It was earlier conjectured by the second and the third authors that any
rational curve g:CP1→CPn such that the inverse
images of all its flattening points lie on the real line RP1⊂CP1 is real algebraic up to a linear fractional transformation of
the image CPn. (By a flattening point p on g we mean a point
at which the Frenet n-frame (g′,g′′,...,g(n)) is degenerate.) Below we
extend this conjecture to the case of meromorphic functions on real algebraic
curves of higher genera and settle it for meromorphic functions of degrees
2,3 and several other cases.Comment: 10 pages, 1 figur