–481.     

Public health in inner London.

One of Sir Bernard Tomlinson''s aims in his inquiry into London''s health services was to advise the secretary of state for health on the future balance of primary and secondary health care "taking account of the health needs of Londoners." Sir Bernard, however, also made it clear that "we have not seen it as part of our remit to carry out a comprehensive needs assessment for the whole of London," but concluded that the extremes of health need found in London were "unparalleled in the rest of England." Dr Jacobson highlights some of the major determinants of health inequality in inner London and assesses the extent to which the proposed solutions are likely to meet these needs.     

Histochemical studies on genetical control of hormonal enzyme inducibility in the mouse. III. Beta-glucuronidase distribution pattern of epididymis in different genotypes.

Synopsis This article reports the application of Hayashi's histochemical technique for -glucoronidase to mouse epididymis. A methodological study. which established optimal conditions for demonstrating the enzyme in this organ, is reported. The distribution pattern of -glucuronidase is described and correlated with previous data for -naphtyl acetate esterase. Differences between sites of granular and diffuse reaction product for these two enzymes are recorded. Possible interpretations of these findings in terms of intracellular localization of enzymes are discussed. Studies on different strains reveal regular differences in histochemical organization between mice of various genotypes. Histochemical data which imply androgen inducibility of -glucuronidase in mouse epididymis are preliminarily noted. Present address: Department of Anatomy, Faculty of Medicine, Sir Charles Tupper Medical Building, Dalhousie University, Halifax, Nova Scotia, Canada.     

London after Tomlinson. Clinical research.

Sir Bernard Tomlinson''s report focuses on London''s health services, but his proposals have major implications for the future of clinical research--not just in London but in the United Kingdom as a whole. They must be seen in the context of a widely perceived decline in British research and development which also threatens clinical research. This article examines the implications of Tomlinson''s proposals and related strategies and recommends the construction of a research market for the patient costs of clinical research to complement the NHS market for patient services introduced in 1991. These arrangements would help sustain the clinical research base and guarantee excellence.     

Dubin calls on CMPA to eliminate fee differentials,adopt flat fee for all physicians

Charles Dubin''s massive review of the Canadian Medical Protective Association supports the CMPA''s policy of maintaining a large reserve for malpractice coverage, but calls for a major overhaul of the association''s fee structure. Regardless of the risks their practices pose, says Dubin, all doctors should pay the same fee in order to keep physicians practising in high-risk specialties such as obstetrics and orthopedic surgery. The alternative, said CMPA president Dr. Bill Thomas, is an exodus from certain specialties because of massive bills for malpractice insurance.     

Dimerization of Sir3 via its C‐terminal winged helix domain is essential for yeast heterochromatin formation

Gene silencing in budding yeast relies on the binding of the Silent Information Regulator (Sir) complex to chromatin, which is mediated by extensive interactions between the Sir proteins and nucleosomes. Sir3, a divergent member of the AAA+ ATPase‐like family, contacts both the histone H4 tail and the nucleosome core. Here, we present the structure and function of the conserved C‐terminal domain of Sir3, comprising 138 amino acids. This module adopts a variant winged helix‐turn‐helix (wH) architecture that exists as a stable homodimer in solution. Mutagenesis shows that the self‐association mediated by this domain is essential for holo‐Sir3 dimerization. Its loss impairs Sir3 loading onto nucleosomes in vitro and eliminates silencing at telomeres and HM loci in vivo. Replacing the Sir3 wH domain with an unrelated bacterial dimerization motif restores both HM and telomeric repression in sir3Δ cells. In contrast, related wH domains of archaeal and human members of the Orc1/Sir3 family are monomeric and have DNA binding activity. We speculate that a dimerization function for the wH evolved with Sir3's ability to facilitate heterochromatin formation.     

Evolution and mechanisms of plant tolerance to flooding stress

Background

In recognition of the 200th anniversary of Charles Darwin''s birth, this short article on flooding stress acknowledges not only Darwin''s great contribution to the concept of evolution but also to the study of plant physiology. In modern biology, Darwin-inspired reductionist physiology continues to shed light on mechanisms that confer competitive advantage in many varied and challenging environments, including those where flooding is prevalent.

