Identifying an Effective Social Norm Message to Strengthen Americans’ Support for Biodiversity Policies

We develop a three-step titration approach to identify effective norm messages for policy change. Across three preregistered studies (n=7,893), we provide first evidence for the titration being effective. The selected message reduces misperceptions (δ=0.81) and boosts support for the US ratifying the Convention on Biodiversity (δ=0.09) and petition signatures (3.30p.p.).