L'idée que la cellule eucaryote est un symbionte de cellules procaryotes est principalement l'oeuvre de L. Margulis. Cette idée a pris longtemps à être acceptée, et elle ne l'est pas encore totalement. D'après moi, c'est un excellent exemple montrant comment les points de vue changent en science quand les faits appuient une théorie.
Jean-François
P.S.: Margulis L, Bermudes D. (1985) Symbiosis as a mechanism of evolution: status of cell symbiosis theory. Symbiosis;1:101-24
"Several theories for the origin of eukaryotic (nucleated) cells from prokaryotic (bacterial) ancestors have been published: the progenote, the direct filiation and the serial endosymbiotic theory (SET). Compelling evidence for two aspects of the SET is now available suggesting that both mitochondria and plastids originated by symbioses with a third type of microbe, probably a Thermoplasma-like archaebacterium ancestral to the nucleocytoplasm. We conclude that not enough information is available to negate or substantiate another SET hypothesis: that the undulipodia (cilia, eukaryotic flagella) evolved from spirochetes. Recognizing the power of symbiosis to recombine in single individual semes from widely differing partners, we develop the idea that symbiosis has been important in the origin of species and higher taxa. The abrupt origin of novel life forms through the formation of stable symbioses is consistent with certain patterns of evolution (e.g punctuated equilibria) described by some paleontologists."
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