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Длинная и нелицеприятная рецензия (англ.) Давида Бараша на последнюю книгу американского биолога Стефана Гулда The Structure of Evolutionary Theory. Бараш довольно хорошо описывает (презрительное) отношение мейнстримной социобиологии к работам и идеям Гулда.

Есть один момент, который я никак не могу понять - спор о том, что является единицей отбора в естественном отборе (unit of selection) -- происходит ли отбор на уровне генов, на уровне организмов или на уровне видов? Я не очень понимаю, о чём собственно идёт спор -- об определениях или о чём-то реальном?

Вот длинная цитата из рецензии Бараша:

First, levels of selection. Darwin maintained that the individual organism was paramount. Recent neo-Darwinians (especially sociobiologists such as Dawkins, Trivers, and George C. Williams, with crucial technical underpinning from William D. Hamilton) have modified this to emphasize selection at the gene level, based principally on the fact that genes - unlike species, groups, or even individuals - are persistent “replicators,” which selection can maintain, promote, or extinguish over time. Gould demurs. He argues for a hierarchical structure of selection, incorporating “gene, cell lineage, organism, deme, species and clade.” But why stop there? What about selection among communities, ecosystems, biomes, planets, star systems, galaxies?

To some degree, it is much ado about nothing, since even arch-reductionists acknowledge that selection operates at many different levels simultaneously, just as the gravitational effects of a falling cantaloupe and of the sun operate upon the orbit of Mars. But the resulting “cantaloupe effect” can effectively be ignored, even though it is not only theoretically defensible, but indisputable. Gould argues that hierarchies are unavoidable (in evolution, mind you, not human society!) and although he labors mightily - and, in my mind, unsuccessfully - for rehabilitating the species as a key level of selection, he disavows any downward hierarchy, notably selection at the level of genes, where in fact it is most cogent. He even speaks of gene selection in the past tense, as though it has somehow been disproved; e.g., “Nevertheless, the theory could not work. However stubborn and heroic the attempt, explanations inevitably faltered upon the central logical error - especially when selection had clearly worked upon emergent properties of higher-level individuals, and no verbal legerdemain could recast the story in terms of genes as causal agents.” [pg. 614]

Au contraire, Gould’s verbal legerdemain cannot cast this story other than in terms of genes as causal units. “The ‘goal’ of a unit of selection,” he writes, “is concentration by plurification - that is, the differential passage of ‘youness’ into the next generation, an increase in relative representation of your heritable attributes (whether you pass yourself on as a whole, or in disaggregated form, into the future of your lineage).” [pg. 621] Leave aside such Gouldisms as “plurification” and “youness.” And grant Gould’s insistence that organisms, not genes, operate in the real world as the immediate locus of differential reproduction (something that no gene selectionist would deny). There can be no doubt that such differential reproduction results in a difference among alternative alleles respecting their representation in future generations. This difference is natural selection.

“An entity must be able to reproduce,” he writes

to be defined as an evolutionary individual, but this entity need not replicate faithful copies of itself. Rather, it needs to be able to plurify - that is, to increase, relative to other individuals, the representation of its hereditary contribution to the next generation. Integral ‘you’ may be disaggregated in the process, but so long as you operated as an active causal agent of the Darwinian struggle while you lived, then you qualify as a unit of selection … [pg. 622]

But what is it that makes up one’s “contributions”? Genes, that’s what. How can genes not be a unit of selection? Maybe even the unit.

But according to Gould, any such focus on gene selection involves a crucial error: “mistaking bookkeeping for causation.” Indeed, he likes this phrase so much that he says it over and over, as though such mantric repetition will make it so. His point is that differential reproduction (of organisms, and - his particular hobby-horse - of species) changes the distribution of genes, but that this is consequence of selection, not a cause: “Organisms ‘struggle’ as agents or efficient causes; their ‘reward’ may be measured by greater representation of their genes, or material legacies, in future generations. Genes represent the product, not the agent - the stuff of continuity, not the cause of throughput.” [pg. 627] For Gould, genes evidently don’t do anything; they’re just along for the ride. They are “products,” not “agents.” One cannot help wondering where he has been the last few decades. [...]

Я не очень понимаю, что здесь происходит. И Гулд, и те социобиологи, к-х он критикуют, кажется, имеют в виду одну и ту же картину событий. У организмов есть ДНК, в которых хранятся гены. Гены определяют развитие и общую схему функционирования организма. Гены подвергаются случайным мутациям во время репликации; эти мутации влияют на развитие организма; в результате естественного отбора некоторые мутировавшие организмы выживают и размножаются лучше других, тем самым закрепляя мутации в их генах, посылая их в будущие поколения.

Где в этой картине есть место для разногласия и что это значит, собственно, установить, что ген, а не организм, является "единицей отбора", unit of selection? Не понимаю.