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Study Reveals Eukaryotic Life Evolved 3 Billion Years Ago

12/6/2025

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Summary

Story summary

A study from the University of Bristol finds complex eukaryotic life began evolving nearly 3 billion years ago, earlier than the roughly 2 billion-year estimate.
Using molecular clock analysis, researchers traced gene duplications across diverse organisms and found key eukaryotic traits emerged before mitochondria.
The archaeal ancestor of eukaryotes developed complex features in an anoxic environment, with mitochondrial symbiosis occurring later, around 2.2 billion years ago.

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Story summary

A study from the University of Bristol finds complex eukaryotic life began evolving nearly 3 billion years ago, earlier than the roughly 2 billion-year estimate.
Using molecular clock analysis, researchers traced gene duplications across diverse organisms and found key eukaryotic traits emerged before mitochondria.
The archaeal ancestor of eukaryotes developed complex features in an anoxic environment, with mitochondrial symbiosis occurring later, around 2.2 billion years ago.