Opisthokonts: True Posterior Flagellum

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And now the piece.

Opisthokonts: True Posterior Flagellum

~1.15 Billion Years Ago (+/- 50 million)

12 unique amino acids + glycogen energy storage + True Posterior Flagellum

Fungi and animals share a common ancestor within the Opisthokonts. At this point, neither were fungi or animals as we know them.

This is the birth of the “Pushers.” Our ancestors perfected the posterior flagellum, moving the single motor to the very back of the cell. This turned the cell into a biological torpedo. By pushing from the rear rather than pulling from the front, these cells gained incredible speed and stability in open water. This “rear-engine” configuration is the shared heritage of every animal and fungus on Earth, a high-performance design that defined our shared ancestor as an active, hunting consumer.

Key shift:

Divergence from proto-animal lineage
Likely unicellular, aquatic ancestors

Here's the key idea. About 1.15 billion years ago, our animial-fungi ancestor evolve a true posterior flagellum. Single-celled animal sperm has a lineage back to this ancestor.

Finally, the core takeaway. By 1.15 billion years ago, our animial-fungi ancestor evolve a true posterior flagellum. Single-celled animal sperm has a lineage back to this ancestor. Fungi will split off in about 200 million years from this point.

That Science Story,

was first published on TST 2 months ago.

The flashcard inspired by it is this.

All this is part of the broader TST project.

In this project, claims are never just asserted—they are attached to evidence, context, and traceable sources.

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The end!