The field's flagship: Dias and Ressler, Nature Neuroscience 2014, conditioned F0 male mice to fear acetophenone, the F1 and F2 generations showing specific startle sensitivity to the same odor, enlarged M71 glomeruli, and hypomethylation at the Olfr151 receptor gene in the fathers' sperm, with IVF and cross-fostering excluding social transmission. The documented critique: Columbia's Timothy Bestor noted the implicated CpG sites sit in the gene body, not the promoter, where methylation does not regulate expression, so the mechanism story has a documented hole even as the behavioral effect replicated. The human cohorts: the Dutch Hunger Winter, 1944-45, famine-exposed fetuses showing altered IGF2 methylation decades later, and their children showing metabolic effects, and the Overkalix records, grandparental food supply correlating with grandchild mortality, the human evidence being real, correlational, and mechanism-poor, exactly the tier the archive files it at.
The folk reading is the rehabilitation: Lamarck, the textbook loser of the inheritance wars, acquired traits do not pass, getting a documented partial pardon, the giraffe's neck staying Darwinian but the wound, the famine, and the fear apparently writing into the germline, the tradition's emotion being generational: the trauma of the grandparents living in the grandchildren's chemistry, the folk and clinical literatures merging on the phrase inherited trauma, which the archive files with the mechanism caveat attached, the expression being social and the methylation being only partly shown. The Nagai butterflies give the tradition its freshest exhibit: the lavender aversion appearing in the offspring of the trained, in a kitchen, observed by a child.
The claim: transgenerational inheritance is the archive's oldest moral doctrine arriving with a p-value, the sins of the fathers visited upon the children unto the third and fourth generation being, in the 2014 paper, the F2 generation, literally the grandchildren, the scripture's arithmetic matching the experiment's, and the archive's note being that the laboratory rediscovered the doctrine by shocking mice, which is either the oldest wisdom confirmed or the oldest horror quantified, depending on whether you read it as warning or as inheritance law. Verdict: the archive's verdict is the field's own restraint plus its own stake: the effect is documented, the mechanism is contested, and the implication is civilization-scale, every famine, war, and poisoning in this archive's files now carrying a documented biological tail two generations long. The grandfather smelled the cherry blossom and was shocked. The grandson flinches at the tree. The erasure system, per Reik, is not fail-safe. Neither, per the archive's whole collection, is anything else. The soup forgets almost everything. The sperm, per the assay, keeps a list. Read it before you sign the next generation's contracts.
If the grandchildren carry the wound's chemistry, what are we inheriting right now, and whose shock was it originally?