Dreamer Easy

"Parkinson himself was a palaeontologist, as well as a physician... One wonder whether he may have partly regarded parkinsonism as an atavism, a reversion, the uncovering, through disease, of an ancestral, an 'antediluvian' mode of function dating from the ancient past.

"Whether or not this is so of parkinsonism is arguable, but one can certainly see reversion to, or disclosure of, a variety of primitive behaviours in post-encephalitic syndromes on occasion, and in a rare condition, branchial myoclonus, arising from lesions in the brain stem. Here there occur rhythmic movements of the palate, middle-ear muscles, and certain muscles in the neck - an odd and unintelligible pattern, until one realizes that these are the only vestiges of the gill arches, the branchial musculature, in man. Branchial myoclonus is, in effect, a gill movement in man, a revelation of thefact that we still carry our fishy ancestors, our evolutionary precursors, within us."

- Oliver Sacks, The Island of the Colour-blind