238 READINGS IN BIOLOGICAL SCIENCE 



the fossilized fragments of man's own frame. But this is otherwise a loose 

 term. What kind of a "man" is meant? 



As an erect animal newly distinct from an ape, with a growing propen- 

 sity to reinforce his hands with rocks and sticks, man is probably older 

 than this, by far. De Terra, it is true, believes that the advent of the ice 

 itself, shifting climatic zones southward in Asia and causing a dispersal of 

 the once flourishing ape family into nev/ and varying environments, was 

 the indirect stimulus to the emergence of man from the anthropoids, so that 

 this event, he thinks, must have happened within the Pleistocene period 

 itself. But many students, Hooton being the most articulate, feel that man 

 must have been evolving for several million years at the end of the pre- 

 ceding Tertiary age, using tools of stone which can not even be recognized 

 to-day before getting to the stage of physique and culture which we see 

 in the earliest known remains. Man's age, in other words, is doubtless sev- 

 eral times as great as the "Age of Man." 



On the other hand, we ourselves, in our present form, constitute one 

 particular and definite species of man, the species Homo sapie?js, which 

 must have arisen later on within this total limit of time. He is an advanced 

 type and is distinct from various other known human forms. However, 

 almost all these forms seem to be well above, and therefore later than, the 

 earUest imaginable stage of true humanity, and all may be thought of as 

 lines, gradually separating, which descended from the original human 

 stem. Homo sapiens appeared somewhere as such a line but how old he 

 is, as a species, we do not know. Curiosity as to his age is not simply the 

 mark of a fond antiquarianism, for information on the pace of recent 

 human development would give us a better perspective for the possibilities 

 of future change in mankind. How old, then, is Homo sapiens? 



We really can not say, taking the remains alone. If we dutifully repeat 

 only what paleontology has revealed so far, it would seem as though Ho?no 

 sapiens were very recent. (Actually, we know somewhat more about the 

 age of our nearest neighbor in time, the species of Neanderthal Man.) 

 There is, however, some imperfect evidence that indicates Hovio sapieiis 

 as being fairly ancient, and there are various abstract considerations and 

 deductions which bear this belief out. 



Put purely in terms of skeletal evidence, this is what we know. /. There 

 is archeological proof of human existence apparently throughout the 

 Pleistocene, running back a milHon years, to use a figure, or 1,000 millen- 

 niums. 2. There are remains of the species Homo sapiens, and Homo sapiejis 

 only, going back some 30 millenniums (more or less, actual dates not being 

 certain) to the Cro Magnons, who appeared at the beginning of the Upper 

 Paleolithic, the last portion of the Old Stone Age. 5. In the previous 950 

 or more millenniums (the disproportionately long Lower Paleolithic, com- 

 prising i%oths of the whole Pleistocene) there were various types of fossil 

 men, but no finds have been made which would prove, with the finality 



