31. Why do interventions work across species?

Some interventions work across species because they target conserved mechanisms. However, their effect sizes and tradeoffs depend on species biology: lineage-specific architecture, life history, dominant weak links, cancer control, tissue renewability, and failure thresholds. Conservation explains why similar approaches can be informative across organisms, whereas specific mechanisms explain why the same intervention can have very different magnitudes in worms, mice, dogs, and humans.