scholarly journals Explaining the ocean's richest biodiversity hotspot and global patterns of fish diversity

2018 ◽  
Vol 285 (1888) ◽  
pp. 20181314 ◽  
Author(s):  
Elizabeth Christina Miller ◽  
Kenji T. Hayashi ◽  
Dongyuan Song ◽  
John J. Wiens
Keyword(s):  
Large Scale ◽  
Fish Diversity ◽  
Relative Importance ◽  
Diversification Rates ◽  
Marine Habitats ◽  
History Of ◽  
Richness Patterns ◽  
Colonization Time ◽  
Almost All

For most marine organisms, species richness peaks in the Central Indo-Pacific region and declines longitudinally, a striking pattern that remains poorly understood. Here, we used phylogenetic approaches to address the causes of richness patterns among global marine regions, comparing the relative importance of colonization time, number of colonization events, and diversification rates (speciation minus extinction). We estimated regional richness using distributional data for almost all percomorph fishes (17 435 species total, including approximately 72% of all marine fishes and approximately 33% of all freshwater fishes). The high diversity of the Central Indo-Pacific was explained by its colonization by many lineages 5.3–34 million years ago. These relatively old colonizations allowed more time for richness to build up through in situ diversification compared to other warm-marine regions. Surprisingly, diversification rates were decoupled from marine richness patterns, with clades in low-richness cold-marine habitats having the highest rates. Unlike marine richness, freshwater diversity was largely derived from a few ancient colonizations, coupled with high diversification rates. Our results are congruent with the geological history of the marine tropics, and thus may apply to many other organisms. Beyond marine biogeography, we add to the growing number of cases where colonization and time-for-speciation explain large-scale richness patterns instead of diversification rates.

scholarly journals Explaining large-scale patterns of vertebrate diversity

2015 ◽  
Vol 11 (7) ◽  
pp. 20150506 ◽  
Author(s):  
John J. Wiens
Keyword(s):  
Species Richness ◽  
Large Scale ◽  
Comparative Methods ◽  
Phylogenetic Comparative Methods ◽  
Metabolic Rates ◽  
Diversification Rates ◽  
Richness Patterns ◽  
Current Species

The major clades of vertebrates differ dramatically in their current species richness, from 2 to more than 32 000 species each, but the causes of this variation remain poorly understood. For example, a previous study noted that vertebrate clades differ in their diversification rates, but did not explain why they differ. Using a time-calibrated phylogeny and phylogenetic comparative methods, I show that most variation in diversification rates among 12 major vertebrate clades has a simple ecological explanation: predominantly terrestrial clades (i.e. birds, mammals, and lizards and snakes) have higher net diversification rates than predominantly aquatic clades (i.e. amphibians, crocodilians, turtles and all fish clades). These differences in diversification rates are then strongly related to patterns of species richness. Habitat may be more important than other potential explanations for richness patterns in vertebrates (such as climate and metabolic rates) and may also help explain patterns of species richness in many other groups of organisms.

scholarly journals Why are there so few fish in the sea?

2012 ◽  
Vol 279 (1737) ◽  
pp. 2323-2329 ◽  
Author(s):  
Greta Carrete Vega ◽  
John J. Wiens
Keyword(s):  
Fish Species ◽  
Large Scale ◽  
Marine Environments ◽  
Diversification Rates ◽  
Marine Habitats ◽  
Low Diversity ◽  
Terrestrial Environments ◽  
Global Biodiversity ◽  
Marine Vertebrates ◽  
Area And Volume

The most dramatic gradient in global biodiversity is between marine and terrestrial environments. Terrestrial environments contain approximately 75–85% of all estimated species, but occupy only 30 per cent of the Earth's surface (and only approx. 1–10% by volume), whereas marine environments occupy a larger area and volume, but have a smaller fraction of Earth's estimated diversity. Many hypotheses have been proposed to explain this disparity, but there have been few large-scale quantitative tests. Here, we analyse patterns of diversity in actinopterygian (ray-finned) fishes, the most species-rich clade of marine vertebrates, containing 96 per cent of fish species. Despite the much greater area and productivity of marine environments, actinopterygian richness is similar in freshwater and marine habitats (15 150 versus 14 740 species). Net diversification rates (speciation–extinction) are similar in predominantly freshwater and saltwater clades. Both habitats are dominated by two hyperdiverse but relatively recent clades (Ostariophysi and Percomorpha). Remarkably, trait reconstructions (for both living and fossil taxa) suggest that all extant marine actinopterygians were derived from a freshwater ancestor, indicating a role for ancient extinction in explaining low marine richness. Finally, by analysing an entirely aquatic group, we are able to better sort among potential hypotheses for explaining the paradoxically low diversity of marine environments.

