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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

RANDOM MUTATIONS SUBJECTED TO SELECTION. "Mutations can be beneficial, neutral, or harmful for the organism, but mutations do not "try" to supply what the organism "needs." In this respect, mutations are random — whether a particular mutation happens or not is unrelated to how useful that mutation would be." https://lnkd.in/daGhbNn View in LinkedIn

REGULATORY ELEMENT MUTATIONS. "Mutation creates variations in protein-coding portions of genes that can affect the protein itself. But even more often, it creates variations in the "switches" that control when and where a protein is active and how much protein is made." https://lnkd.in/d9VF6RH View in LinkedIn

ALLELES. "The whole human family is one species with the same genes. Mutation creates slightly different versions of the same genes, called alleles. These small differences in DNA sequence make every individual unique. They account for the variation we see in human hair color, skin color, height, shape, behavior, and susceptibility to disease." https://lnkd.in/d9VF6RH View in LinkedIn

FRESH VARIATION. "Most commonly, a single base is substituted for another. Sometimes a base is deleted or an extra base is added. Fortunately, the cell is able to repair most of these changes. When a DNA change remains unrepaired in a cell that will become an egg or a sperm, it is passed down to offspring. Thanks to mutation, we all have some new variations that were not present in our parents." https://lnkd.in/d9VF6RH View in LinkedIn

SO ENDS this brief peek into the topic of the improbability of evolution and the emergence of life. This is a bone that many dogs have chewed in, both within science and within philosophy and beyond, because it is a core issue, central to the whole question of biology. Kicking the can into panspermia, life arising beyond earth, simply delays the core question, it does not do away with it. View in LinkedIn