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FRAGMENT FROM NATURE this weekend features some articles that discuss the freaky improbability of evolution. It is simply one of biology’s burrs under the skin. A very big one. Skeptics have had a field day on the topic, but the irksome fact remains that we can observe evolution on our timescales today both in microorganisms like yeast and bacteria and also in creatures like birds. It may be a burr, but its existence is irrefutable. View in LinkedIn

HORIZONTAL GENE TRANSFER. "The origin of bacterial genes in eukaryotes. In addition to gene duplication, horizontal gene transfer events have played a major role in the emergence of the eukaryotic cell, as is evident by the significant amount of genes that clearly are of bacterial origin that reside on eukaryotic genomes." https://lnkd.in/ewbMda5 View in LinkedIn

"MUTATION is a natural process that changes a DNA sequence. And it is more common than you may think. As a cell copies its DNA before dividing, a "typo" occurs every 100,000 or so nucleotides. That's about 120,000 typos each time one of our cells divides." Add to the horizontal gene transfer and you have a sloshing bucket of genes. https://lnkd.in/d9VF6RH View in LinkedIn

THE CONCEPT OF SPECIATION, a central part of evolution troubled by an unsolved definition, is in fact solved by thinking of variants or strains instead of species, instead of the idea of an immutable species with a clear species barrier. View in LinkedIn

THE GREATEST ACCIDENT. " How did life begin? I (and most scientists) would answer, “By accident.” But what an absolutely unlikely accident it must have been!" (George M Whitesides). https://lnkd.in/dv77eVE View in LinkedIn

REPLICATION, VARIATION, FITNESS. "Evolution as a process requires the presence of three simple elements: replication, variation and differential fitness. Replication allows for inheritance, and in particular the inheritance of variations, introduced by different mechanisms of mutation. These variations are then selected for or against via the competition of individuals over limited resources. The competition leads to differential fitness." Don't forget some reproductive isolation by speciation. https://lnkd.in/dGC6A7c View in LinkedIn

NO BRIGHT LINE. "Some kind of selection was needed in the chemical world before the emergence of evolution so that ‘it is meaningless to draw a strict line between the two worlds’." https://lnkd.in/dS2NY3q View in LinkedIn

ANALOGY WITH LIFE IS CLOSER. "What has changed in the past fourteen years is that the analogy with biological organisms is no longer highly tenuous." (George Dyson). https://lnkd.in/dVwXzv5 View in LinkedIn

GRADIENT OF LIFE. "The hypothesis that the origin of life may have proceeded stepwise through states of partial ‘aliveness’, which is the obvious consequence of a scientific view that a sharp transition is not physically realizable because of its improbability, is therefore sufficient to outline the nature of the process leading to life as we know it, one grounded solely on established laws of physics and chemistry." https://lnkd.in/dS2NY3q View in LinkedIn

LIVING OS. "Now, there are moves afoot to get the same code-Windows, or Windows CE, or Windows NT or whatever, not to mention underlying protocols-running everywhere. The thing is, it's happening. Which is very much what's gone on in the world of biology. In biology there is one operating system, and it's the one we're stuck with-the DNA/RNA operating system. All living organisms, with very rare exceptions, run that same system." https://lnkd.in/dVwXzv5 View in LinkedIn