scholarly journals Power, competition, and the nature of history

Paleobiology ◽  
2019 ◽  
Vol 45 (4) ◽  
pp. 517-530 ◽  
Author(s):  
Geerat J. Vermeij
Keyword(s):  
High Frequency ◽  
Evolutionary History ◽  
Metabolic Evolution ◽  
Competition And Cooperation ◽  
The Past ◽  
Directional Change ◽  
History Of ◽  
Repeated Evolution ◽  
Ecosystem Level

AbstractHistorians have debated whether pathways and events from the past to the present are influenced largely by contingency, the dependence of outcomes on particular prior conditions, or whether there is long-term emergent directional change. Previous arguments for predictability in evolutionary history relied on the high frequency of convergence, but the repeated evolution of widely favored adaptations need not imply long-term directionality. Using evidence from the fossil record and arguments concerning the metabolic evolution of organisms, I show here that power (total energy taken up and expended per unit time) has increased stepwise over time at ecosystem-level and global scales thanks to the ratchet-like, cumulative effects of competition and cooperation and to the disproportionate influence of powerful top competitors and opportunistic species on emergent ecosystem properties and processes. The history of life therefore exhibits emergent directionality at large ecosystem-wide scales toward greater power.

Plio-Pleistocene decline of African megaherbivores: No evidence for ancient hominin impacts

Science ◽  
2018 ◽  
Vol 362 (6417) ◽  
pp. 938-941 ◽  
Author(s):  
J. Tyler Faith ◽  
John Rowan ◽  
Andrew Du ◽  
Paul L. Koch
Keyword(s):  
Evolutionary History ◽  
Homo Sapiens ◽  
Top Down ◽  
Large Mammal ◽  
Meat Eating ◽  
The Past ◽  
History Of ◽  
Mammal Communities ◽  
Herbivore Communities

It has long been proposed that pre-modern hominin impacts drove extinctions and shaped the evolutionary history of Africa’s exceptionally diverse large mammal communities, but this hypothesis has yet to be rigorously tested. We analyzed eastern African herbivore communities spanning the past 7 million years—encompassing the entirety of hominin evolutionary history—to test the hypothesis that top-down impacts of tool-bearing, meat-eating hominins contributed to the demise of megaherbivores prior to the emergence ofHomo sapiens. We document a steady, long-term decline of megaherbivores beginning ~4.6 million years ago, long before the appearance of hominin species capable of exerting top-down control of large mammal communities and predating evidence for hominin interactions with megaherbivore prey. Expansion of C4grasslands can account for the loss of megaherbivore diversity.

scholarly journals Extensive introgression and mosaic genomes of Mediterranean endemic lizards

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Weizhao Yang ◽  
Nathalie Feiner ◽  
Catarina Pinho ◽  
Geoffrey M. While ◽  
Antigoni Kaliontzopoulou ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Mediterranean Islands ◽  
The Past ◽  
Island Endemics ◽  
Extant Species ◽  
Mediterranean Island ◽  
History Of ◽  
Entire History ◽  
The Mediterranean ◽  
The Mediterranean Basin

AbstractThe Mediterranean basin is a hotspot of biodiversity, fuelled by climatic oscillation and geological change over the past 20 million years. Wall lizards of the genus Podarcis are among the most abundant, diverse, and conspicuous Mediterranean fauna. Here, we unravel the remarkably entangled evolutionary history of wall lizards by sequencing genomes of 34 major lineages covering 26 species. We demonstrate an early (>11 MYA) separation into two clades centred on the Iberian and Balkan Peninsulas, and two clades of Mediterranean island endemics. Diversification within these clades was pronounced between 6.5–4.0 MYA, a period spanning the Messinian Salinity Crisis, during which the Mediterranean Sea nearly dried up before rapidly refilling. However, genetic exchange between lineages has been a pervasive feature throughout the entire history of wall lizards. This has resulted in a highly reticulated pattern of evolution across the group, characterised by mosaic genomes with major contributions from two or more parental taxa. These hybrid lineages gave rise to several of the extant species that are endemic to Mediterranean islands. The mosaic genomes of island endemics may have promoted their extraordinary adaptability and striking diversity in body size, shape and colouration, which have puzzled biologists for centuries.

How the Desert got a Past: A History of Quaternary Research in Australia’s Deserts

2014 ◽  
Vol 25 (2) ◽  
pp. 172 ◽  
Author(s):  
Mike Smith
Keyword(s):  
Climate Changes ◽  
Conceptual Space ◽  
The Past ◽  
History Of ◽  
The 1960S

This paper examines how the past of desert landscapes has been interpreted since European explorers and scientists first encountered them. It charts the research that created the conceptual space within which archaeologists and Quaternarists now work. Studies from the 1840s–1960s created the notion of a ‘Great Australian Arid Period'. The 1960s studies of Lake Mungo and the Willandra Lakes by Jim Bowler revealed the cyclical nature of palaeolakes, that changed with climate changes in the Pleistocene, and the complexity of desert pasts. SLEADS and other researchers in the 1980s used thermoluminescence techniques that showed further complexities in desert lands beyond the Willandra particularly through new studies in the Strzelecki and Simpson Dunefields, Lake Eyre, Lake Woods and Lake Gregory. Australian deserts are varied and have very different histories. Far from ‘timeless lands', they have carried detailed information about long-term climate changes on continental scales.

