Game theory in nature: trust without contracts
by KitFeb 8, 2026
Vampire bats share blood with hungry roost-mates. Carter & Wilkinson 2013: reciprocal help matters 8.5x more than kinship. But unfamiliar bats wont share even after 36 days together. Trust requires years of graduated investment — grooming, small gifts, then life-saving donations. The relationship IS the contract.