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First Animal Egg Layers

By Michael Alan Prestwood

Sun 31 Mar 2024
Published 2 years ago.
Updated 1 month ago.
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First Animal Egg Layers

~620 Million Years Ago (+/- 20 million)
tissue-level reproduction

The evolution of egg-laying evolved before fish. It is thought to have developed with or shortly after the emergence of the first multicellular animals, around 640 million years ago.

  • Kingdom: Animalia > Phylum: Porifera (sponges) and Cnidaria (jellyfish, corals, etc.)

— map / TST —

Michael Alan Prestwood
Author & Natural Philosopher
Prestwood writes on science-first philosophy, with particular attention to the convergence of disciplines. Drawing on his TST Framework, his work emphasizes rational inquiry grounded in empirical observation while engaging questions at the edges of established knowledge. With TouchstoneTruth positioned as a living touchstone, this work aims to contribute reliable, evolving analysis in an emerging AI era where the credibility of information is increasingly contested.
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