P685:3, 60:1.1 The erosion deposits of this period were mostly
conglomerates, shale, and sandstone. The gypsum and red layers throughout these
sedimentations over both America and Europe indicate that the climate of these
continents was arid. These arid districts were subjected to great erosion from
the violent and periodic cloudbursts on the surrounding highlands.
P685:4, 60:1.2 Few fossils are to be found in these layers, but
numerous sandstone footprints of the land reptiles may be observed. In many
regions the one thousand feet of red sandstone deposit of this period contains
no fossils. The life of land animals was continuous only in certain parts of
Africa.
P685:5, 60:1.3 These deposits vary in thickness from 3,000 to
10,000 feet, even being 18,000 on the Pacific coast. Lava was later forced in
between many of these layers. The Palisades of the Hudson River were formed by
the extrusion of basalt lava between these Triassic strata. Volcanic action was
extensive in different parts of the world.
P685:6, 60:1.4 Over Europe, especially Germany and Russia, may
be found deposits of this period. In England the New Red Sandstone belongs to
this epoch. Limestone was laid down in the Southern Alps as the result of a sea
invasion and may now be seen as the peculiar dolomite limestone walls, peaks,
and pillars of those regions. This layer is to be found all over Africa and
Australia. The Carrara marble comes from such modified limestone. Nothing of
this period will be found in the southern regions of South America as that part
of the continent remained down and hence presents only a water or marine deposit
continuous with the preceding and succeeding epochs.
P686:1, 60:1.5 150,000,000 years ago the early land-life
periods of the world's history began. Life, in general, did not fare well but
did better than at the strenuous and hostile close of the marine-life era.
P686:2, 60:1.6 As this era opens, the eastern and central parts
of North America, the northern half of South America, most of Europe, and all of
Asia are well above water. North America for the first time is geographically
isolated, but not for long as the Bering Strait land bridge soon again emerges,
connecting the continent with Asia.
P686:3, 60:1.7 Great troughs developed in North America,
paralleling the Atlantic and Pacific coasts. The great eastern- Connecticut
fault appeared, one side eventually sinking two miles. Many of these North
American troughs were later filled with erosion deposits, as also were many of
the basins of the fresh- and salt-water lakes of the mountain regions. Later on,
these filled land depressions were greatly elevated by lava flows that occurred
underground. The petrified forests of many regions belong to this epoch.
P686:4, 60:1.8 The Pacific coast, usually above water during
the continental submergences, went down excepting the southern part of
California and a large island which then existed in what is now the Pacific
Ocean. This ancient California Sea was rich in marine life and extended eastward
to connect with the old sea basin of the midwestern region.
P686:5, 60:1.9 140,000,000 years ago, suddenly and
with only the hint of the two pre-reptilian ancestors that developed in Africa
during the preceding epoch, the reptiles appeared in full-fledged form. They
developed rapidly, soon yielding crocodiles, scaled reptiles, and eventually
both sea serpents and flying reptiles. Their transition ancestors speedily
disappeared.
P686:6, 60:1.10 These rapidly evolving reptilian dinosaurs soon
became the monarchs of this age. They were egg layers and are distinguished from
all animals by their small brains, having brains weighing less than one pound to
control bodies later weighing as much as forty tons. But earlier reptiles were
smaller, carnivorous, and walked kangaroo-like on their hind legs. They had
hollow avian bones and subsequently developed only three toes on their hind
feet, and many of their fossil footprints have been mistaken for those of giant
birds. Later on, the herbivorous dinosaurs evolved. They walked on all fours,
and one branch of this group developed a protective armor.
P686:7, 60:1.11 Several million years later the first mammals
appeared. They were non-placental and proved a speedy failure; none survived.
This was an experimental effort to improve mammalian types, but it did not
succeed on Earth.
P686:8, 60:1.12 The marine life of this period was meager but
improved rapidly with the new invasion of the sea, which again produced
extensive coast lines of shallow waters. Since there was more shallow water
around Europe and Asia, the richest fossil beds are to be found about these
continents. Today, if you would study the life of this age, examine the
Himalayan, Siberian, and Mediterranean regions, as well as India and the islands
of the southern Pacific basin. A prominent feature of the marine life was the
presence of hosts of the beautiful ammonites, whose fossil remains are found all
over the world.
