CALM model of eukaryogenesis

An illustration of the beginnings of multicellular life, showing how the complexity of cellular life increases with the progression of the Great Oxidation Event.

The new, proposed model for the evolution of complex life, or eukaryogenesis, dubbed CALM (Complex Archaeon, Late Mitochondrion). Built on hundreds of genetic sequences across biological systems and the fossil record, this new evidence-based framework nuances our understanding of the differentiation of eukaryotes from prokaryotes and places the development of mitochondria significantly later than other internal structures, contrary to current models of evolution.

Date:
04 December 2025
Credit:
Christopher Kay

Copyright OIST (Okinawa Institute of Science and Technology Graduate University, 沖縄科学技術大学院大学). Creative Commons Attribution 4.0 International License (CC BY 4.0).

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