:::Various quotes from the Engel paper might give the general drift. 'electronic energy transfer involving oscillatory populations of donors and acceptors.' 'direct evidence for remarkably long-lived electronic quantum coherence playing an important part in energy transfer.' '...oscillations caused by electronic coherence .... Such quantum coherence, a coherent superposition of electronic states ... is formed when the system is initially excited by a short wave pulse ...' '... theoretical models indicate that electronic coherence should dephase ... in less than 250 fs ... The strong quantum beating that we observe to last for at least 660 fs clearly exceeds the model predictions .... the protein must have a more active role in a reallistic bath model; that it must be allowed to interact with both donors and acceptors, to enable coherence transfer ....'