Use 'progenitor' to highlight a historical connection or influence on present entities. The Greek philosophers were the progenitors of Western philosophy.
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Biological Context
'Progenitor' is often used in biology to discuss origins of species or cells. These fossils represent the progenitors of modern birds.
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Not Contemporary
It usually refers to something that existed in the past, not current individuals or entities. The steam engine was a progenitor to modern locomotives.