^49:3.4 Life on the worlds of the nonbreathers is radically different from what it is on Urantia. The nonbreathers do not eat food or drink water as do the Urantia races. The reactions of the nervous system, the heat-regulating mechanism, and the metabolism of these specialized peoples are radically different from such functions of Urantia mortals. Almost every act of living, aside from reproduction, differs, and even the methods of procreation are somewhat different.

^49:3.5 On the nonbreathing worlds the animal species are radically unlike those found on the atmospheric planets. The nonbreathing plan of life varies from the technique of existence on an atmospheric world; even in survival their peoples differ, being candidates for Spirit fusion. Nevertheless, these beings enjoy life and carry forward the activities of the realm with the same relative trials and joys that are experienced by the mortals living on atmospheric worlds. In mind and character the nonbreathers do not differ from other mortal types.

^49:3.6 You would be more than interested in the planetary conduct of this type of mortal because such a race of beings inhabits a sphere in close proximity to Urantia.

^49:4.1 There are great differences between the mortals of the different worlds, even among those belonging to the same intellectual and physical types, but all mortals of will dignity are erect animals, bipeds.

^49:4.2 There are six basic evolutionary races: three primary — red, yellow, and blue; and three secondary — orange, green, and indigo. Most inhabited worlds have all of these races, but many of the three-brained planets harbour only the three primary types. Some local systems also have only these three races.

^49:4.3 The average special physical-sense endowment of human beings is 12, though the special senses of the three-brained mortals are extended slightly beyond those of the one- and two-brained types; they can see and hear considerably more than the Urantia races.

^49:4.4 Young are usually born singly, multiple births being the exception, and the family life is fairly uniform on all types of planets. Sex equality prevails on all advanced worlds; male and female are equal in mind endowment and spiritual status. We do not regard a planet as having emerged from barbarism so long as one sex seeks to tyrannize over the other. This feature of creature experience is always greatly improved after the arrival of a Material Son and Daughter.

^49:4.5 ¶ Seasons and temperature variations occur on all sunlighted and sun-heated planets. Agriculture is universal on all atmospheric worlds; tilling the soil is the one pursuit that is common to the advancing races of all such planets.

^49:4.6 Mortals all have the same general struggles with microscopic foes in their early days, such as you now experience on Urantia, though perhaps not so extensive. The length of life varies on the different planets from 25 years on the primitive worlds to near 500 on the more advanced and older spheres.

^49:4.7 Human beings are all gregarious, both tribal and racial. These group segregations are inherent in their origin and constitution. Such tendencies can be modified only by advancing civilization and by gradual spiritualization. The social, economic, and governmental problems of the inhabited worlds vary in accordance with the age of the planets and the degree to which they have been influenced by the successive sojourns of the divine Sons.

^49:4.8 ¶ Mind is the bestowal of the Infinite Spirit and functions quite the same in diverse environments. The mind of mortals is akin, regardless of certain structural and chemical differences which characterize the physical natures of the will creatures of the local systems. Regardless of personal or physical planetary differences, the mental life of all these various orders of mortals is very similar, and their immediate careers after death are very much alike.

^49:4.9 But mortal mind without immortal spirit cannot survive. The mind of man is mortal; only the bestowed spirit is immortal. Survival is dependent on spiritualization by the ministry of the Adjuster — on the birth and evolution of the immortal soul; at least, there must not have developed an antagonism towards the Adjuster’s mission of effecting the spiritual transformation of the material mind.

^49:5.1 It will be somewhat difficult to make an adequate portrayal of the planetary series of mortals because you know so little about them, and because there are so many variations. Mortal creatures may, however, be studied from numerous viewpoints, among which are the following:

^49:5.2 1. Adjustment to planetary environment.

^49:5.3 2. Brain-type series.

^49:5.4 3. Spirit-reception series.

^49:5.5 4. Planetary-mortal epochs.

^49:5.6 5. Creature-kinship serials.

^49:5.7 6. Adjuster-fusion series.

^49:5.8 7. Techniques of terrestrial escape.

^49:5.9 ¶ The inhabited spheres of the seven superuniverses are peopled with mortals who simultaneously classify in some one or more categories of each of these seven generalized classes of evolutionary creature life. But even these general classifications make no provision for such beings as midsoniters nor for certain other forms of intelligent life. The inhabited worlds, as they have been presented in these narratives, are peopled with evolutionary mortal creatures, but there are other life forms.

^49:5.10 1. Adjustment to planetary environment. There are three general groups of inhabited worlds from the standpoint of the adjustment of creature life to the planetary environment: the normal adjustment group, the radical adjustment group, and the experimental group.

^49:5.11 Normal adjustments to planetary conditions follow the general physical patterns previously considered. The worlds of the nonbreathers typify the radical or extreme adjustment, but other types are also included in this group. Experimental worlds are usually ideally adapted to the typical life forms, and on these decimal planets the Life Carriers attempt to produce beneficial variations in the standard life designs. Since your world is an experimental planet, it differs markedly from its sister spheres in Satania; many forms of life have appeared on Urantia that are not found elsewhere; likewise are many common species absent from your planet.

^49:5.12 In the universe of Nebadon, all the life-modification worlds are serially linked together and constitute a special domain of universe affairs which is given attention by designated administrators; and all of these experimental worlds are periodically inspected by a corps of universe directors whose chief is the veteran finaliter known in Satania as Tabamantia.

^49:5.13 2. Brain-type series. The one physical uniformity of mortals is the brain and nervous system; nevertheless, there are three basic organizations of the brain mechanism: the one-, the two-, and the three-brained types. Urantians are of the two-brained type, somewhat more imaginative, adventurous, and philosophical than the one-brained mortals but somewhat less spiritual, ethical, and worshipful than the three-brained orders. These brain differences characterize even the prehuman animal existences.

^49:5.14 From the two-hemisphere type of the Urantian cerebral cortex you can, by analogy, grasp something of the one-brained type. The third brain of the three-brained orders is best conceived as an evolvement of your lower or rudimentary form of brain, which is developed to the point where it functions chiefly in control of physical activities, leaving the two superior brains free for higher engagements: one for intellectual functions and the other for the spiritual-counterparting activities of the Thought Adjuster.