Recent attempts to fit Type Ia supernova data by modeling the dark energy density as a truncated Taylor series have suggested the possibility of metamorphosis , i.e. , a rapidly evolving equation of state parameter , w _ { DE } ( z ) .
However , we show that fits using that parametrization have significant problems .
Evolution of w _ { DE } ( z ) 
is both favoured and in some sense forced , and the equation of state parameter blows up or diverges in large regions of the parameter space .
To further elucidate these problems we have simulated sets of supernova data in a \Lambda –universe to show that the suggested “ evidence ” for metamorphosis is also common for w _ { DE } = -1 .