  Singular sectors $\mathcal{Z}_{\mathrm{sing}}$ (loci of zeros) for
real-valued non-positively defined partition functions $\mathcal{Z}$ of $n$
variables are studied. It is shown that $\mathcal{Z}_{\mathrm{sing}}$ have a
stratified structure and each stratum is a set of certain hypersurfaces in
$\mathbb{R}^n$. The concept of statistical amoebas is introduced and their
properties are studied. Relation with algebraic amoebas is discussed. Tropical
limit of statistical amoebas is considered too.
