transitional fossil

noun

Definition of transitional fossil

:a fossil that exhibits characteristics of both ancestral and derived forms
  • During the past 30 years, new discoveries and reinvestigations of long-forgotten specimens have coalesced into a flood of transitional fossils. Paleontologists have unearthed walking whales from Pakistan, feathered dinosaurs from China …
  • Courier News (Bridgewater, New Jersey)27 Feb. 2011
  • However, although the mammal and bird origins are both documented by numerous transitional fossils, turtles appear abruptly.
  • —Michael S. Y. LeeScience24 Sept. 1993

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First Known Use of transitional fossil

1850


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