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MACRO REFLECTS MICRO. "Kepler pondered the question of why snow crystals always exhibit a six-fold symmetry. Although he doesn't refer to the atomistic viewpoint, Kepler does speculate that the hexagonal close-packing of spheres may have something to do with the morphology of snow crystals." https://lnkd.in/dmA4BAK View in LinkedIn

MANY EUKARYOTIC MULTICELLULARITY EVENTS. "The data suggest that eukaryotes are monophyletic. Equally uncontroversial is the evidence that many eukaryotic lineages have independently evolved some form of multicellularity. To reflect the ease of this transition, Grosberg & Strathmann characterize multicellularity as a ‘minor major transition’." https://lnkd.in/dNEtvR8 View in LinkedIn

BIG EFFICIENT TOOLKIT. "By their view, the mitochondrial endosymbiosis coupled with the accumulation of mitochondrial genes in the nuclear genome allowed tight regulation of respiration at relatively low cost in terms of genome size. This genetic and bioenergetic complexity allows eukaryotes to then easily evolve complex multicellularity." 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

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