scholarly journals ENDOCRINE HISTORY: The history of discovery, synthesis and development of testosterone for clinical use

2019 ◽  
Vol 180 (6) ◽  
pp. R201-R212 ◽  
Author(s):  
Eberhard Nieschlag ◽  
Susan Nieschlag
Keyword(s):  
Large Scale ◽  
Biological Effects ◽  
Active Agent ◽  
Serum Levels ◽  
Clinical Use ◽  
Practical Applications ◽  
Physiological Serum ◽  
History Of ◽  
Almost All ◽  
Male Hormone

As the most important male hormone, testosterone has an impact on almost all organs and body functions. The biological effects of testosterone and the testes have been known since antiquity, long before testosterone was identified as the active agent. Practical applications of this knowledge were castration of males to produce obedient servants, for punishment, for preservation of the prepubertal soprano voice and even for treatment of diseases. Testes were used in organotherapy and transplanted as treatment for symptoms of hypogonadism on a large scale, although these practices had only placebo effects. In reaction to such malpractice in the first half of the 20th century science and the young pharmaceutical industry initiated the search for the male hormone. After several detours together with their teams in 1935, Ernst Laqueur (Amsterdam) isolated and Adolf Butenandt (Gdansk) as well as Leopold Ruzicka (Zürich) synthesized testosterone. Since then testosterone has been available for clinical use. However, when given orally, testosterone is inactivated in the liver, so that parenteral forms of administration or modifications of the molecule had to be found. Over 85 years the testosterone preparations have been slowly improved so that now physiological serum levels can be achieved.

scholarly journals Molecular anatomy of the pre-primitive-streak chick embryo

Open Biology ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 190299 ◽  
Author(s):  
Hyung Chul Lee ◽  
Hui-Chun Lu ◽  
Mark Turmaine ◽  
Nidia M. M. Oliveira ◽  
Youwen Yang ◽  
...  
Keyword(s):  
Chick Embryo ◽  
Cell Polarity ◽  
Large Scale ◽  
Functional Anatomy ◽  
Primitive Streak ◽  
Vertebrate Species ◽  
History Of ◽  
Molecular Anatomy ◽  
Evolutionary Comparisons

The early stages of development of the chick embryo, leading to primitive streak formation (the start of gastrulation), have received renewed attention recently, especially for studies of the mechanisms of large-scale cell movements and those that position the primitive streak in the radial blastodisc. Over the long history of chick embryology, the terminology used to define different regions has been changing, making it difficult to relate studies to each other. To resolve this objectively requires precise definitions of the regions based on anatomical and functional criteria, along with a systematic molecular map that can be compared directly to the functional anatomy. Here, we undertake these tasks. We describe the characteristic cell morphologies (using scanning electron microscopy and immunocytochemistry for cell polarity markers) in different regions and at successive stages. RNAseq was performed for 12 regions of the blastodisc, from which a set of putative regional markers was selected. These were studied in detail by in situ hybridization. Together this provides a comprehensive resource allowing the community to define the regions unambiguously and objectively. In addition to helping with future experimental design and interpretation, this resource will also be useful for evolutionary comparisons between different vertebrate species.

scholarly journals Transient T-bet expression functionally specifies a distinct T follicular helper subset

2018 ◽  
Vol 215 (11) ◽  
pp. 2705-2714 ◽  
Author(s):  
Difeng Fang ◽  
Kairong Cui ◽  
Kairui Mao ◽  
Gangqing Hu ◽  
Rao Li ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Cell Subset ◽  
Tissue Imaging ◽  
Mouse Strains ◽  
Tfh Cells ◽  
Follicular Helper ◽  
History Of ◽  
Ifn Γ ◽  
Almost All