Scope

Mild flooding is experienced by most land plants but as its severity increases, fewer species are able to grow and survive. At the extreme, a highly exclusive aquatic lifestyle appears to have evolved numerous times over the past 120 million years. Although only 1–2% of angiosperms are aquatics, some of their adaptive characteristics are also seen in those adopting an amphibious lifestyle where flooding is less frequent. Lowland rice, the staple cereal for much of tropical Asia falls into this category. But, even amongst dry-land dwellers, or certain of their sub-populations, modest tolerance to occasional flooding is to be found, for example in wheat. The collection of papers summarized in this article describes advances to the understanding of mechanisms that explain flooding tolerance in aquatic, amphibious and dry-land plants. Work to develop more tolerant crops or manage flood-prone environments more effectively is also included. The experimental approaches range from molecular analyses, through biochemistry and metabolomics to whole-plant physiology, plant breeding and ecology.Key words: Abiotic stress, adaptation, anoxia, Charles Darwin, environmental stress, evolution, flooding, hypoxia, rice, submergence, wetlands     

October induction ceremony will coincide with official opening of Canadian Medical Hall of Fame

Seven of medicine''s leaders will be inducted into the Canadian Medical Hall of Fame during a special ceremony in London, Ont., on Oct. 5. The 1995 inductees are Drs. Henry Barnett, Bruce Chown, Herbert Jasper, Charles Leblond, William Mustard, Robert Salter and Michael Smith.     

The Oslerian Tradition and Changing Medical Education: A Reappraisal

Although only 21 of Sir William Osler''s 45 years in academic medicine were spent in US medical schools (1884 to 1905), he played a major role in shaping modern medical education in this country. The integration of scholarship with patient care, together with the science and art of medicine, was central to Osler''s teaching and writing throughout his career. A classic generalist and a charismatic clinical teacher, he taught by example and was as concerned with the ideals of medicine as with its science and knowledge.Many changes have reshaped the content, process and concerns of American medical education since Osler''s time. Subspecialization and balkanization of medical education and practice have become dominant. Many of the important issues in medicine today do not fit neatly into the domain of any of the established specialties or medical organizations. There is now an urgent need to promote generalist attitudes in medicine, and the Oslerian tradition has much to offer in approaching today''s problems in medical education and practice.     

Did Osler suffer from "paranoia antitherapeuticum baltimorensis"?: A comparative content analysis of The Principles and Practice of Medicine and Harrison's Principles of Internal Medicine, 11th edition

One of the most important legacies of Sir William Osler was his textbook The Principles and Practice of Medicine. A common criticism of the book when it was first published was its deficiency in the area of therapeutics. In this article, the 1st edition of The Principles and Practice of Medicine is compared with the 11th edition of Harrison''s Principles of Internal Medicine. The analysis focuses on the treatment recommendations for 4 conditions that were covered in both books (diabetes mellitus, ischemic heart disease, pneumonia and typhoid fever). Osler''s textbook dealt with typhoid fever and pneumonia at greater length, whereas Harrison''s placed more emphasis on diabetes mellitus and ischemic heart disease. Notwithstanding Osler''s reputation as a therapeutic nihilist, the 2 books devoted equivalent space to treatment (in terms of proportion of total sentences for the conditions). For all conditions except ischemic heart disease, Osler concentrated on general measures and symptomatic care. Throughout Osler''s textbook numerous negative comments are made about the medicinal treatment of various conditions. A more accurate statement about Osler''s therapeutic approach was that he was a "medicinal nihilist." His demand for proof of efficacy before use of a medication remains relevant.     

Sir William Osler revisited.

The basis of Sir William Osler''s fame is elusive to almost all and the appropriateness of such recognition is questioned by many. His many contributions as a practitioner, teacher, writer, and scientist in medicine do not adequately explain his prominence 60 years following his death. It was his participation in the covenant of medicine and the special components of that relationship that may account for his hold on his followers today.     

Equitable maritime boundary delimitation,as exemplified in the work of the international court of justice during the presidency of sir Robert Yewdall Jennings and Beyond

The article contains a systematic survey of decisions rendered by the International Court of Justice (and its Chamber) under the presidency of Sir Robert Yewdall Jennings in three cases (Guinea Bissau v. Senegal, Gulf of Fonseca, and Denmark v. Norway,) involving equitable maritime delimitation, and in one case (East Timor) settled after Sir Robert's presidency. Distinct features, which are particularly pronounced in the landmark Denmark v. Norway Judgment, are the increased consistency and degree of predictability in the complex process of applying equity in maritime delimitation, of which Sir Robert has been a strong advocate. The important procedural aspects of the case law under Sir Robert's presidency are also analyzed. These are exemplified by the role of the Court as a partner in preventive diplomacy and by the precedential permission granted a third state to intervene as a nonparty. While highlighting the two presently pending cases (Qatar/Bahrain and Cameroon v. Nigeria), the author hopes that these settlements will significantly benefit from substantial and procedural solutions endorsed by the Court during Sir Robert's presidency.     

