^62:2.2 These dawn mammals attained full growth when 3 or 4 years of age, having a potential life span, on the average, of about 20 years. As a rule offspring were born singly, although twins were occasional.

^62:2.3 The members of this new species had the largest brains for their size of any animal that had theretofore existed on earth. They experienced many of the emotions and shared numerous instincts which later characterized primitive man, being highly curious and exhibiting considerable elation when successful at any undertaking. Food hunger and sex craving were well developed, and a definite sex selection was manifested in a crude form of courtship and choice of mates. They would fight fiercely in defence of their kindred and were quite tender in family associations, possessing a sense of self-abasement bordering on shame and remorse. They were very affectionate and touchingly loyal to their mates, but if circumstances separated them, they would choose new partners.

^62:2.4 Being small of stature and having keen minds to realize the dangers of their forest habitat, they developed an extraordinary fear which led to those wise precautionary measures that so enormously contributed to survival, such as their construction of crude shelters in the high treetops which eliminated many of the perils of ground life. The beginning of the fear tendencies of mankind more specifically dates from these days.

^62:2.5 These dawn mammals developed more of a tribal spirit than had ever been previously exhibited. They were, indeed, highly gregarious but nevertheless exceedingly pugnacious when in any way disturbed in the ordinary pursuit of their routine life, and they displayed fiery tempers when their anger was fully aroused. Their bellicose natures, however, served a good purpose; superior groups did not hesitate to make war on their inferior neighbours, and thus, by selective survival, the species was progressively improved. They very soon dominated the life of the smaller creatures of this region, and very few of the older noncarnivorous monkeylike tribes survived.

^62:2.6 These aggressive little animals multiplied and spread over the Mesopotamian peninsula for more than 1,000 years, constantly improving in physical type and general intelligence. And it was just 70 generations after this new tribe had taken origin from the highest type of lemur ancestor that the next epoch-making development occurred — the sudden differentiation of the ancestors of the next vital step in the evolution of human beings on Urantia.

3. THE MID-MAMMALS

^62:3.1 Early in the career of the dawn mammals, in the treetop abode of a superior pair of these agile creatures, twins were born, one male and one female. Compared with their ancestors, they were really handsome little creatures. They had little hair on their bodies, but this was no disability as they lived in a warm and equable climate.

^62:3.2 These children grew to be a little over 1.2 m in height. They were in every way larger than their parents, having longer legs and shorter arms. They had almost perfectly opposable thumbs, just about as well adapted for diversified work as the present human thumb. They walked upright, having feet almost as well suited for walking as those of the later human races.

^62:3.3 Their brains were inferior to, and smaller than, those of human beings but very superior to, and comparatively much larger than, those of their ancestors. The twins early displayed superior intelligence and were soon recognized as the heads of the whole tribe of dawn mammals, really instituting a primitive form of social organization and a crude economic division of labour. This brother and sister mated and soon enjoyed the society of 21 children much like themselves, all more than 1.2 m tall and in every way superior to the ancestral species. This new group formed the nucleus of the mid-mammals.

^62:3.4 When the numbers of this new and superior group grew great, war, relentless war, broke out; and when the terrible struggle was over, not a single individual of the pre-existent and ancestral race of dawn mammals remained alive. The less numerous but more powerful and intelligent offshoot of the species had survived at the expense of their ancestors.

^62:3.5 And now, for almost 15,000 years (600 generations), this creature became the terror of this part of the world. All of the great and vicious animals of former times had perished. The large beasts native to these regions were not carnivorous, and the larger species of the cat family, lions and tigers, had not yet invaded this peculiarly sheltered nook of the earth’s surface. Therefore did these mid-mammals wax valiant and subdue the whole of their corner of creation.

^62:3.6 ¶ Compared with the ancestral species, the mid-mammals were an improvement in every way. Even their potential life span was longer, being about 25 years. A number of rudimentary human traits appeared in this new species. In addition to the innate propensities exhibited by their ancestors, these mid-mammals were capable of showing disgust in certain repulsive situations. They further possessed a well-defined hoarding instinct; they would hide food for subsequent use and were greatly given to the collection of smooth round pebbles and certain types of round stones suitable for defensive and offensive ammunition.

^62:3.7 These mid-mammals were the first to exhibit a definite construction propensity, as shown in their rivalry in the building of both treetop homes and their many-tunnelled subterranean retreats; they were the first species of mammals ever to provide for safety in both arboreal and underground shelters. They largely forsook the trees as places of abode, living on the ground during the day and sleeping in the treetops at night.

^62:3.8 As time passed, the natural increase in numbers eventually resulted in serious food competition and sex rivalry, all of which culminated in a series of internecine battles that nearly destroyed the entire species. These struggles continued until only one group of less than 100 individuals was left alive. But peace once more prevailed, and this lone surviving tribe built anew its treetop bedrooms and once again resumed a normal and semipeaceful existence.

^62:3.9 ¶ You can hardly realize by what narrow margins your prehuman ancestors missed extinction from time to time. Had the ancestral frog of all humanity jumped 5 cm less on a certain occasion, the whole course of evolution would have been markedly changed. The immediate lemurlike mother of the dawn-mammal species escaped death no less than 5 times by mere hairbreadth margins before she gave birth to the father of the new and higher mammalian order. But the closest call of all was when lightning struck the tree in which the prospective mother of the Primates twins was sleeping. Both of these mid-mammal parents were severely shocked and badly burned; three of their 7 children were killed by this bolt from the skies. These evolving animals were almost superstitious. This couple whose treetop home had been struck were really the leaders of the more progressive group of the mid-mammal species; and following their example, more than half the tribe, embracing the more intelligent families, moved about 3 km away from this locality and began the construction of new treetop abodes and new ground shelters — their transient retreats in time of sudden danger.

^62:3.10 Soon after the completion of their home, this couple, veterans of so many struggles, found themselves the proud parents of twins, the most interesting and important animals ever to have been born into the world up to that time, for they were the first of the new species of Primates constituting the next vital step in prehuman evolution.