T follicular helper (Tfh) cells express transcription factor BCL-6 and cytokine IL-21. Mature Tfh cells are also capable of producing IFN-γ without expressing the Th1 transcription factor T-bet. Whether this IFN-γ–producing Tfh population represents a unique Tfh subset with a distinct differentiation pathway is poorly understood. By using T-bet fate–mapping mouse strains, we discovered that almost all the IFN-γ–producing Tfh cells have previously expressed T-bet and express high levels of NKG2D. DNase I hypersensitivity analysis indicated that the Ifng gene locus is partially accessible in this “ex–T-bet” population with a history of T-bet expression. Furthermore, multicolor tissue imaging revealed that the ex–T-bet Tfh cells found in germinal centers express IFN-γ in situ. Finally, we found that IFN-γ–expressing Tfh cells are absent in T-bet–deficient mice, but fully present in mice with T-bet deletion at late stages of T cell differentiation. Together, our findings demonstrate that transient expression of T-bet epigenetically imprints the Ifng locus for cytokine production in this Th1-like Tfh cell subset.

scholarly journals N. E. Soum – the First Head of the Museum Department of the Institute of Out-of-School Education in Petrograd

2020 ◽  
pp. 1228-1240
Author(s):  
Vitaly G. Ananiev ◽  
Keyword(s):  
Large Scale ◽  
Structural Changes ◽  
School Education ◽  
Point Of View ◽  
Professional Activities ◽  
The Enlightenment ◽  
History Of ◽  
Almost All ◽  
Revolutionary Period ◽  
Out Of School

The revolutions of 1917 prompted a large-scale reorganization of almost all aspects of life in Russia. An important actor in its implementation was intelligentsia. Studying the biographies of the participants in that processes is important for two reasons. Firstly, it allows us to fill the gaps in the history of certain phenomena (i.e., the history of museum education in Russia). Secondly, it’s important from the point of view of prosopography, as biographies help a better understanding of certain historical types. That is important in the context of the anthropological approach to the study of revolutionary events. The object of this article is the biography of one of the personalities of the first post-revolutionary years, Nikolai Emmanuilovich Soum (1879–1926). Studying chemistry at St. Petersburg University in the 1890s–1900s, Soum to a great extent followed the path laid by his father's professional activities. However, he didn’t succeed in accomplishing his studies, perhaps on the account of his father’s death and failed family finances. In the 1910s, when working as a chemist, he joined in the activities of scientific and educational societies. The enlightenment pathos and practical application of science (his interest in photography) prepared the changes, which took place immediately after the revolution. Since 1918 Soum served in the Petrograd gubernia department of public education, and from 1919 headed the Museum department of the Petrograd Institute of Out-of-School Education. One of his first projects was system of training of museum workers, one of the first in Russia. Structural changes and unfavorable political conditions hindered the implementation of the initiative. Soum, same as earlier in the pre-revolutionary period, was pushed to the periphery of cultural life.

scholarly journals BIOPREPARATIONS FOR THE PRODUCTION OF ENVIRONMENTALLY SAFE FOOD – Part I

2017 ◽  
pp. 63-69
Author(s):  
Tatiana Nugmanova
Keyword(s):  
Large Scale ◽  
Weather Conditions ◽  
Scale Production ◽  
Large Scale Production ◽  
Adverse Weather ◽  
Environmentally Safe ◽  
History Of ◽  
Safe Food ◽  
Almost All ◽  
The Cost

Russian biopreparations cover almost all aspects of the problem of growing plants. The history of development and implementation of industrial large-scale production of biopreparations in Russia goes back more than 40 years. Biopreparations have a purposeful action and are divided into the following main types: bioinsecticides, biofungicides, biofertilizers, immunomodulators and regulators of plant growth and development, as well as land-fertilizing biopreparations. The variety of Russian biopreparations can fully ensure the implementation of the potential varietal properties of agricultural plants, minimize damage from adverse weather conditions, reduce the cost of chemicals, restore soil humus and obtain environmentally friendly food.

scholarly journals Topical issues of dissertations’ references on architecture as an information resource to support research in architectural science

