| 单词 | Devonian period |
| 例句 | Shifts in sea levels during the Early-Middle Devonian period probably disrupted natural ocean barriers that had kept waters cooler at the South Pole. Waves of change: How sea-levels and climate altered the marine ecosystems at the South Pole 390-385 million years ago 2023-10-19T04:00:00Z The ability of gnathostomes to exploit new nutrient sources likely is one reason that they replaced most jawless fishes during the Devonian period. Fundamentals of Biology 2015-01-01T00:00:00Z Amphibians evolved in the Devonian period and were the earliest terrestrial tetrapods. Concepts of Biology 2013-04-25T00:00:00Z He concluded that all acoustic communication in vertebrates descended from a single ancestor 400 million years ago, which was the Devonian period when most species lived under water. Secret communication of sea animals discovered 2022-10-25T04:00:00Z Then, last year, supernova proponents suggested a similar scenario could explain a major extinction event 359 million years ago, at the end of the Devonian period. Exploding stars may have assaulted ancient Earth 2021-07-15T04:00:00Z Shifts in sea levels during the Early-Middle Devonian period probably disrupted natural ocean barriers that had kept waters cooler at the South Pole. Waves of change: How sea-levels and climate altered the marine ecosystems at the South Pole 390-385 million years ago 2023-10-19T04:00:00Z The fossil plant Elkinsia polymorpha, a “seed fern” from the Devonian period—about 400 million years ago—is considered the earliest seed plant known to date. Fundamentals of Biology 2015-01-01T00:00:00Z The end of the Devonian period, 359 million years ago, was an eventful time: Fish were inching out of the ocean, and fernlike forests were advancing on land. No asteroids or volcanoes needed: ancient mass extinction tied to ozone loss, warming climate 2020-05-27T04:00:00Z The discovery is particularly exciting because it comes from a planetary turning point, the Devonian period, when the first forests appeared on Earth. Daily briefing: Oldest fossil trees rewrite the history of forests 2019-12-19T05:00:00Z It lived about 372 million years ago during the Devonian period, and inhabited a shallow lagoon in a landmass that is now part of northwestern Russia. Early tetrapods had an eye on the land 2019-10-22T04:00:00Z Tetrapods got their start in the water about 400 million years ago in the Devonian period, evolving from fish with fleshy fins. RoboFossil Reveals Locomotion of Beast from Deep Time 2019-01-17T05:00:00Z Amphibians evolved during the Devonian period and were the earliest terrestrial tetrapods. Fundamentals of Biology 2015-01-01T00:00:00Z They were the first fossils of the Devonian period, about 390 million years ago, and were collected and studied in Brazil in 1870. A chronicle of loss at Brazil's National Museum, much of which was destroyed by fire 2018-09-04T04:00:00Z The museum, for example, housed Brachiopods, the first fossils of the Devonian period – approximately 390 million years ago – that collected and studied in Brazil in the 1870s. Brazil's national museum: what could be lost in the fire? 2018-09-03T04:00:00Z Granite prevails, but at Polperro we have cliffs belonging to the Lower Devonian period, and for some ten or twelve miles going west from Chapel Point we find rocks of the Silurian order. Climbing in The British Isles. Vol. 1 - England 2011-11-14T03:00:21.670Z I do not believe in the lapse of a long interval of time between the silurian and carboniferous deposits,—in fact, in a Devonian period. 4th. In the Arctic Seas A Narrative of the Discovery of the Fate of Sir John Franklin and his Companions 2011-10-10T02:00:18.377Z Fossils indicate that by the end of the Devonian period, ferns, horsetails, and seed plants populated the landscape, giving rising to trees and forests. Fundamentals of Biology 2015-01-01T00:00:00Z The great inland sea that covered the middle portion of the continent during the Silurian and the Devonian periods, became shallow by the deposit of vast quantities of sediment. Earth and Sky Every Child Should Know Easy studies of the earth and the stars for any time and place The trachyte of the Drachenfels was probably the neck of a volcano which burst through the fundamental schists of the Devonian period. Volcanoes: Past and Present In the Devonian period the cephalopods began to make a distinct advance in numbers, and in development. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 3 "Destructors" to "Diameter" Yet Sir R. Murchison refers them to the Devonian period—a period which had a large and varied marine Fauna. Essays: Scientific, Political, & Speculative, Vol. I A long time passed—thousands of years rolled by: then came real fishes and land plants in what is called the Devonian period, or the old red sandstone. Orthodoxy: Its Truths And Errors The wrinkling of the earth's surface which produced this range occurred during the Devonian period when fishes were the predominant inhabitants of the earth, many millions of years before birds or even reptiles appeared. The Book of the National Parks The Devonian period, including that of the Old Red Sandstone, was one of the most significant periods in the earth's history. The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told In the Devonian period the brachiopods reached the climax of their development: they compose three-quarters of the known fauna, and more than 1100 species have been described. