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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

EUKARYOTIC CONFLICT. "Energy-converting endosymbionts that allow eukaryotes to transcend surface-to-volume constraints also can allocate energy into their own selfish replication. This principal conflict in the origin of eukaryotes can be mediated by genetic or energetic mechanisms." A reference to mitochondria and chloroplasts. https://lnkd.in/dNEtvR8 View in LinkedIn

MOST MULTICELLULAR CREATURES are eukaryotes (83% of all species, with nucleated cells with other organelles enclosed within membranes), but not all eukaryotes are multicellular (many are unicellular -- amoeba, paramecium, yeast, etc). Most prokaryotes (without membrane-bound nucleus or organelles) are not generally considered multicellular although bacteria can form operational colonies (i.e.: cyanobacteria, etc) and biofilms (i.e.: many bacteria) with quorum sensing communication. But the colonies lack organs. Also some prokaryotes may have multicellular stages in their life cycle (i.e.: myxobacteria). But overall, 99% of prokaryotes are unicellular. https://lnkd.in/d7tJtht View in LinkedIn

SO ENDS this first part on Kepler's snowflake. In part because the properties of water are unusual, snowflake geometry and features are also unusual. Having words for things permits humans to discern differences: the old platitude about Eskimo words for snow turned out to be less than clear. But today, science has added new concepts to Kepler's snowflake, based on the quirky properties of water, allowing us a new perception of those beguiling geometries that occupied Kepler. https://lnkd.in/dKmcYGd View in LinkedIn

LOW ENERGY SYMMETRY. "When a liquid freezes, the molecules tend to settle in the lowest-energy state, and that almost always involves some form of symmetry. The higher the symmetry, the more stable the crystal is." http://www.scientificamerican.com/article/why-are-snowflakes-symmet/ View in LinkedIn

CRYSTALLIZATION. "During this process, the molecules (in this case, water molecules) align themselves to maximize attractive forces and minimize repulsive ones. As a result, the water molecules arrange themselves in predetermined spaces and in a specific arrangement. This process is much like tiling a floor in accordance with a specific pattern: once the pattern is chosen and the first tiles are placed, then all the other tiles must go in predetermined spaces in order to maintain the pattern of symmetry." http://www.scientificamerican.com/article/why-are-snowflakes-symmet/ View in LinkedIn

SNOWFLAKE YEAST. "Snowflake-phenotype yeast have a novel multicellular life history that responds to selection. As snowflake yeast evolved a twofold increase in size at reproduction over 14–60 transfers, propagule size declined from 40 to 20% of parental size." http://www.pnas.org/content/109/5/1595.full View in LinkedIn

ITERATIVE PROCESS. "Subsequently, if conflicts can again be mediated, these higher-level units themselves can band together to form even higher-level units. The history of life can thus be viewed as a repetition of stages of cooperation leading to conflict, and conflict mediation leading to emergence. This process underlies many transitions in evolution, and these transitions are thus in some sense equivalent." https://lnkd.in/dNEtvR8 View in LinkedIn

EMERGENT TRAITS. "We investigated the transition between unicellular and multicellular life by studying two emergent traits of multicellular snowflake-phenotype yeast, cluster reproduction, and settling survival. New clusters can potentially arise by production of either unicellular or multicellular propagules." http://www.pnas.org/content/109/5/1595.full View in LinkedIn