The Reception and Acceptance of Continental Drift Theory as a Rational Episode in the History of Science

2019 ◽  
pp. 51-89
Author(s):  
Henry Frankel
Keyword(s):  
History Of Science ◽  
Continental Drift ◽  
Drift Theory ◽  
History Of

scholarly journals Speciation rates of subviral pathogens of angiosperms abruptly decreased at the Cretaceous–Paleogene boundary

2019 ◽  
Author(s):  
Piotr Bajdek
Keyword(s):  
Mass Extinction ◽  
Continental Drift ◽  
Time Calibration ◽  
Drift Theory ◽  
Speciation Rates ◽  
History Of ◽  
Probable Impact ◽  
Mass Extinction Event ◽  
Extinction Events ◽  
First Time

Biogeographic distribution of infected plants and the continental drift theory allow a time calibration of the phylogenetic tree of Pospiviroidae. Viroids evolved in the late Early Cretaceous shortly after the appearance of angiosperms, which constitute their only known hosts. No decline in the estimated speciation rates of Pospiviroidae is observed during the Late Cretaceous but they abruptly decreased at the Cretaceous–Paleogene boundary. However, an adaptive radiation of Pospiviroidae which occurred in the late Paleocene may reflect a recovery from the K–Pg mass extinction. The evolutionary history of viroids has been in part shaped by radiation and extinction events of angiosperms. Herein, for the first time I show the probable impact of a mass extinction event on the speciation rates of subviral pathogens, which are the simplest known lifeforms.

scholarly journals Os valores geoéticos e a relutância na consideração de novas ideias: o caso da Deriva Continental de Wegener

2019 ◽  
Vol 20 ◽  
pp. 685-694
Author(s):  
Alexandra Cardoso
Keyword(s):  
Eighteenth Century ◽  
History Of Science ◽  
Continental Drift ◽  
Scientific Development ◽  
Educational Resource ◽  
Keywords History Of Science ◽  
History Of ◽  
Integral Development ◽  
Explanatory Mechanism ◽  
Case Based

Resumo A Deriva Continental de Wegener surge num período em que o imobilismo e o contracionismo geológicos eram as ideias maioritariamente aceites no que diz respeito à interpretação da história da Terra. A hipótese de Wegener, contrária às referidas teorias, desencadeou uma das maiores controvérsias da história das geociências. Na primeira metade do século XVIII, a falta de um mecanismo explicativo dos movimentos horizontais da crusta foi a crítica mais recorrente ao seu trabalho. No entanto, tal não justifica totalmente a desconsideração da hipótese de Wegener pela maior parte da comunidade científica da época. Ideias inovadoras e revolucionárias, como as que caracterizam a Deriva Continental, são, geralmente, acompanhadas de reações de preconceito e rejeição. Estas reações, documentadas diversas vezes ao longo da história da ciência, afiguram-se como barreiras difíceis de ultrapassar, afetando o desenvolvimento científico. Atualmente, encontram-se em estudo uma série de valores geoéticos que deverão pautar a conduta dos geocientistas no exercício da sua profissão e que incluem a compreensão e respeito pelas diferentes ideias dos pares. No presente trabalho, desenvolveu-se um recurso educativo, segundo a metodologia de ensino baseado em casos, com a pretensão de contribuir para a compreensão do caráter provisório da ciência e para a consciencialização acerca dos valores geoéticos que devem estar na base de um íntegro desenvolvimento das geociências. Palavras-chave: história da ciência; geoética; ensino baseado em casos. Abstract Wegener's Continental Drift arises at a time when geological immobilism and contractionism were the most widely accepted ideas regarding the interpretation of Earth's history. Wegener's hypothesis, contrary to these theories, unleashed one of the biggest controversies in the history of geosciences. In the first half of the eighteenth century, the lack of an explanatory mechanism for the horizontal movements of the crust was the most recurrent criticism concerning his work. However, this does not fully justify the disregard of Wegener's hypothesis by most of the scientific community at the time. Innovative and revolutionary ideas, such as those that characterize the Continental Drift, are usually accompanied by reactions of prejudice and rejection. These reactions, documented several times throughout the history of science, appear as barriers that are difficult to overcome, affecting scientific development. Currently, several geoethical values that should guide the conduct of the geoscientists in the exercise of their profession are being studied and they include the understanding and respect for the different ideas of others. In the present work, an educational resource has been developed, according to the methodology of case-based teaching, with the aim of contributing to the understanding of the provisional nature of science and to the awareness of the geoethical values that must be the basis of an integral development of geosciences. Keywords: history of science; geoethics; case-based teaching

scholarly journals Divergence rates of subviral pathogens of angiosperms abruptly decreased at the Cretaceous-Paleogene boundary

2019 ◽  
Vol 4 ◽  
pp. 89-101 ◽  
Author(s):  
Piotr Bajdek
Keyword(s):  
Mass Extinction ◽  
Continental Drift ◽  
Time Calibration ◽  
Extinction Event ◽  
Drift Theory ◽  
History Of ◽  
Probable Impact ◽  
Mass Extinction Event ◽  
Extinction Events ◽  
First Time

Biogeographic distribution of infected plants and the continental drift theory allow a tentative time calibration of the phylogenetic tree of Pospiviroidae. Hypothetically, viroids evolved in the late Early Cretaceous shortly after the appearance of angiosperms, which constitute their only known hosts. No decline in the estimated divergence rates of Pospiviroidae is observed during the Late Cretaceous but it appears that they abruptly decreased at the Cretaceous-Paleogene boundary. However, an adaptive radiation of Pospiviroidae which occurred in the late Paleocene may reflect a recovery from the Cretaceous-Paleogene (K–Pg) mass extinction. It seems that the evolutionary history of viroids has been in part shaped by radiation and extinction events of angiosperms. Herein, for the first time I show the probable impact of a mass extinction event on the divergence rates of subviral pathogens, which are the simplest known “lifeforms”.

scholarly journals Speciation rates of subviral pathogens of angiosperms abruptly decreased at the Cretaceous–Paleogene boundary

2019 ◽  
Author(s):  
Piotr Bajdek
Keyword(s):  
Mass Extinction ◽  
Continental Drift ◽  
Time Calibration ◽  
Drift Theory ◽  
Speciation Rates ◽  
History Of ◽  
Probable Impact ◽  
Mass Extinction Event ◽  
Extinction Events ◽  
First Time

Biogeographic distribution of infected plants and the continental drift theory allow a time calibration of the phylogenetic tree of Pospiviroidae. Viroids evolved in the late Early Cretaceous shortly after the appearance of angiosperms, which constitute their only known hosts. No decline in the estimated speciation rates of Pospiviroidae is observed during the Late Cretaceous but they abruptly decreased at the Cretaceous–Paleogene boundary. However, an adaptive radiation of Pospiviroidae which occurred in the late Paleocene may reflect a recovery from the K–Pg mass extinction. The evolutionary history of viroids has been in part shaped by radiation and extinction events of angiosperms. Herein, for the first time I show the probable impact of a mass extinction event on the speciation rates of subviral pathogens, which are the simplest known lifeforms.

Piaget and Garcia's History of Science

1990 ◽  
Vol 35 (7) ◽  
pp. 654-656
Author(s):  
Harry Beilin
Keyword(s):  
History Of Science ◽  
History Of
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