Raven mad

I need help. Birdwatching readers of this blog, don't be deterred by the poetry talk that follows - you have a role to play. And poetry-loving readers, don't let the birds put you off. You might hold the key to a minor mystery too.

I'm usually pretty good at making notes for poems. I sometimes scribble them on the backs of receipts or bus tickets, or use the notebook on my phone, but I've generally got at least one real notebook on me, and I have a sort of 'master' journal into which I transfer everything at the first opportunity.

I'm usually good, too (and this is the journo in me) at attributing all the material appropriately. Which is to say, if there's no indication otherwise, I assume that the note is my own original work. If it's something I've heard or overheard or read, and noted down for later use (either as inspiration or as background material), then I also make a note of exactly where it came from.

Earlier this week, I was reading through some notes for a barely-started poem involving ravens. I must have been writing them in a rush, because none of the notes are attributed to anyone else, despite the fact that I straight away recognised one bit of background material, discussing the fact that ravens are known to engage in purely recreational 'play', as being from Mark Cocker's Birds Britannica (a book I'll never get tired of recommending to anyone who'll listen).

The next note, also unattributed, reads: "Quite why this [the propensity for play] should have made them thought suitable as messengers of the divine, or even deities themselves, is not clear. No one needs a god who's taking the piss the moment your back is turned."

That's not from Mark's book, but I certainly didn't write it either. So who did? Does anyone recognise it at all? I'd love to know just to be able to read it in context again. Your suggestions please, because I've been trying to work it out for two days now and it's beginning to drive me round the bend.