How Humans Detect Genetic Relatives Through Hidden Signals
Humans use multiple biological systems—smell, facial recognition, and childhood proximity—to detect genetic relatives without conscious awareness. The same MHC genes that govern immune function produce unique body odors that help us identify kin and avoid inbreeding. Modern DNA testing and AI facial recognition are now making these invisible processes explicit, creating unprecedented opportunities to find unknown relatives while raising profound questions about privacy, family identity, and t...