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Williams |
But once discovered,
William Smith's unique facts as to the succession of forms in the rocks
would not down. There was one most vital point, however, regarding which
the inferences that seem to follow from these facts needed verification
- the question, namely, whether the disappearance of a fauna from the register
in the rocks really implies the extinction of that fauna. Everything really
depended upon the answer to that question, and none but an accomplished
naturalist could answer it with authority. Fortunately, the most authoritative
naturalist of the time, George Cuvier, took the question in hand - not,
indeed, with the idea of verifying any suggestion of Smith's, but in the
course of his own original studies - at the very beginning of the century,
when Smith's views were attracting general attention.
Cuvier and Smith were exact contemporaries,
both men having been born in 1769, that "fertile year" which gave the world
also Chateaubriand, Von Humboldt, Wellington, and Napoleon. But the French
naturalist was of very different antecedents from the English surveyor.
He was brilliantly educated, had early gained recognition as a scientist,
and while yet a young man had come to be known as the foremost comparative
anatomist of his time. It was the anatomical studies that led him into
the realm of fossils. Some bones dug out of the rocks by workmen in a quarry
were brought to his notice, and at once his trained eye told him that they
were different from anything he had seen before. Hitherto such bones, when
not entirely ignored, had been for the most part ascribed to giants of
former days, or even to fallen angels. Cuvier soon showed that neither
giants nor angels were in question, but elephants of an unrecognized species.
Continuing his studies, particularly with material gathered from gypsum
beds near Paris, he had accumulated, by the beginning of the nineteenth
century, bones of about twenty-five species of animals that he believed
to be different from any now living on the globe.
The fame of these studies went abroad,
and presently fossil bones poured in from all sides, and Cuvier's conviction
that extinct forms of animals are represented among the fossils was sustained
by the evidence of many strange and anomalous forms, some of them of gigantic
size. In 1816 the famous Ossements Fossiles, describing these novel objects,
was published, and vertebrate paleontology became a science. Among other
things of great popular interest the book contained the first authoritative
description of the hairy elephant, named by Cuvier the mammoth, the remains
of which bad been found embedded in a mass of ice in Siberia in 1802, so
wonderfully preserved that the dogs of the Tungusian fishermen actually
ate its flesh. Bones of the same species had been found in Siberia several
years before by the naturalist Pallas, who had also found the carcass of
a rhinoceros
there, frozen in a mud-bank; but no one then suspected that these were
members of an extinct population - they were supposed to be merely transported
relics of the flood.
Cuvier, on the other hand, asserted that
these and the other creatures he described had lived and died in the region
where their remains were found, and that most of them have no living representatives
upon the globe. This, to be sure, was nothing more than William Smith had
tried all along to establish regarding lower forms of life; but flesh and
blood monsters appeal to the imagination in a way quite beyond the power
of mere shells; so the announcement of Cuvier's discoveries aroused the
interest of the entire world, and the Ossements Fossiles was accorded a
popular reception seldom given a work of technical science - a reception
in which the enthusiastic approval of progressive geologists was mingled
with the bitter protests of the conservatives.
"Naturalists certainly have neither
explored all the continents," said Cuvier, "nor do they as yet even know
all the quadrupeds of those parts which have been explored. New species
of this class are discovered from time to time; and those who have not
examined with attention all the circumstances belonging to these discoveries
may allege also that the unknown quadrupeds, whose fossil bones have been
found in the strata of the earth, have hitherto remained concealed in some
islands not yet discovered by navigators, or in some of the vast deserts
which occupy the middle of Africa, Asia, the two Americas, and New Holland.
"But if we carefully attend to the kind
of quadrupeds that have been recently discovered, and to the circumstances
of their discovery, we shall easily perceive that there is very little
chance indeed of our ever finding alive those which have only been seen
in a fossil state.
"Islands of moderate size, and at a considerable
distance from the large continents, have very few quadrupeds. These must
have been carried to them from other countries. Cook and Bougainville found
no other quadrupeds besides hogs and dogs in the South Sea Islands; and
the largest quadruped of the West India Islands, when first discovered,
was the agouti, a species of the cavy, an animal apparently between the
rat and the rabbit.
"It is true that the great continents,
as Asia, Africa, the two Americas, and New Holland, have large quadrupeds,
and, generally speaking, contain species common to each; insomuch, that
upon discovering countries which are isolated from the rest of the world,
the animals they contain of the class of quadruped were found entirely
different from those which existed in other countries. Thus, when the Spaniards
first penetrated into South America, they did not find it to contain a
single quadruped exactly the same with those of Europe, Asia, and Africa.
The puma, the jaguar, the tapir, the capybara, the llama, or glama, and
vicuna, and the whole tribe of sapajous, were to them entirely new animals,
of which they had not the smallest idea....
