Textbooks teach the principles of science. Lyellʼs geology textbooks emphasized vertical crustal movement. He avoided far-fetched continental-drift hypotheses by Hopkins in 1844 and Pepper in 1861. Their notions of drift were supported by fossil and paleoclimate evidence, but their causes were global magnetism and electrochemical crystallization and dissolution. Danaʼs textbooks from 1863 to 1895 taught that the symmetry of North America proved it had always stood alone; thus Americans were conditioned to reject Wegenerʼs concept of a Carboniferous supercontinent. Unaware of Wegenerʼs hypothesis in 1912, Schuchert launched a textbook series that guided American geological opinion from 1915 to the 1960s. His paleogeographic models required Carboniferous land bridges to connect fixed continents. He and coauthors Longwell and Dunbar eventually realized that Wegenerʼs continental-drift hypothesis would disprove land-bridge theory and solve problems of mountain ranges, paleoclimates, and fossil distributions, but they guarded against it in their textbooks. Already in 1927, Holmes proposed that convection with sea-floor spreading drove continental drift, but editor Schuchert would not publish that breakthrough. Geologists Du Toit, Van der Gracht, Holmes, Shand, Bailey, and Grabau showed the merits of continental drift, but their publications had little impact. Willis accepted the invitations of Schuchert in 1932 and Longwell in 1944 to write papers opposing Wegenerʼs hypothesis. Simpson contributed with paleontologic opposition. In 1944 Holmes published a British textbook that showed how continental drift could change geology. It was Holmes, Carey, and Wilson, as much as the Americans Hess and Dietz, who should be credited with instigating the plate-tectonic revolution.
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... Although it was well researched and presented in a few respectable books by Wegener and other scientists, it was ridiculed by geologists and fossil experts. The strong evidence for it was kept out of geology textbooks and scientific journals for 40 years (Krill 2014). Then continental drift was corroborated by a new type of data-the magnetic record of rocks on the seafloor. ...
The aquatic ape hypothesis for human evolution can account for all the traits that distinguish humans from chimpanzees. This scientific paradigm has been considered impossible. It would require that human ancestors maintained a semiaquatic lifestyle for millions of years, whereas hominin fossils indicate relatively dry terrestrial environments. Here I propose a marine aquatic evolution that is speculative, but compatible with all the fossil and genetic evidence. In this hypothesis, hominins evolved from chimpanzee-like apes that became stranded on proto-Bioko — new volcanic islands with no terrestrial foods available. The apes were forced to eat shellfish and seaweed. From wading in water on two legs to obtain food, their bodies evolved to become bipedal. Naked skin, blubber, and protruding noses were also aquatic adaptations. Brain-size increase resulted from marine fatty acid DHA. Some of these hominins escaped to mainland Africa and their bipedal descendants are recorded at the famous fossil sites. The volcanic islands grew and evolved into Bioko, and the hominins that remained there evolved into Homo sapiens. They gave up their marine diet and semiaquatic habitat after food became available on the evolving island. Then, during one of the low sea-level stands in the Pleistocene epoch, humans walked to the mainland on the emergent Bioko land bridge. Unlike earlier aquatic ape ideas, the Bioko scenario can be tested by DNA. If the human genome includes a retrovirus that is otherwise only found in endemic animals on Bioko, it would show that our ancestors came from there. Unfortunately, Bioko and west-central Africa are not interesting to traditional paleoanthropologists, because they do not contain fossils.
The continental drift controversy has been deeply analysed in terms of rationalist notions, which seem to find there a unique topic to describe the weight of evidence for reaching consensus. In that sense, many authors suggest that Alfred Wegener’s theory of the original supercontinent Pangea and the subsequent continental displacements finally reached a consensus when irrefutable evidence became available. Therefore, rationalist approaches suggest that evidence can be enough by itself to close scientific controversies. In this article I analyse continental drift debates from a different perspective which is based on styles of thought. I’ll argue that continental drift debate took much longer than it was usually recognized with two styles of thought coexisting for hundreds of years. These were fixism and mobilism and they were always confronting their own evidence and interpretations and functioning as general frameworks for the acceptability of a specific theory. Therefore, this text aims to bring much broader sociological elements than usually involved in the analysis of the continental drift theory.
Earth as an Evolving Planetary System explores key topics and questions relating to the evolution of the Earth's crust and mantle over the last four billion years. This Second Edition features exciting new information on Earth and planetary evolution and examines how all subsystems in our planet-crust, mantle, core, atmosphere, oceans and life-have worked together and changed over time. Kent Condie synthesizes data from the fields of oceanography, geophysics, planetology, and geochemistry to address Earth's evolution. Two new chapters on the Supercontinent Cycle and on Great Events in Earth history New and updated sections on Earth's thermal history, planetary volcanism, planetary crusts, the onset of plate tectonics, changing composition of the oceans and atmosphere, and paleoclimatic regimes Also new in this Second Edition: the lower mantle and the role of the post-perovskite transition, the role of water in the mantle, new tomographic data tracking plume tails into the deep mantle, Euxinia in Proterozoic oceans, The Hadean, A crustal age gap at 2.4-2.2 Ga, and continental growth.