Scoop | Whereas speciation by accumulation of "random DNA mutations" has never been adequately documented, a plethora of high-quality scientific studies has unequivocally shown symbiogenesis to be at the basis of the origin of species and more inclusive taxa.
Members of at least two prokaryotic domains (a sulfidogenic archaebacterium, a sulfide-oxidizing motile eubacterium) merged in the origin of the earliest nucleated organisms to evolve in the mid-Proterozoic Eon (c. 1200 million years ago).
Such a heterotrophic, phagocytotic motile protoctist was ancestral to all subsequent eukaryotes (e.g., other protoctists, animals, fungi and plants).
The defining seme of eukaryosis, the membrane-bounded nucleus as a component of the karyomastigont, evolved as Thermoplasma-like archaebacteria and Perfilievia-Spirochaeta-like eubacteria symbiogenetically formed the amitochondriate LECA (the Last Eukaryotic Common Ancestor). Their co-descendants (that still thrive in organic-rich anoxic habitats) are amenable to study so that our videos of them will be shown here.
There are no missing links in our scenario. Contemporary photosynthetic (green) animals (e.g., Elysia viridis, Convoluta roscoffensis), nitrogen-fixing fungi (Geosiphon pyriforme), cellulose digesting animals (cows, Mastotermes darwiniensis termites) and plants (Gunnera manicata) make us virtually certain that Boris Mikhailovich Kozo-Polyansky's (1890-1957) analysis (Symbiogenesis: A New Principle of Evolution, 1924) was and still is correct.
Symbiogenesis accounts for the origin of hereditary variation that is maintained and perpetuated by Charles Darwin's natural selective limitations to reaching the omnipresent biotic potential characteristics of any species.
