That life is hierarchically organized, with species composed of populations, populations of individuals, individuals of cells, cells of organelles, organelles of genomes, genomes of chromosomes, and chromosomes of genes, is so obvious an observation that it is quite remarkable that we have no general explanation of why this is so. –Leo Buss, The Evolution of Individuality, p. 183
Buss, L.W. 1987. The Evolution of Individuality. Princeton: Princeton University Press.
I don’t understand how it could be otherwise unless created by supernatural magic. Why stop with genes and not continue on with molecules and atoms and subatomic particles? Why does it need explaining? What sort of explanation is he looking for? This seems like asking “why did you make all the gears and housing of that watch first instead of just making the whole watch at once?”
What am I missing here?
Context, which is my fault. Buss is coming at it from the other side, asking not “why are individuals made of cells” but “why did cells form individuals” (and so on: why did genes form chromosomes, why did chromosomes form genomes, why did prokaryotes get together to form eukaryotes, etc.). The ‘general explanation’ Buss is looking for here is what Maynard Smith and Szathmáry tried to answer eight years later in The Major Transitions in Evolution.
Ah, I see, that’s different. 🙂 But I still think the fault is his, since he arranged the hierarchy in his paragraph from top down, rather than bottom up. It’s a reasonable question to ask why things kept joining to build bigger things, but kind of odd to ask why big or complex things are made of smaller things, which is what he was actually asking the way he organized the question.