  We introduce a simple parametrization of the dark energy equation of state,
\omega, which is motivated from theory and recent experimental data. The theory
is related to the tracker solution to alleviate the fine tuning problem. Recent
experimental data indicates that the present value of \omega is close to -1. We
analyze the evolution of \omega from the separation of CMB peaks and the time
variation of the fine structure constant, \alpha. We find that -1.00 \leq
\omega^{(0)} \leq -0.971_{-0.027}^{+0.017} and 1.76_{-0.42}^{+0.29} \times
10^{-4} \leq (d \omega / dz)_{z=0} \leq 0.041_{-0.037}^{+0.016} at 95%
confidence level (CL).
