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MULTICELLULARITY. "Multicellularity has evolved independently at least 46 times, including in some prokaryotes, like cyanobacteria, myxobacteria, actinomycetes, Magnetoglobus multicellularis or Methanosarcina. However, complex multicellular organisms evolved only in six eukaryotic groups: animals, fungi, brown algae, red algae, green algae, and land plants." https://lnkd.in/dCyD_7R View in LinkedIn

SECOND BOTHERSOME ISSUE. "Yet, eukaryotes evolved only once in the history of life, whereas multicellular eukaryotes have evolved many times." https://lnkd.in/dNEtvR8 View in LinkedIn

EUKARYOTE AND MULTICELLULAR EQUIVALENCY. "According to multi-level theory, evolutionary transitions require mediating conflicts between lower-level units in favour of the higher-level unit. By this view, the origin of eukaryotes and the origin of multicellularity would seem largely equivalent." https://lnkd.in/dNEtvR8 View in LinkedIn

DEATH OF A SNOWFLAKE. "Shortly after snow precipitation, every single snowflake experiences unique structural changes determined by its specific geometry, dimensions, orientation, and local environment. Accompanied by the physical rearrangement of snowflakes, these changes result in the structural evolution of the snowpack over time. The process is known as snow metamorphism." Lovely article. https://lnkd.in/dU4PZ_d View in LinkedIn

STUCK OR BETTER OFF? "Why have not prokaryotes evolved complex multicellularity?" https://lnkd.in/dNEtvR8 View in LinkedIn

TIME LAPSES of a growing snowflakes. "These are not computer simulations, but are real slivers of ice grown in the laboratory. I photograph the crystals as they grow, controlling their shapes by changing the temperature and humidity as they form. The final shape depends on the entire growth history." http://www.snowcrystals.com/videos/videos.html View in LinkedIn

NO SURVIVING INTERMEDIATES. "Regardless of how early eukaryotes escaped from their predicament, it is plain that the problems faced by a prokaryotic host cell with bacterial endosymbionts are serious, if not irreconcilable, and go a long way towards explaining why there are no surviving evolutionary intermediates between prokaryotes and eukaryotes." https://lnkd.in/dNEtvR8 View in LinkedIn

THIRD BOTHERSOME USSUE. "Why have not prokaryotes evolved complex multicellularity? Their analysis points out crucial differences between prokaryotes and eukaryotes in the availability of energy and the role of energetic differences in the capacity for gene expression." https://lnkd.in/dNEtvR8 View in LinkedIn

EMERGENT REDOX STATE. "By contrast, metabolic signalling is a shared primitive feature of all cells. Redox state of the cytosol is an emergent feature that cannot be subverted by an individual symbiont." https://lnkd.in/dNEtvR8 View in LinkedIn

ENDOSYMBIONT ORIGINS. "Genome transfer diminishes the heritable variation of the symbiont, but requires the de novo evolution of the protein-import apparatus and was opposed by selection for selfish symbionts." https://lnkd.in/dNEtvR8 View in LinkedIn