Fun coursera on virology.
Viruses are so numerous (10³⁰) and filling up everywhere. It gives this Boltzmann flavour of 'enough stuff" to really do statistics on.
Viruses are just a bundle of {proteins, lipids, nucleic acids} with a shell. It's totally value-free, no social Darwinism or "survival of the fittest" being imbued with a moral colour. Just a thing that happened that can replicate.
Maybe this is just because I was reading about nuclear spaces (⊂ topological vector space) and white-noise processes that I think of this. Viruses have a qualitatively different error structure than Gaussian. Instead of white-noise it's about if they can get past certain barriers, like:
survive out in the air/water/cyanide
bind to a DNA
spread across a population
adapt to the host's defences
... it seems like a mathematician or probabilist could use the viral world of errors to set out different assumptions for a mathematical object that would capture the broad features of this world that's full of really tiny things but very different to gas particles.
Did I mention that I love how viral evolution is totally value-neutral and logic-based?
Did I mention how I love that these things are everywhere all the time, filling up the great microspace my knowledge had left empty between man > animals > plants > ... > bacteria > ... > minerals?