that the relationship between the two rheas was a signal of deeper meaning. It was one of the most crucial of the 'certain facts in the distribution of the inhabitants of South America' cited in the first sentence of Origin , p. 1 , which led to his theory of evolution. As so often when on his own, in the last pages of the notebook Darwin waxed lyrical as he reflected, on p. 87a, 'how many hundred years has been. how many will be...sublime view fine colour of rocks'. This reflection was expanded in his Beagle diary to 'All is stillness & desolation. One reflects how many centuries is has thus been & how many more it will thus remain.- Yet in this scence without one bright object, there is high pleasure, which I can neither explain or comprehend. -- ', p. 209 . Finally this became in Journal of researches 'One reflected how many ages the plain had thus lasted, and how many more it was doomed thus to continue.', p. 198 .