Tao is that ever-present endless point at which yin and yang unite.

Yin acts by virtue of yang and yang acts by virtue of yin. When yin and yang interact that is Tao not yin or yang.

So... What is there without Tao?

There is Tao without yin and without yang, but there can be neither yin nor yang without Tao.

Tao IS creation, dissolution and rebirth. Tao is the created and the creator.