I
Bergson, the new French philosopher, thinks we all had a narrow
escape, back in geologic time, of having our eggs spoiled before
they were hatched, or, rather, rendered incapable of hatching by too
thick a shell. This was owing to the voracity of the early
organisms. As they became more and more mobile, they began to take
on thick armors and breastplates and shells and calcareous skins to
protect themselves from one another. This tendency resulted, he
thinks, in the arrest of the entire animal world in its evolution
toward higher and higher forms. These shells and armors begat a kind
of torpor and immobility which has continued down to our day with
the echinoderms and mollusks, but the arthropods and vertebrates
escaped it by some lucky stroke. Now you and I are here without
imprisoning shells on our backs; but how or why did we escape?
Bergson does not say. Was it a matter of luck or chance? Was there
ever a time when the stream of life tended to harden and become
fixed in its own forms like a stream of cooling lava, or has the
innate plasticity of life been easily equal to its own ends? True,
the clam remains a clam, and the starfish remains a starfish; some
other forms have carried the evolutionary impulse forward till it
flowered in man. Was this impulse ever really checked or endangered?
Was the golden secret ever intrusted to the keeping of any single
form? and, had that form been cut off, would the earth have been
still without its man? These are puzzling questions.
Thus, when we have come to look upon life and nature in the light of
evolution, what vistas are opened to us where before were only blank
walls! The geologic ages take on a new interest to us. We know that
in some form we were even there. The systems of sedimentary rocks
which the geologist portrays, piled one upon the other to a depth of
fifty miles or more, seem like the stairway by which we have
ascended, taking on some new and more developed form at each rise.
What we were at the first step in Cambrian times only the Lord
knows, but whatever we were, we crept up or floated up to the next
rise. In the Silurian seas we may have been a trilobite for aught we
know; at any rate, we were the outcome of the life impulse that
begat the trilobites, but our fate was not bound up with theirs, as
their race came to an end in those early geologic ages, and our stem
form did not. Whether or not we were a fish in the Devonian seas,
there is little doubt that we had gills, because we have the gill
slits yet in our early foetal life, and it is quite certain that in
some way we owe our backbones to the fishes.
When the rocks that form my native Catskills were being laid down in
the Devonian waters, I fancy that my aquatic embryo was swimming
about somewhere and slowly waxing strong. Up and up I climbed across
the sandstone steps, across the limestone, the conglomerate, the
slate, up into Carboniferous times. The upper and nether millstones
of the "millstone grit" did not crush me, neither did the floods and
the convulsions of Carboniferous times that buried the vast
vegetable growths that resulted in our coal measures engulf or
destroy me. About that time probably, I emerged from the water and
became an amphibian, and maybe got my five fingers and five toes on
each side.
Nor did the wholesale destruction of animal life at the end of
Palaeozoic time cut off my line of descent. The monstrous reptiles
of the succeeding or Mesozoic age, the petrified remains of one of
which was recently found in the sandstone rocks near the river's
edge under the Palisades of the Hudson, do not seem to have
endangered the golden thread by which our fate hung. Still "I mount
and mount." The stairs by which I climb were rent by earthquakes and
volcanoes, the strata were squeezed up and overturned and folded in
the great mountain-chains; the Alps, the Andes, the Himalayas, the
Coast Range were born; the earth-throes must have been tremendous at
times; yet I escaped it all. The huge and fearful mammals of the
third or Tertiary period passed me by unharmed. Eruptions and
cataclysms, the sinking of the land, the inundations of the sea,
world-wide deformations of the earth's crust, fire and ice and
floods, monsters of the deep and dragons of the land and the air
have beset my course from the first, and yet here I am, here we all
are, and apparently none the worse for the appalling dangers we have
passed through.
Evolution thus makes the world over for us. It shows us in what a
complex web of vital and far-reaching relations we stand. It gives
us an outlook upon the past that is startling, and in some ways
forbidding, yet one that ought to be stimulating and inspiring. If
we look back with a shudder we should look forward with a thrill. If
the past is terrible, the future is in the same degree cheering and
inviting. If we came out of those lowly and groveling forms, to
what heights of being may we not be carried by the impetus that
brought us thus far? In fact, to what heights has it already carried
us!