scholarly journals Superior Oblique Myokymia Presumed Due to Large Posterior Fossa Arteriovenous Malformation

2020 ◽  
Vol 47 (6) ◽  
pp. 824-825
Author(s):  
Laura Donaldson ◽  
Brian van Adel ◽  
Amadeo R. Rodriguez
Keyword(s):  
High Frequency ◽  
Previous History ◽  
Ocular Motility ◽  
Slit Lamp ◽  
Primary Position ◽  
The Past ◽  
History Of ◽  
Supplementary Material ◽  
The Brain ◽  
Superior Oblique

A 26-year-old female presented with a complaint of intermittent oscillopsia and binocular vertical diplopia for the past 5 years. Over the past several months, she had noticed intermittent pulsatile tinnitus. She was otherwise healthy with no previous history of trauma and had no other visual or neurologic complaints. In Neuro-ophthalmology clinic, she was found to have 20/15 vision in both eyes with full ocular motility. There was a small exophoria in primary position and small esophoria in downgaze. Her slit lamp and fundus examinations were normal. During the assessment, the left eye was noted to undergo high-frequency, small amplitude incyclotorsional oscillations for a few seconds at a time (Video 1 in the supplementary material), which she was able to provoke by looking down. The diagnosis of superior oblique myokymia was made, and an MRI/MRA of the brain was requested.

scholarly journals A case-report of widespread pulmonary embolism in a middle-aged male seven weeks after asymptomatic suspected COVID 19 infection

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Mats Beckman ◽  
Sven Nyrén ◽  
Anna Kistner
Keyword(s):  
Pulmonary Embolism ◽  
High Frequency ◽  
Laboratory Testing ◽  
Troponin T ◽  
Case Presentation ◽  
Contrast Angiography ◽  
History Of ◽  
Exercise Induced ◽  
Significant Disease

Abstract Background Pulmonary embolism (PE) is seen in high frequency in hospital-treated patients with Covid-19. We present a case of suspected Covid-19 with long-term dyspnea and widespread PE. Case presentation A 51- year old male, with no prior medical history, no medication, and non-smoker arrived at the emergency department with exercise induced dyspnea during 4–5 weeks and for the last 48 h dyspnea at rest. Seven weeks before hospitalization, he felt difficulties taking deep breaths for some days but no other symptoms. Oxygen saturation at rest was 93%. Troponin T was 1200 mg/L (ref < 15 mg/L). CT angiography revealed widespread bilateral segmental pulmonary embolism. Additional findings were ground glass opacities that could match Covid-19. The patient tested negative for SARS -CoV-2. Full dose tinzaparin was given for 2 days in hospital, followed by apixaban for 6 months. Recovery has been uneventful so far. Conclusions Long-term breathing difficulties might be relatively common after non-hospitalized symptomatic Covid-19. The frequency of PE in this group is unknown. We report a case of suspected covid-19 with widespread PE and a long history of dyspnea but no other symptoms. In our case slight hypoxia and laboratory testing indicated significant disease, which was proven with contrast angiography. This case shows that PE is a differential diagnosis in non-hospitalized symptomatic Covid-19 with persisting breathing problems.

scholarly journals Mnemonic Populism: The Polish Holocaust Law and its Afterlife

2020 ◽  
pp. 1-13 ◽  
Author(s):  
Kornelia Kończal
Keyword(s):  
Significant Other ◽  
The Past ◽  
Cultural Foundations ◽  
The Holocaust ◽  
Heated Debate ◽  
History Of ◽  
The Law ◽  
The Relationship

In early 2018, the Polish parliament adopted controversial legislation criminalising assertions regarding the complicity of the ‘Polish Nation’ and the ‘Polish State’ in the Holocaust. The so-called Polish Holocaust Law provoked not only a heated debate in Poland, but also serious international tensions. As a result, it was amended only five months after its adoption. The reason why it is worth taking a closer look at the socio-cultural foundations and political functions of the short-lived legislation is twofold. Empirically, the short history of the Law reveals a great deal about the long-term role of Jews in the Polish collective memory as an unmatched Significant Other. Conceptually, the short life of the Law, along with its afterlife, helps capture poll-driven, manifestly moralistic and anti-pluralist imaginings of the past, which I refer to as ‘mnemonic populism’. By exploring the relationship between popular and political images of the past in contemporary Poland, this article argues for joining memory and populism studies in order to better understand what can happen to history in illiberal surroundings.

scholarly journals Optimal position of a long-term central venous catheter tip in a pediatric patient with congenital diseases

2012 ◽  
Vol 4 (3) ◽  
pp. 32 ◽  
Author(s):  
Marco Caruselli ◽  
Dario Galante ◽  
Anna Ficcadenti ◽  
Laura Carboni ◽  
Federica Franco ◽  
...  
Keyword(s):  
Central Venous Catheter ◽  
High Frequency ◽  
Young Patients ◽  
Venous Catheter ◽  
Central Venous ◽  
Optimal Position ◽  
Congenital Diseases ◽  
The Past ◽  
Catheter Tip

Progress in medical and scientific research has increased the chances of survival for young patients with congenital diseases, children who, in the past, would not have had any chance of survival. Nowadays, congenital diseases can be treated with appropriate replacement therapies. These treatments can be difficult to administer in young patients because of the high frequency of administration (sometimes more than a dose per week), the use of intravenous infusion and the long-term or life-term requirement.

