The cliffs are called the Heads Of Ayr. I always though these cliffs were called that because it was the largest landmass in close proximity to Ayr, at the head of the toun (town) so to speak. I am now of the notion it's because of the various facial features that can be seen in the cliff face, pardon the pun. This particular face is quite detailed, it has eyes, nose, cheek bones, top and bottom lip, chin, even shoulders etc.
There is another head similar to this one but it did not show up today... he must have went home when he heard I was comin. :) Then just around the corner we have the Lions Head, again difficult to see in this first shot as the lightin has to be just right, but you can almost make out the the Lions head covering the top third of the cliff and a brave hiker walking below.
So there are 3 heads one the cliff that I know of is that where the name derives from? Then again who knows I could be totally wrong? Now you know what pareidolia means or do you :)