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SINGULAR EVENT. "So, why did prokaryotes not evolve into eukaryotes more than once? The reason is that it is impossible to generate this amount of energy in a single cell unless that cell has a powerhouse of energy production with a large membrane surface — that is, a mitochondrion." https://lnkd.in/dz-st9e View in LinkedIn

FRAGMENT FROM NATURE continues from last weekend with a consideration of the biology of spider webs, how they arose, and how and why they function as they do. It is a lovely story of inventiveness at many scales: the molecular design of the material with sliding hydrogen bonds giving it toughness; the various positioning of the webs giving rise to substrate freedom; and the web geometry that exploits efficiency of an expensive material with high functionality for a powerful prey. View in LinkedIn

HYDROGEN POWERED train in Germany. https://lnkd.in/dXv_6qC View in LinkedIn

FALSE PREMISE 4. "Fourth, and perhaps most importantly, it is difficult and may be impossible to eliminate eukaryocentric bias from the measures by which eukaryotes as a whole are judged to have achieved greater success than prokaryotes as a whole." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

FALSE PREMISE 3. "Third, identifying which of several complex cellular features confer on eukaryotes a putative richer evolutionary potential remains an area of speculation: various keys to success have been proposed and rejected over the five-decade history of research in this area." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

FALSE PREMISE 2. "Second, eukaryogenesis confronts evolutionary theory in ways not different from other evolutionary transitions in individuality; parallel systems can be found at several hierarchical levels." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

FALSE PREMISE 1. "First, the criteria by which we judge eukaryogenesis to have required a genuinely unlikely series of events 2 billion years in the making are being eroded by discoveries that fill in the gaps of the prokaryote:eukaryote “discontinuity.”." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

WAS IT SINGULAR? "Scientific and popular rhetoric extolling this event as a singularity lacks rigorous evidential and statistical support. Here, we question several of the usual claims about the specialness of eukaryogenesis, focusing on both eukaryogenesis as a process and its outcome, the eukaryotic cell." http://www.pnas.org/content/112/33/10278.full View in LinkedIn

HIT BY LIGHTNING. "Eukaryogenesis is widely viewed as an improbable evolutionary transition uniquely affecting the evolution of life on this planet." https://lnkd.in/d6GwkCt View in LinkedIn

EUKARYOTES EVOLUTION. "Most hypotheses have been inferred from studying the biology of modern organisms. Eukaryotes may have evolved from prokaryotes because: (1). Both use RNA and DNA are the genetic material; (2). Both use the same 20 amino acids; (3). Both have ribosomes and DNA and RNA; (4). Both have a lipid bilayer cell membrane; (5). Both use L amino acids and D sugars." https://lnkd.in/dCVM9yX View in LinkedIn