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 3 "Destructors" to "Diameter" We have seen that one ray in each year since the Devonian period will build the fully formed halo: an object unlike any other appearance in the rocks. The Birth-Time of the World and Other Scientific Essays There are, however, many more localities in which one would find the Carboniferous rocks resting unconformably upon the Silurians without the intervention of any strata which could be referred to the Devonian period. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science In the neighborhood of Pittsburgh, this is usually found at a depth of 1,300 to 1,500 feet, in what is known as the Third Oil Sand, a sandstone of the Devonian period. Burroughs' Encyclopaedia of Astounding Facts and Useful Information, 1889 It was a much less strenuous time than the Devonian period; it was like a very long summer. The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told At the close of the Devonian period, several upheavals occurred of great significance for the future history of America. The Atlantic Monthly, Volume 11, No. 67, May, 1863 The fishing-ground of the geologist in the Silurian and Devonian periods is even more circumscribed than his, and belongs, besides, not to a living, but to a dead world, far more difficult to decipher. The Atlantic Monthly, Volume 11, No. 66, April, 1863 In the Devonian period, there is an intermediate state of things, the genus Chonetes being continued in new and varied types, and the Carboniferous Produdœ being represented by many forms of the allied group Productella. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science Trilobites were very common in the Silurian and Devonian periods, but became extinct at the close of the Paleozoic. The Gutenberg Webster's Unabridged Dictionary Section T, U, V, and W This appeared and flourished throughout the Devonian period, if not anterior to it, and long before the appearance of batrachian reptiles and other low air-breathing forms of life. Life: Its True Genesis If we had looked for them in the Devonian period, we should have found many with looser coils than these, and some only slightly curved in the shape of a horn. The Atlantic Monthly, Volume 11, No. 67, May, 1863 The Stromatopora are among the chief limestone builders of the Silurian and Devonian periods. The Elements of Geology On this view, the typical Devonian rocks of Europe, Britain, and North America are the deep-sea deposits of the Devonian period, or, at any rate, are genuine marine sediments formed far from land. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science Although the precise age of such copper lodes can not be defined, we may safely affirm that they were either filled at the close of the Silurian or commencement of the Devonian period. The Student's Elements of Geology "Jupiter is evidently passing through a Carboniferous or Devonian period such as existed on earth, though, if consistent with its size, it should be on a vastly larger scale," said the doctor. A journey in other worlds A romance of the future The Devonian period had opened with a rise of the land, but the sea eat steadily into it once more, and, with some inconsiderable oscillations of the land, regained its territory. The Story of Evolution Taken as a whole, the Crustacean fauna of the Devonian period presents many alliances with that of the Upper Silurian, but has only slight relationships with that of the Lower Carboniferous. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science The Echinoderms of the Devonian period call for little special notice. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science The sub-kingdom of the Vertebrates is still represented by Fishes only; but these are so abundant, and belong to such varied types, that the Devonian period has been appropriately called the "Age of Fishes." The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science They commence their existence, so far as known, in the Devonian period, but they attain their maximum in the Carboniferous; and—unlike the Lepidodendroids—they are not known to occur in the Permian period. The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science We have an even greater difficulty here, as plant remains are not preserved at all until the Devonian period. The Story of Evolution The migration had probably proceeded throughout the Devonian period, especially from the calmer shores of the inland seas. The Story of Evolution |
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