15.The other main reason for autocatalysis is that new technologies and materials make it possible to generate still other new technologies by recombination.
18.Within the original host, let's say a duck, the virus may mutate over time: either independently, or by recombination with a gene segment from a different virus.
20.It is the endless recombinations of our genomes - each nearly identical, but not quite - that make us what we are, both as individuals and as a species.