t 
PAN- 
AMERICAN GEOLOGIST 
VoL. XXXVII February, 1922' No. 1 
THREE GRAND DISCOVERIES OF LIFE^ 
By Charles Keyes 
With that recent astonishingly deep lowering of life’s record 
in the geological column biotic evolution takes on new aspect. 
Sudden bursting forth, at the beginning of Cambric time, of all 
of the main organic types now living finds ample explanation 
in potential rather than real appearances. Beginnings of organic 
being are pushed, immeasurably back into the abyss of time. 
In the consideration of evolutionary problems popular fancy 
dwells most appealingly upon the unearthing of missing links. 
Each personal interest oftenest focuses fondly upon the possible 
bridging of the chasm between man and monkey. Spectacular 
indeed this is; but it has little attraction for those best equipped 
to accomplish it. Biologically relative small importance attaches 
to this hypothetical man-ape. His one-time existence is now taken 
for granted, with faint curiosity aroused actually to dislodge him 
from under the dusts of the milleniums. 
It is the fundamental changes which life undergoes in the 
course of time that are most illuminating and most sought. In 
viewing life’s trek through the ages many are the missing links 
to be brought to sky. There are many gaps far more difficult to 
span than any of those near man. There are grave crises in 
organic expansion wherein growth and change are greater in short 
1 Paper read before the Geological Society of America, Amherst Meeting, December 
28, 1921, under a somewhat different title. 
1 