P686:9, 60:1.13 130,000,000 years ago the seas had changed very little. Siberia and North America were connected by the Bering Strait land bridge. A rich and unique marine life appeared on the Californian Pacific coast, where over one thousand species of ammonites developed from the higher types of cephalopods. The life changes of this period were indeed revolutionary notwithstanding that they were transitional and gradual.
P686:10, 60:1.14 This period extended over twenty-five million years and is known as the Triassic.
P687:1, 60:2.1 120,000,000 years ago a new phase of the
reptilian age began. The great event of this period was the evolution and
decline of the dinosaurs. Land-animal life reached its greatest development, in
point of size, and had virtually perished from the face of the earth by the end
of this age. The dinosaurs evolved in all sizes from a species less than two
feet long up to the huge non-carnivorous dinosaurs, seventy-five feet long, that
have never since been equaled in bulk by any living creature.
P687:2, 60:2.2 The largest of the dinosaurs originated in
western North America. These monstrous reptiles are buried throughout the Rocky
Mountain regions, along the whole of the Atlantic coast of North America, over
Western Europe, South Africa, and India, but not in Australia.
P687:3, 60:2.3 These massive creatures became less active and
strong as they grew larger and larger; but they required such an enormous amount
of food and the land was so overrun by them that they literally starved to death
and became extinct -- they lacked the intelligence to cope with the situation.
P687:4, 60:2.4 By this time most of the eastern part of North
America, which had long been elevated, had been leveled down and washed into the
Atlantic Ocean so that the coast extended several hundred miles farther out than
now. The western part of the continent was still up, but both the northern sea
and the Pacific, which extended eastward to the Dakota Black Hills region, later
invaded even these regions.
P687:5, 60:2.5 This was a fresh-water age characterized by many
inland lakes, as is shown by the abundant fresh-water fossils of the so-called
Morrison beds of Colorado, Montana, and Wyoming. The thickness of these combined
salt- and fresh-water deposits varies from 2,000 to 5,000 feet; but very little
limestone is present in these layers.
P687:6, 60:2.6 The same polar sea that extended so far down
over North America likewise covered all of South America except the soon
appearing Andes Mountains. Most of China and Russia was inundated, but the water
invasion was greatest in Europe. It was during this submergence that the
beautiful lithographic stone of southern Germany was laid down, those strata in
which fossils, such as the most delicate wings of olden insects, are preserved
as of but yesterday.
P687:7, 60:2.7 The flora of this age was much like that of the
preceding. Ferns persisted, while conifers and pines became more and more like
the present-day varieties. Some coal was still being formed along the northern
Mediterranean shores.
P687:8, 60:2.8 The return of the seas improved the weather.
Corals spread to European waters, testifying that the climate was still mild and
even, but they never again appeared in the slowly cooling polar seas. The marine
life of these times improved and developed greatly, especially in European
waters. Both corals and crinoids temporarily appeared in larger numbers than
heretofore, but the ammonites dominated the invertebrate life of the oceans,
their average size ranging from three to four inches, though one species
attained a diameter of eight feet. Sponges were everywhere, and both cuttlefish
and oysters continued to evolve.
P688:1, 60:2.9 110,000,000 years ago the potentials of
marine life were continuing to unfold. The sea urchin was one of the outstanding
mutations of this epoch. Crabs, lobsters, and the modern types of crustaceans
matured. Marked changes occurred in the fish family, a sturgeon type first
appearing, but the ferocious sea serpents, descended from the land reptiles,
still infested all the seas, and they threatened the destruction of the entire
fish family.
P688:2, 60:2.10 This continued to be, pre-eminently, the age of
the dinosaurs. They so overran the land that two species had taken to the water
for sustenance during the preceding period of sea encroachment. These sea
serpents represent a backward step in evolution. While some new species are
progressing, certain strains remain stationary and others gravitate backward,
reverting to a former state. And this is what happened when these two types of
reptiles forsook the land.
