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In 2002, a study looked at the fossil skulls of two large canids that had been found buried 2 metres and 7 metres from what was once a mammoth-bone hut at this Upper Paleolithic site, and using an accepted morphologically based definition of domestication declared them to be "Ice Age dogs". The carbon dating gave a calendar-year age estimate ...
The two obtained the first isotope of this element, 234m Pa, that had been predicted by Mendeleev in 1871 as a member of the natural decay of 238 U: they named it brevium. A longer-lived isotope 231 Pa was found in 1918 by Otto Hahn and Lise Meitner , and was named by them protoactinium: since it is longer-lived, it gave the element its name.
This list of chemical elements named after places includes elements named both directly and indirectly for places. 41 of the 118 chemical elements have names associated with, or specifically named for, places around the world or among astronomical objects.
Carbon was discovered in prehistory and was known in the forms of soot and charcoal to the earliest human civilizations. Diamonds were known probably as early as 2500 BCE in China, while carbon in the form of charcoal was made by the same chemistry as it is today, by heating wood in a pyramid covered with clay to exclude air. [108] [109]
The Carboniferous (/ ˌ k ɑːr b ə ˈ n ɪ f ər ə s / KAR-bə-NIF-ər-əs) [6] is a geologic period and system of the Paleozoic era that spans 60 million years from the end of the Devonian Period 358.86 Ma (million years ago) to the beginning of the Permian Period, 298.9 Ma.
Clade A included 64% of the modern dogs sampled, and these are a sister group to a clade containing three fossil pre-Columbian New World dogs dated between 1,000 and 8,500 YBP. This finding supports the hypothesis that pre-Columbian New World dogs share ancestry with modern dogs and that they likely arrived with the first humans to the New World.
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Using two different methods to remove all known gases from air, Ramsay and Lord Rayleigh were able to announce in 1894 that they had found a monatomic, chemically inert gaseous element that constituted nearly 1 percent of the atmosphere; they named it argon.