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Evolution of cells refers to the evolutionary origin and subsequent evolutionary development of cells. Cells first emerged at least 3.8 billion years ago [1][2][3] approximately 750 million years after Earth was formed. [4]
The genetic history of the Indigenous peoples of the Americas is divided into two distinct periods: the initial peopling of the Americas from about 20,000 to 14,000 years ago (20–14 kya), and European contact, after about 500 years ago. [1][2] The first period of the genetic history of Indigenous Americans is the determinant factor for the ...
The appearance of the first eukaryotic cells in the fossil record were relatively followed by evidence of complex multicellular life. Rocks in Nevada dating back to a billion years ago preserve trace fossils left behind by worms as they burrowed below the sediment. [3] Other complex Precambrian life forms were preserved in North Carolina [4 ...
Late Devonian: 375 million years ago, 75% of species lost, including most trilobites. End Permian, The Great Dying: 251 million years ago, 96% of species lost, including tabulate corals, and most trees and synapsids. End Triassic: 200 million years ago, 80% of species lost, including all conodonts. End Cretaceous: 66 million years ago, 76% of ...
Map of early human migrations based on the Out of Africa theory; figures are in thousands of years ago (kya). [1]The peopling of the Americas began when Paleolithic hunter-gatherers (Paleo-Indians) entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the ...
Lacks c. 1945–1951. [A] Henrietta Lacks (born Loretta Pleasant; August 1, 1920 – October 4, 1951) [2] was an African-American woman [5] whose cancer cells are the source of the HeLa cell line, the first immortalized human cell line [B] and one of the most important cell lines in medical research. An immortalized cell line reproduces ...
The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s. In this theory the internal contents of cells were called protoplasm and described as a jelly-like
Enabling technology for mobile phones was first developed in the 1940s but it was not until the mid-1980s that they became widely available. By 2011, it was estimated in Britain that more calls were made using mobile phones than wired devices. [1] The history of mobile phones covers mobile communication devices that connect wirelessly to the ...