P688:3, 60:2.11 As time passed, the sea serpents grew to such
size that they became very sluggish and eventually perished because they did not
have brains large enough to afford protection for their immense bodies. Their
brains weighed less than two ounces notwithstanding the fact that these huge
ichthyosaurs sometimes grew to be fifty feet long, the majority being over
thirty-five feet in length. The marine crocodilians were also a reversion from
the land type of reptile, but unlike the sea serpents, these animals always
returned to the land to lay their eggs.
P688:4, 60:2.12 Soon after two species of dinosaurs migrated to
the water in a futile attempt at self-preservation, two other types were driven
to the air by the bitter competition of life on land. But these flying
pterosaurs were not the ancestors of the true birds of subsequent ages. They
evolved from the hollow-boned leaping dinosaurs, and their wings were of
bat-like formation with a spread of twenty to twenty-five feet. These ancient
flying reptiles grew to be ten feet long, and they had separable jaws much like
those of modern snakes. For a time these flying reptiles appeared to be a
success, but they failed to evolve along lines that would enable them to survive
as air navigators. They represent the non-surviving strains of bird ancestry.
P688:5, 60:2.13 Turtles increased during this period, first
appearing in North America. Their ancestors came over from Asia by way of the
northern land bridge.
P688:6, 60:2.14 One hundred million years ago the reptilian age was drawing to a close. The dinosaurs, for all their enormous mass, were all but brainless animals, lacking the intelligence to provide sufficient food to nourish such enormous bodies. And so did these sluggish land reptiles perish in ever-increasing numbers. Henceforth, evolution will follow the growth of brains, not physical bulk, and the development of brains will characterize each succeeding epoch of animal evolution and planetary progress.
P688:7, 60:2.15 This period, embracing the height and the beginning decline of the reptiles, extended nearly twenty-five million years and is known as the Jurassic.
P688:8, 60:3.1 The great Cretaceous period derives its name
from the predominance of the prolific chalk-making foraminifers in the seas.
This period brings Earth to near the end of the long reptilian dominance and
witnesses the appearance of flowering plants and bird life on land. These are
also the times of the termination of the westward and southward drift of the
continents, accompanied by tremendous crustal deformations and concomitant
widespread lava flows and great volcanic activities.
P689:1, 60:3.2 Near the close of the preceding geologic period
much of the continental land was up above water, although as yet there were no
mountain peaks. But as the continental land drift continued, it met with the
first great obstruction on the deep floor of the Pacific. This contention of
geologic forces gave impetus to the formation of the whole vast north and south
mountain range extending from Alaska down through Mexico to Cape Horn.
P689:2, 60:3.3 This period thus becomes the modern
mountain-building stage of geologic history. Prior to this time there were
few mountain peaks, merely elevated land ridges of great width. Now the Pacific
coast range was beginning to elevate, but it was located seven hundred miles
west of the present shoreline. The Sierras were beginning to form, their
gold-bearing quartz strata being the product of lava flows of this epoch. In the
eastern part of North America, Atlantic sea pressure was also working to cause
land elevation.
P689:3, 60:3.4 100,000,000 years ago the North American continent and a part of Europe were well above water. The warping of the American continents continued, resulting in the metamorphosing of the South American Andes and in the gradual elevation of the western plains of North America. Most of Mexico sank beneath the sea, and the southern Atlantic encroached on the eastern coast of South America, eventually reaching the present shoreline. The Atlantic and Indian Oceans were then about as they are today.
P689:4, 60:3.5 95,000,000 years ago the American and
European land masses again began to sink. The southern seas commenced the
invasion of North America and gradually extended northward to connect with the
Arctic Ocean, constituting the second greatest submergence of the continent.
When this sea finally withdrew, it left the continent about as it now is. Before
this great submergence began, the eastern Appalachian highlands had been almost
completely worn down to the water's level. The many colored layers of pure clay
now used for the manufacture of earthenware were laid down over the Atlantic
coast regions during this age, their average thickness being about 2,000 feet.
P689:5, 60:3.6 Great volcanic actions occurred south of the
Alps and along the line of the present California coast-range mountains. The
greatest crustal deformations in millions upon millions of years took place in
Mexico. Great changes also occurred in Europe, Russia, Japan, and southern South
America. The climate became increasingly diversified.
