Thanks for the link. It should be noted that the actual meaning of "complex life" that is used in the title is "other multicellular living beings besides red a

Thanks for the link. It should be noted that the actual meaning of "complex life" that is used in the title is "other multicellular living beings besides red algae and green algae". Multicellular red algae and green algae have appeared many hundred million years before what is described in the paper. Moreover, multicellular cyanobacteria have existed for a much longer time, but their cellular differentiation is much simpler than in multicellular eukaryotes. Even more accurately, the "complex life" from the title actually means "animals + whatever multicellular relatives of animals might have existed, but they have disappeared by the Cambrian". The other multicellular eukaryotes, besides red algae, green algae and animals, have appeared much later (with the possible exception of fungi). Unlike multicellular algae or animals, the multicellular fungi have appeared on dry land, not in water. It is not known yet when this has happened. Fungi existed by the time of the appearance of land plants, which is much later than the events described in the paper, but it is not impossible that they may have appeared a few hundred million years earlier, in symbiosis with terrestrial cyanobacteria and/or green algae.