reptilians

60:1.1The 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.

60:1.2Few 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.

60:1.3These 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.

60:1.4Over 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.

60:1.5150,000,000 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.

60:1.6As 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.

60:1.7Great 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 which oc­curred un­der­ground. The pet­ri­fied forests of many re­gions be­long to this epoch.

60:1.8The 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.

60:1.9140,000,000 years ago, sud­denly and with only the hint of the two pre­rep­til­ian 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.

60:1.10These 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 kan­ga­roo­like 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.

60:1.11Sev­eral mil­lion years later the first mam­mals ap­peared. They were non­pla­cen­tal and proved a speedy fail­ure; none sur­vived. This was an ex­per­i­men­tal ef­fort to im­prove mam­malian types, but it did not suc­ceed on Uran­tia.

60:1.12The 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.

60:1.13130,000,000 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.

60:1.14This pe­riod ex­tended over twenty-five mil­lion years and is known as the Tri­as­sic.

60:2.1120,000,000 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 non­car­niv­o­rous di­no­saurs, sev­enty-five feet long, that have never since been equaled in bulk by any liv­ing crea­ture.

60:2.2The 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.

60:2.3These 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.

60:2.4By 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 even these re­gions were later in­vaded by both the north­ern sea and the Pa­cific, which ex­tended east­ward to the Dakota Black Hills re­gion.

60:2.5This 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.

60:2.6The 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.

60:2.7The 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.

60:2.8The 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.

60:2.9110,000,000 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.

60:2.10This 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.

60:2.11As 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.

60:2.12Soon 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 bat­like 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 which would en­able them to sur­vive as air nav­i­ga­tors. They rep­re­sent the non­sur­viv­ing strains of bird an­ces­try.

60:2.13Tur­tles in­creased dur­ing this pe­riod, first ap­pear­ing in North Amer­ica. Their an­ces­tors came over from Asia by way of the north­ern land bridge.

60:2.14One 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.

60:2.15This pe­riod, em­brac­ing the height and the be­gin­ning de­cline of the rep­tiles, ex­tended nearly twenty-five mil­lion years and is known as the Juras­sic.

• reptilians

60:3.1470,000,000 years ago the crustal dis­tor­tions con­nected with the max­i­mum el­e­va­tion of the Rocky Moun­tain re­gion took place. A large seg­ment of rock was over­thrust 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 over­thrust; here may be found the pre­life stone lay­ers shoved out over the then re­cent Cre­ta­ceous de­posits.

65:2.8The frogs gave rise to the Rep­tilia, a great an­i­mal fam­ily which is vir­tu­ally ex­tinct, but which, be­fore pass­ing out of ex­is­tence, gave ori­gin to the whole bird fam­ily and the nu­mer­ous or­ders of mam­mals.

65:2.9Prob­a­bly the great­est sin­gle leap of all pre­hu­man evo­lu­tion was ex­e­cuted when the rep­tile be­came a bird. The bird types of to­day—ea­gles, ducks, pi­geons, and os­triches—all de­scended from the enor­mous rep­tiles of long, long ago.

65:2.10The king­dom of rep­tiles, de­scended from the frog fam­ily, is to­day rep­re­sented by four sur­viv­ing di­vi­sions: two non­pro­gres­sive, snakes and lizards, to­gether with their cousins, al­li­ga­tors and tur­tles; one par­tially pro­gres­sive, the bird fam­ily, and the fourth, the an­ces­tors of mam­mals and the di­rect line of de­scent of the hu­man species. But though long de­parted, the mas­sive­ness of the pass­ing Rep­tilia found echo in the ele­phant and mastodon, while their pe­cu­liar forms were per­pet­u­ated in the leap­ing kan­ga­roos.

59:6.8Among the land an­i­mals the frogs reached their cli­max in the pre­ced­ing age and rapidly de­clined, but they sur­vived be­cause they could long live even in the dry­ing-up pools and ponds of these far-dis­tant and ex­tremely try­ing times. Dur­ing this de­clin­ing frog age, in Africa, the first step in the evo­lu­tion of the frog into the rep­tile oc­curred. And since the land masses were still con­nected, this pre­rep­til­ian crea­ture, an air breather, spread over all the world. By this time the at­mo­sphere had been so changed that it served ad­mirably to sup­port an­i­mal res­pi­ra­tion. It was soon af­ter the ar­rival of these pre­rep­til­ian frogs that North Amer­ica was tem­porar­ily iso­lated, cut off from Eu­rope, Asia, and South Amer­ica.