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Updated: Jul 7, 2026

The Power of Simplicity: Sea Urchin Embryos as in Vivo Developmental Models for Studying Complex Cell-to-cell Signaling Network Interactions
Published on: February 16, 2017
From unicellularity to multicellularity - molecular speculations about early animal evolution
H F Hoenigsberg1, M H Tíjaro, C Sanabria
1Instituto de Genética Evolutiva y Biología Molecular and Instituto de Genética Ecológica y Biodiversidad del Trópico Americano, Bogotá D.C., Colombia. hoenigsberg@cable.net.com
Abstract:
A morphological, physiological, developmental, and genetic organization of great complexity ineluctably unfolded from relatively simple phenomena invested with enormous potential. Sometime long ago in the Protererozoic times, parasitic invasions caused lower evolutionary levels to integrate into higher-level selection. Therefore, we have a multi-level selection problem that ultimately revolves around the question of how natural selection among lower-level units acts to create higher-level units of selection, in which Darwinian competition among replicators ceases to be the foremost force. The first level relinquishes its independence for the benefit of a higher-level cooperative force that is now the criterion of fitness for the new transition in the evolutionary process.
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