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Updated: Jul 12, 2026
12:24
Quantifying Yeast Chronological Life Span by Outgrowth of Aged Cells
Published on: May 6, 2009
Summary
Eukaryotic organisms, characterized by nucleated cells, were diverse by 850 million years ago. Evidence suggests these complex life forms may have first appeared as early as 1400 million years ago.
Area of Science:
- Paleobiology
- Geology
- Evolutionary Biology
Background:
- The origin and early evolution of eukaryotic life are key questions in biology.
- Understanding the timeline of eukaryotic emergence provides insights into early life on Earth.
Purpose of the Study:
- To determine the earliest appearance and diversification of eukaryotic organisms.
- To establish a timeline for the establishment of nucleated cells in Earth's history.
Main Methods:
- Analysis of Precambrian sedimentary rock formations.
- Microscopic examination of fossilized organic material within ancient sediments.
Main Results:
- Sedimentary evidence indicates that nucleated (eukaryotic) organisms were well-established and diverse approximately 850 +/- 100 million years ago.
- Eukaryotes likely existed, and may have first appeared, as early as 1400 +/- 100 million years ago.
Conclusions:
- The Precambrian fossil record supports an early origin and significant diversification of eukaryotes.
- This timeline pushes back the known history of complex cellular life on Earth.
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