"If there still remained any great continent
to be discovered, we might perhaps expect to be made acquainted with new
species of large quadrupeds, among which some might be found more or less
similar to those of which we find the exuviae in the bowels of the earth.
But it is merely sufficient to glance the eye over the maps of the world
and observe the innumerable directions in which navigators have traversed
the ocean, in order to be satisfied that there does not remain any large
land to be discovered, unless it may be situated towards the Antarctic
Pole, where eternal ice necessarily forbids the existence of animal life."[1]
Cuvier then points out that the ancients
were well acquainted with practically all the animals on the continents
of Europe, Asia, and Africa now known to scientists. He finds little grounds,
therefore, for belief in the theory that at one time there were monstrous
animals on the earth which it was necessary to destroy in order that the
present fauna and men might flourish. After reviewing these theories and
beliefs in detail, he takes up his Inquiry Respecting the Fabulous Animals
of the Ancients. "It is easy," he says, "to reply to the foregoing objections,
by examining the descriptions that are left us by the ancients of those
unknown animals, and by inquiring into their origins. Now that the greater
number of these animals have an origin, the descriptions given of them
bear the most unequivocal marks; as in almost all of them we see merely
the different parts of known animals united by an unbridled imagination,
and in contradiction to every established law of nature."[2]
Having shown how the fabulous monsters
of ancient times and of foreign nations, such as the Chinese, were simply
products of the imagination, having no prototypes in nature, Cuvier takes
up the consideration of the difficulty of distinguishing the fossil bones
of quadrupeds.
We shall have occasion to revert to this
part of Cuvier's paper in another connection. Here it suffices to pass
at once to the final conclusion that the fossil bones in question are the
remains of an extinct fauna, the like of which has no present-day representation
on the earth. Whatever its implications, this conclusion now seemed to
Cuvier to be fully established.
In England the interest thus aroused was
sent to fever-heat in 1821 by the discovery of abundant beds of fossil
bones in the stalagmite-covered floor of a cave at Kirkdale, Yorkshire
which went to show that England, too, had once had her share of gigantic
beasts. Dr. Buckland, the incumbent of the chair of geology at Oxford,
and the most authoritative English geologist of his day, took these finds
in hand and showed that the bones belonged to a number of species, including
such alien forms as elephants, rhinoceroses, hippopotami, and hyenas. He
maintained that all of these creatures had actually lived in Britain, and
that the caves in which their bones were found had been the dens of hyenas.
The claim was hotly disputed, as a matter
of course. As late as 1827 books were published denouncing Buckland, doctor
of divinity though he was, as one who had joined in an "unhallowed cause,"
and reiterating the old cry that the fossils were only remains of tropical
species washed thither by the deluge. That they were found in solid rocks
or in caves offered no difficulty, at least not to the fertile imagination
of Granville Penn, the leader of the conservatives, who clung to the old
idea of Woodward and Cattcut that the deluge had dissolved the entire crust
of the earth to a paste, into which the relics now called fossils had settled.
The caves, said Mr. Penn, are merely the result of gases given off by the
carcasses during decomposition - great air-bubbles, so to speak, in the
pasty mass, becoming caverns when the waters receded and the paste hardened
to rocky consistency.
But these and such-like fanciful views
were doomed even in the day of their utterance. Already in 1823 other gigantic
creatures, christened ichthyosaurus and plesiosaurus by Conybeare, had
been found in deeper strata of British rocks; and these, as well as other
monsters whose remains were unearthed in various parts of the world, bore
such strange forms that even the most sceptical could scarcely hope to
find their counterparts among living creatures. Cuvier's contention that
all the larger vertebrates of the existing age are known to naturalists
was borne out by recent explorations, and there seemed no refuge from the
conclusion that the fossil records tell of populations actually extinct.
But if this were admitted, then Smith's view that there have been successive
rotations of population could no longer be denied. Nor could it be in doubt
that the successive faunas, whose individual remains have been preserved
in myriads, representing extinct species by thousands and tens of thousands,
must have required vast periods of time for the production and growth of
their countless generations.
As these facts came to be generally known,
and as it came to be understood in addition that the very matrix of the
rock in which fossils are imbedded is in many cases one gigantic fossil,
composed of the remains of microscopic forms of life, common-sense, which,
after all, is the final tribunal, came to the aid of belabored science.
It was conceded that the only tenable interpretation of the record in the
rocks is that numerous populations of creatures, distinct from one another
and from present forms, have risen and passed away; and that the geologic
ages in which these creatures lived were of inconceivable length. The rank
and file came thus, with the aid of fossil records, to realize the import
of an idea which James Hutton, and here and there another thinker, had
conceived with the swift intuition of genius long before the science of
paleontology came into existence. The Huttonian proposition that time is
long had been abundantly established, and by about the close of the first
third of the last century geologists had begun to speak of "ages" and "untold
aeons of time" with a familiarity which their predecessors had reserved
for days and decades. |
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