Darwin on island plants

Islands played a key role in Charles Darwin's observations and experiments on plant dispersal. By means of these experiments, he expunged the old idea that a given species could originate at multiple times and in multiple places. More importantly, by seeing the capabilities for dispersal of plant seeds, fruits and branches, he was able to develop ideas of how plants reach islands and thus he is one of the founders of plant biogeography. For facts regarding floristic distribution of plants, Darwin relied on other workers, most notably Sir Joseph Dalton Hooker. Among his insights were the differences between oceanic and continental islands on a floristic basis, ideas on how age of island and distance from mainland areas influenced composition of island floras, the nature of endemism on islands and the role islands and archipelagos served as stepping stones in dispersal. Ingenious at proposing hypotheses, but always respectful of facts, Darwin sought explanations for plant adaptations on islands at a time when knowledge of island botany was little more than floristic in nature. These explanations are compared with selected recent works in island botany. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161 , 20–25.     

Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle

Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded. Using ‘ancient’ DNA techniques, we quantified variation at 14 autosomal microsatellite loci. Assignment tests showed several museum specimens genetically matched recently field-sampled birds from their island of origin. Some were misclassified or were difficult to classify. Darwin''s exceptionally large ground finches (Geospiza magnirostris) from Floreana and San Cristóbal were genetically distinct from several other currently existing populations. Sharp-beaked ground finches (Geospiza difficilis) from Floreana and Isabela were also genetically distinct. These four populations are currently extinct, yet they were more genetically distinct from congeners than many other species of Darwin''s finches are from each other. We conclude that a significant amount of the finch biodiversity observed and collected by Darwin has been lost since the voyage of the Beagle.     

A c-Myc–SIRT1 feedback loop regulates cell growth and transformation

The protein deacetylase SIRT1 has been implicated in a variety of cellular functions, including development, cellular stress responses, and metabolism. Increasing evidence suggests that similar to its counterpart, Sir2, in yeast, Caenorhabditis elegans, and Drosophila melanogaster, SIRT1 may function to regulate life span in mammals. However, SIRT1''s role in cancer is unclear. During our investigation of SIRT1, we found that c-Myc binds to the SIRT1 promoter and induces SIRT1 expression. However, SIRT1 interacts with and deacetylates c-Myc, resulting in decreased c-Myc stability. As a consequence, c-Myc''s transformational capability is compromised in the presence of SIRT1. Overall, our experiments identify a c-Myc–SIRT1 feedback loop in the regulation of c-Myc activity and cellular transformation, supporting/suggesting a role of SIRT1 in tumor suppression.     

1 July 1858: what Wallace knew; what Lyell thought he knew; what both he and Hooker took on trust; and what Charles Darwin never told them

At the Linnean Society on 1 July 1858, Charles Lyell and Joseph Hooker, using only an extract from Charles Darwin's unpublished essay of 1844, and a copy of a recent letter to Asa Gray in Boston, argued successfully that Darwin understood how species originate long before a letter from Alfred Russel Wallace outlining his own version of the theory of evolution arrived at Darwin's home. That letter from Ternate in the Malay Archipelago, however, was not the first letter Darwin received from Wallace. This article will contend that two of the three letters Wallace sent Darwin between 10 October 1856 and 9 March 1858 arrived much earlier than Darwin recorded, thereby allowing him time to assess Wallace's ideas and claim an independent understanding of how the operation of divergence and extinction in the natural world leads strongly marked varieties to be identified as new species. By the time of the Linnean meeting Darwin's new ideas had filtered into his letters and ‘big’ species book, despite the absence of any independent evidence from the natural world to justify his constant insistence to have been guided only by inductive reasoning. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 725–736.     

Darwin's Galápagos finches in modern biology

One of the classic examples of adaptive radiation under natural selection is the evolution of 15 closely related species of Darwin''s finches (Passeriformes), whose primary diversity lies in the size and shape of their beaks. Since Charles Darwin and other members of the Beagle expedition collected these birds on the Galápagos Islands in 1835 and introduced them to science, they have been the subjects of intense research. Many biology textbooks use Darwin''s finches to illustrate a variety of topics of evolutionary theory, such as speciation, natural selection and niche partitioning. Today, as this Theme Issue illustrates, Darwin''s finches continue to be a very valuable source of biological discovery. Certain advantages of studying this group allow further breakthroughs in our understanding of changes in recent island biodiversity, mechanisms of speciation and hybridization, evolution of cognitive behaviours, principles of beak/jaw biomechanics as well as the underlying developmental genetic mechanisms in generating morphological diversity. Our objective was to bring together some of the key workers in the field of ecology and evolutionary biology who study Darwin''s finches or whose studies were inspired by research on Darwin''s finches. Insights provided by papers collected in this Theme Issue will be of interest to a wide audience.