  We show that every essentially small finitely semisimple k-linear additive
spherical category in which k=End(1) is a field, is equivalent to its dual over
the long canonical forgetful functor. This includes the special case of modular
categories. In order to prove this result, we show that the universal coend of
the spherical category with respect to the long forgetful functor is self-dual
as a Weak Hopf Algebra.
