Can Life Experience Change the Mutations of Offspring? Lamarck's Question Revisited Link by Link

Can what an organism does during its life — its food, exercise, behaviour — and the environment it lives in change what its descendants inherit? This paper is part of the BILM programme (Bioelectric Integrity of Living Matter). Our position: variation may be triggered by an organism's life experience acting through its own chemistry, and by the environment acting through its chemistry and physical conditions (temperature, irradiation); these influences leave marks and give rise to changes in the hereditary record, which is the material of evolution; like all new changes, they are more often harmful or neutral, and selection retains only a rare few. The changes have a pattern of sites: it determines where, and of what kind, a change is more likely, but not what new outcome will come of it. The position is divided into five links, each checked against the literature: (1) experience and environment alter the organism's chemistry — measured in humans and animals; (2) this chemistry reaches the germ cells — measured in mice (the father's diet and training alter the small RNAs and marks of spermatozoa and affect the offspring); (3) the number, composition and site of hereditary changes vary — measured mainly for damaging influences; the germline is, on the available evidence, generally well protected, and parental age explains more of the differences between children than anything else; (4) whether changes arise where the organism has worked — open; (5) what remains in the lineage is decided by selection and chance — generally accepted. Where the data admit two readings, both are named together with the fact that would decide between them. Status: links 1, 2 and 5 are established; link 3 is established mainly for damage; link 4 is neither shown nor refuted. Not claimed: transmission of a trained ability through the hereditary record, or changes arising where they would be useful — neither has been shown in the literature. Relation to the BILM programme and disclosure. The programme proposes one formulation of life: the self-replication of systems, each of which maintains its own biological voltage — a paid ion difference on its closed boundary (lineages copy themselves; units hold the voltage). This paper covers the link "experience → variation". Companion papers: What Is the Self? A Bioelectric Definition from Bacteria to Humans (10.5281/zenodo.21779503); Self-Replication as the Precondition of Evolution; The Evolution of Multicellularity (10.5281/zenodo.21772046); Origin of Life: Five Steps from Chemistry to the First Cell (10.5281/zenodo.21761285); the main paper of the programme — What Is Life? A Testable Definition (10.5281/zenodo.21779018). A non-peer-reviewed preprint by the author. Literature searches, source checks and critical review were carried out with the AI assistant Claude (Anthropic) under the author's direction; AI tools also helped to draft the text and to translate it into English (the author checked it and is responsible for the content). The working correspondence is available on request. The work was carried out without external funding, at the author's own expense; there are no competing interests.