  We show that the observed fluxes, spectra and sky distributions of the high
energy diffuse backgrounds of astronomical neutrinos, gamma rays and cosmic ray
positrons satisfy simple relations expected from their common production in
hadronic collisions of high energy cosmic rays (CRs) with diffuse matter. This
provides compelling evidence that the high energy neutrino, gamma ray, and
positron backgrounds have a common origin - hadronic meson production by cosmic
rays in our Galaxy and in external galaxies rather than through the
decay/annihilation of dark matter particles.