To Utopia and Back: A Cycle in the History of the Chinese Communist Party

1981 ◽  
Vol 87 ◽  
pp. 407-439 ◽  
Author(s):  
Stuart R. Schram
Keyword(s):  
Communist Party ◽  
Chinese Communist Party ◽  
The Past ◽  
Look Back ◽  
The Future ◽  
History Of ◽  
The Chinese Communist Party ◽  
Sixtieth Anniversary

On 1 July 1981 the Chinese Communist Party celebrated the sixtieth anniversary of its foundation. To mark this occasion, the Party itself issued a statement summing up the experience of recent decades. It seems an appropriate time for outsiders as well to look back over the history of the past 60 years, in the hope of grasping long-term tendencies which may continue to influence events in the future.

scholarly journals The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: the youngest record of Presbyornithidae

2016 ◽  
Vol 3 (2) ◽  
pp. 150635 ◽  
Author(s):  
Vanesa L. De Pietri ◽  
R. Paul Scofield ◽  
Nikita Zelenkov ◽  
Walter E. Boles ◽  
Trevor H. Worthy
Keyword(s):  
Evolutionary History ◽  
South Australia ◽  
First Record ◽  
South American ◽  
Crown Group ◽  
Term Survival ◽  
Skeletal Morphology ◽  
Ancient Lineage ◽  
History Of

Presbyornithids were the dominant birds in Palaeogene lacustrine assemblages, especially in the Northern Hemisphere, but are thought to have disappeared worldwide by the mid-Eocene. Now classified within Anseriformes (screamers, ducks, swans and geese), their relationships have long been obscured by their strange wader-like skeletal morphology. Reassessment of the late Oligocene South Australian material attributed to Wilaru tedfordi , long considered to be of a stone-curlew (Burhinidae, Charadriiformes), reveals that this taxon represents the first record of a presbyornithid in Australia. We also describe the larger Wilaru prideauxi sp. nov. from the early Miocene of South Australia, showing that presbyornithids survived in Australia at least until ca 22 Ma. Unlike on other continents, where presbyornithids were replaced by aquatic crown-group anatids (ducks, swans and geese), species of Wilaru lived alongside these waterfowl in Australia. The morphology of the tarsometatarsus of these species indicates that, contrary to other presbyornithids, they were predominantly terrestrial birds, which probably contributed to their long-term survival in Australia. The morphological similarity between species of Wilaru and the Eocene South American presbyornithid Telmabates antiquus supports our hypothesis of a Gondwanan radiation during the evolutionary history of the Presbyornithidae. Teviornis gobiensis from the Late Cretaceous of Mongolia is here also reassessed and confirmed as a presbyornithid. These findings underscore the temporal continuance of Australia’s vertebrates and provide a new context in which the phylogeny and evolutionary history of presbyornithids can be examined.

Resilience of plant and testate amoeba communities after climatic and anthropogenic disturbances in a Baltic bog in Northern Poland: Implications for ecological restoration

The Holocene ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 130-141 ◽  
Author(s):  
Mariusz Gałka ◽  
Kazimierz Tobolski ◽  
Aleksandra Górska ◽  
Mariusz Lamentowicz
Keyword(s):  
Human Impacts ◽  
Testate Amoebae ◽  
Ice Age ◽  
Testate Amoeba ◽  
Raised Bogs ◽  
The Past ◽  
Ombrotrophic Peatland ◽  
History Of ◽  
Climate Cooling

This study explores the history of the development of Sphagnum communities in an ombrotrophic peatland – Bagno Kusowo – over the past 650 years, based on high-resolution plant macrofossil and testate amoebae analysis. Our research provided information related to the length of peatland existence and the characteristics of its natural/pristine state before the most recent human impacts. Changes in the Sphagnum communities before human impact could have resulted from climate cooling during the ‘Little Ice Age’ (LIA). In this cold and unstable hydrological period, among vascular plants, Eriophorum vaginatum and Baeothryon caespitosum dominated in the peatland vegetation. Peat-forming Sphagnum communities survived the drainage conducted during the 20th century at the Bagno Kusowo bog. We provide three important messages through this study: (1) testate amoebae reflect similar hydrological trends in two peat cores despite considerable microhabitat variability, (2) average long-term water level 10 cm below the surface should be a target for active bog conservation and (3) sites like Bagno Kusowo are extremely important to preserve the remains of pristine biodiversity (including genetic diversity of plants and protists) that was completely removed from most of the raised bogs in Europe due to human activities, for example, drainage.

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