Evolution in Four Dimensions

Jablonka and Lamb argue that inheritance operates through four channels, not one: genetic, epigenetic, behavioural, and symbolic. Each system has its own rules of variation and transmission, and they interact in ways that the gene-centred Modern Synthesis never accounted for. Epigenetic inheritance -- heritable changes in gene expression without changes to DNA sequence -- is now an established field, vindicating much of what the authors proposed. The symbolic dimension, unique to humans, is where cultural evolution theory meets biology most directly. This is the updated biology that almost nobody outside specialist circles cites yet, but which reshapes how we should think about what gets inherited and how change propagates through populations.