P689:6, 60:3.7 90,000,000 years ago the angiosperms emerged from these early Cretaceous seas and soon overran the continents. These land plants suddenly appeared along with fig trees, magnolias, and tulip trees. Soon after this time fig trees, breadfruit trees, and palms overspread Europe and the western plains of North America. No new land animals appeared.
P689:7, 60:3.8 85,000,000 years ago the Bering Strait
closed, shutting off the cooling waters of the northern seas. Theretofore the
marine life of the Atlantic-Gulf waters and that of the Pacific Ocean had
differed greatly, owing to the temperature variations of these two bodies of
water, which now became uniform.
P690:1, 60:3.10 All over the world these strata are permeated
with chalk, and these layers of porous semi-rock pick up water at upturned
outcrops and convey it downward to furnish the water supply of much of the
earth's present arid regions.
P690:2, 60:3.11 80,000,000 years ago great disturbances occurred in the earth's crust. The western advance of the continental drift was coming to a standstill, and the enormous energy of the sluggish momentum of the hinter continental mass upcrumpled the Pacific shoreline of both North and South America and initiated profound repercussional changes along the Pacific shores of Asia. This circum-pacific land elevation, which culminated in present-day mountain ranges, is more than twenty-five thousand miles long. And the upheavals attendant upon its birth was the greatest surface distortions to take place since life appeared on Earth. The lava flows, both above and below ground, were extensive and widespread.
P690:3, 60:3.12 75,000,000 years ago marks the end of
the continental drift. From Alaska to Cape Horn the long Pacific coast mountain
ranges were completed, but there were as yet few peaks.
P690:4, 60:3.13 The back thrust of the halted continental drift
continued the elevation of the western plains of North America, while in the
east the worn-down Appalachian Mountains of the Atlantic coast region were
projected straight up, with little or no tilting.
P690:5, 60:3.14 70,000,000 years ago the crustal
distortions connected with the maximum elevation of the Rocky Mountain region
took place. A large segment of rock was over thrust fifteen miles at the surface
in British Columbia; here the Cambrian rocks are obliquely thrust out over the
Cretaceous layers. On the eastern slope of the Rocky Mountains, near the
Canadian border, there was another spectacular over thrust; here may be found
the prelife stone layers shoved out over the then recent Cretaceous deposits.
P690:6, 60:3.15 This was an age of volcanic activity all over
the world, giving rise to numerous small isolated volcanic cones. Submarine
volcanoes broke out in the submerged Himalayan region. Much of the rest of Asia,
including Siberia, was also still under water.
P690:7, 60:3.16 65,000,000 years ago there occurred one
of the greatest lava flows of all time. The deposition layers of these and
preceding lava flows are to be found all over the Americas, North and South
Africa, Australia, and parts of Europe.
P690:8, 60:3.17 The land animals were little changed, but
because of greater continental emergence, especially in North America, they
rapidly multiplied. North America was the great field of the land-animal
evolution of these times, most of Europe being under water.
P690:9, 60:3.18 The climate was still warm and uniform. The
arctic regions were enjoying weather much like that of the present climate in
central and southern North America.
P690:10, 60:3.19 Great plant-life evolution was taking place.
Among the land plants the angiosperms predominated, and many present-day trees
first appeared, including beech, birch, oak, walnut, sycamore, maple, and modern
palms. Fruits, grasses, and cereals were abundant, and these seed-bearing
grasses and trees were to the plant world what the ancestors of man were to the
animal world -- they were second in evolutionary importance only to the
appearance of man himself. Suddenly and without previous gradation, the
great family of flowering plants mutated. And this new flora soon overspread the
entire world.
P691:1, 60:3.20 60,000,000 years ago, though the
land reptiles were on the decline, the dinosaurs continued as monarchs of the
land, the lead now being taken by the more agile and active types of the smaller
leaping kangaroo varieties of the carnivorous dinosaurs. But sometime previously
there had appeared new types of the herbivorous dinosaurs, whose rapid increase
was due to the appearance of the grass family of land plants. One of these new
grass-eating dinosaurs was a true quadruped having two horns and a cape-like
shoulder flange. The land type of turtle, twenty feet across, appeared as did
also the modern crocodile and true snakes of the modern type. Great changes were
also occurring among the fishes and other forms of marine life.
