When would you speculate that the extinction of most eukaryal life forms without mitochondria would have begun?

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Quizplus · Accepted Answer

The extinction of most eukaryal life forms without mitochondria likely began around 2 billion years before present (ybp), which corresponds with the time period when mitochondria, through endosymbiosis, became a critical component of eukaryotic cells, providing them with the ability to efficiently produce energy through aerobic respiration.

When Would You Speculate That the Extinction of Most Eukaryal