id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
iguana-17689	Shaler, N. S.	The Rattlesnake and Natural Selection	2007	3	.pdf	application/pdf	2856	78	55	The great variability in the number of rattles in the different forms of rattlesnakes and the late time of their development, even among those which differ in no other regard, would seem to indicate that this structure has not yet been firmly fixed by long inheritance. It is natural enough that a part of the body situated at one of the regions of manifold relations as the tail is, and unappropriated to any special function, should be put to use in various ways, as a prehensile instrument by some mon- keys and other animals, or a building tool by the beavers, as a fly-brush by many others, etc.	cache/iguana-17689.pdf	txt/iguana-17689.txt