P691:2, 60:3.21 The wading and swimming pre-birds of earlier
ages had not been a success in the air, nor had the flying dinosaurs. They were
a short-lived species, soon becoming extinct. They, too, were subject to the
dinosaur doom, destruction, because of having too little brain substance in
comparison with body size. This second attempt to produce animals that could
navigate the atmosphere failed, as did the abortive attempt to produce mammals
during this and a preceding age.
P691:3, 60:3.22 55,000,000 years ago the evolutionary march was marked by the sudden appearance of the first of the true birds, a small pigeon-like creature which was the ancestor of all bird life. This was the third type of flying creature to appear on earth, and it sprang directly from the reptilian group, not from the contemporary flying dinosaurs or from the earlier types of toothed land birds. And so this becomes known as the age of birds as well as the declining age of reptiles.
P691:4, 60:4.1 The great Cretaceous period was drawing to a
close, and its termination marks the end of the great sea invasions of the
continents. Particularly is this true of North America, where there had been
just twenty-four great inundations. And though there were subsequent minor
submergences, none of these can be compared with the extensive and lengthy
marine invasions of this and previous ages. These alternate periods of land and
sea dominance have occurred in million-year cycles. There has been an agelong
rhythm associated with this rise and fall of ocean floor and continental land
levels. And these same rhythmical crustal movements will continue from this time
on throughout the earth's history but with diminishing frequency and extent.
P691:5, 60:4.2 This period also witnesses the end of the
continental drift and the building of the modern mountains of Urantia. But the
pressure of the continental masses and the thwarted momentum of their agelong
drift are not the exclusive influences in mountain building. The chief and
underlying factor in determining the location of a mountain range is the
pre-existent lowland, or trough, which has become filled up with the
comparatively lighter deposits of the land erosion and marine drifts of the
preceding ages. These lighter areas of land are sometimes 15,000 to 20,000 feet
thick; therefore, when the crust is subjected to pressure from any cause, these
lighter areas are the first to crumple up, fold, and rise upward to afford
compensatory adjustment for the contending and conflicting forces and pressures
at work in the earth's crust or underneath the crust. Sometimes these up thrusts
of land occur without folding. But in connection with the rise of the Rocky
Mountains, great folding and tilting occurred, coupled with enormous over
thrusts of the various layers, both underground and at the surface.
P692:1, 60:4.3 The oldest mountains of the world are located in
Asia, Greenland, and northern Europe among those of the older east-west systems.
The mid-age mountains are in the circum-pacific group and in the second European
east-west system, which was born at about the same time. This gigantic uprising
is almost ten thousand miles long, extending from Europe over into the West
Indies land elevations. The youngest mountains are in the Rocky Mountain system,
where, for ages, land elevations had occurred only to be successively covered by
the sea, though some of the higher lands remained as islands. Subsequent to the
formation of the mid-age mountains, a real mountain highland was elevated which
was destined, subsequently, to be carved into the present Rocky Mountains by the
combined artistry of nature's elements.
P692:2, 60:4.4 The present North American Rocky Mountain region
is not the original elevation of land; that elevation had been long since
leveled by erosion and then re-elevated. The present front range of mountains is
what is left of the remains of the original range that was re-elevated. Pikes
Peak and Longs Peak are outstanding examples of this mountain activity,
extending over two or more generations of mountain lives. These two peaks held
their heads above water during several of the preceding inundations.
P692:3, 60:4.5 Biologically as well as geologically this was an
eventful and active age on land and under water. Sea urchins increased while
corals and crinoids decreased. The ammonites, of preponderant influence during a
previous age, also rapidly declined. On land pine and other modern trees,
including the gigantic redwoods, largely replaced the fern forests. By the end
of this period, while the placental mammal has not yet evolved, the biologic
stage is fully set for the appearance, in a subsequent age, of the early
ancestors of the future mammalian types.
P692:4, 60:4.6 And thus ends a long era of world evolution, extending from the early appearance of land life down to the more recent times of the immediate ancestors of the human species and its collateral branches. This, the Cretaceous age, covers fifty million years and brings to a close the pre-mammalian era of land life, which extends over a period of one hundred million years and is known as the Mesozoic.