<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (July 2010) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (July 2010) (Learn how and when to remove this template message) </Td> </Tr> <P> In Arthur C. Clarke's Space Odyssey, Monoliths are machines built by an unseen extraterrestrial species . In the series of novels (and the films based on these), three Monoliths are discovered in the solar system by humans . The response of the characters to their discovery drives the plot of the series . It also influences the fictional history of the series, particularly by encouraging humankind to progress with technological development and space travel . </P> <P> The first Monolith appears at the beginning of the story, set in prehistoric times . It is discovered by a group of hominids and somehow triggers a considerable shift in evolution, starting with the ability to use tools and weaponry . It is later revealed that thousands of other monoliths exist elsewhere in the solar system . </P>

What is the monolith in 2001 a space odyssey
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