Bibliosphere ◽  
2017 ◽  
pp. 85-90
Author(s):  
I. I. Komarova ◽  
A. L. Tretyakov
Keyword(s):  
Information Needs ◽  
Large Scale ◽  
Subject Area ◽  
Human Knowledge ◽  
History Of ◽  
The Subject ◽  
Almost All ◽  
Architectural Research ◽  
Architectural Knowledge ◽  
Support Research

Studying the architectural science bibliography has shown that during 150 years of its history few indices have been created, and recent decades almost all architectural bibliography has not gone beyond the framework of the nation-wide index «Chronicles of Book Chamber». This article examines the fundamental nature of bibliographic science for purposes of architectural research. The article objective is determining ways of architectural bibliography development and generating a unified database of architectural knowledge in the context of contemporary socio-economic and socio-cultural realities. It considers defended dissertations on specialty «Architecture»; describes information resources containing in their thesis structure on the subject area. Attention is focused on the distribution of defended dissertations by years, cities and thematic nests. The paper has revealed thesis devoted to the theory and history of foreign architecture. It emphasizes the need of further large-scale research with an analysis of the entire spectrum of human knowledge, which includes dissertations related to architectural science. The authors conclude: 1. There is no complete systematically presented unified catalog of dissertations on architecture, including resources of the Russian Book Chamber. 2. It is necessary to create such resource, which would satisfy the information needs of different groups of users.

Ice-Sheet Dynamics and Glacial History of Southeasternmost Baffin Island and Outermost Hudson Strait

1988 ◽  
Vol 30 (2) ◽  
pp. 116-136 ◽  
Author(s):  
Gifford H. Miller ◽  
Paul J. Hearty ◽  
Jay A. Stravers
Keyword(s):  
Large Scale ◽  
Late Quaternary ◽  
Hudson Bay ◽  
Baffin Island ◽  
Ice Flow ◽  
Radiocarbon Dates ◽  
The Matrix ◽  
History Of ◽  
Ice Sheet Dynamics

Southeasternmost Baffin Island is mantled by Hudson Strait drift; it contains abundant limestone erratics and 20 to 50% carbonate in the matrix. To the northwest, it is replaced by drift dominated by locally derived rock of the Canadian Shield. The sense and orientation of ice-erosional features demonstrate that Hudson Strait drift is associated with northeasterly ice flow that crossed the tip of Meta Incognita Peninsula; local drift, associated with ice flow S10°W along the Hudson Strait coast, was derived from a dispersal center on the peninsula. Erratic lithologies contained in the Hudson Strait drift indicate a Labradorean provenance. Large-scale bedrock molding and the distribution of cirques indicate NE-flowing ice has been dominant throughout the middle and late Quaternary. Radiocarbon dates of in situ shells confirm that deglaciation began more than 11,000 yr ago, with the Frobisher Bay coast becoming ice free by 9300 yr ago. Five dates from Hudson Strait suggest that the strait was deglaciated before 9000 yr BP. However, ice from the Labradorean Sector recrossed Hudson Strait during the Cockburn Substage, about 8500 yr ago, damming drainage from the west. Final retreat of Labradorean ice from Baffin Island was complete by 8000 yr ago, at which time the sea was able to penetrate Hudson Bay.

Materials for the history of the gospel-Baptist movement in Ukraine

1996 ◽  
pp. 4-15
Author(s):  
S. Golovaschenko ◽  
Petro Kosuha
Keyword(s):  
Large Scale ◽  
Religious Studies ◽  
Theological Seminary ◽  
National Academy Of Sciences ◽  
Evangelical Christians ◽  
Evangelical Christian ◽  
First Results ◽  
History Of ◽  
Fruitful Cooperation ◽  
Academy Of Sciences

The report is based on the first results of the study "The History of the Evangelical Christians-Baptists in Ukraine", carried out in 1994-1996 by the joint efforts of the Department of Religious Studies at the Institute of Philosophy of the National Academy of Sciences of Ukraine and the Odessa Theological Seminary of Evangelical Christian Baptists. A large-scale description and research of archival sources on the history of evangelical movements in our country gave the first experience of fruitful cooperation between secular and church researchers.

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