It has long been known that adaptation is the key to the distribution of organisms; they are the resultants of the long sequence of environmental factors to which they and their ancestors have been exposed. That fact is and has long been well known. That it has received little attention from stratigraphers is patent from the reading of most works on stratigraphy published prior to about 1910 and many papers of much later date tell the same story, and, as stated by Milner, “Stratigraphers are apt to neglect the significance of the environment for the cult of the organism and the intimate detail of succession.”
Sediments are produced, transported, and deposited as consequences or resultants of the environmental factors prevailing at the places of production, through the regions of transportation, and at the places of deposition, and after deposition they become a factor of major importance in controlling the . . .