Science in Christian Perspective
Look Down the
RICHARD S. BARNETT
Continental Oil Company
Lafayette, Louisiana 70501
From: JASA 28 (March 1976): 21-23.
Change touches all created things. Living species can change from place to place and with the passage of generations as the result of natural processes which alter the genetic composition of populations.
This view of life need force no one to deny God a role in the origin of life. Although biological change has a vital place in the plan of God for all Creation, it is definitely, a limited place. Observed patterns of change in populations do not suffice to initiate the rise of new life forms with a capacity for development. The eye of reason can see the hand of God in direct control at this point, just as clearly as the eye of faith.
"Education," wrote Aldo Leopold, "is learning to see one thing by going blind to another."1 That kind of education helps to account for the rancor between Christians and scientists in their endless wranglings over the origins of life. Blind arguments from both sides belie their claims to enlightenment. Both sides discredit themselves in the process of arguing. It appears to one with vital interests on both sides that one side might at least begin to resolve the issues by using the insights of the other. I proceed on the premise that neither Christians nor scientists need let themselves be forced into either/or extremes. My own experience is that a Christian who is a scientist has an incomparable insight into the dimensions of space, time, and truth. I propose to illustrate this by sharing a geologist's perspective into the prickly subject of organic evolution.
Evolution means simply a process of growth and development. Within the provocative context that we are interested in, organic evolution is the hypothesis that all existing life originated from inanimate matter in the remote past and developed into successively more complex forms by natural processes including mutation, selection, and adaptation.
The evolutionary hypothesis owes its widespread acceptance to its ability to satisfy our questions about why life has not always been just as we see it today. The answers appeal to nothing more mysterious than the familiar biological mechanisms that we apply in plant and animal breeding. Objections to the hypothesis center on the fact that one may use it to infer that life arose without divine intervention or control. Pioneers of the evolutionary hypothesis recognized the materialistic side of this conclusion, and earnestly disavowed it. It remains with us, nonetheless, because enemies of our faith have made it their own.The Fact of Change
eliminate the false conclusion and its corollaries by taking another look at the
fact of change, the basic premise in evolutionary thought. This much bears
examination, because not even the everlasting hills are changeless or forever
and always fixed and immutable. The whole of the known universe is in a state of
motion and dynamic change which is anything else but mere decay or running down.
Instead of quibbling about that, "Let the great world spin for ever down
Looking more closely at the grooves, we discover that change is a genuine characteristic of life. Change is itself the expression of two primary attributes of all living things: diversity and individuality. Reproduction without diversity and individuality would be vegetative replication in mechanical conformity to a single mold. Diversity preserves individuality. Therein reside the biological prerequisites for human personality and freedom, two essentials of the nature of God, his image and his purpose.
From this point of view, the bare fact of change in living things does not constitute adequate grounds for denying God a role in the origin of life. The error of any such denial shows forth plainly in a review of the nature and extent of biological change in the present and in the past.
What we can observe in living species is change from one generation to another. The array of genetic characteristics possessed by one generation is never uniformly carried over into the next. This is, first, because no one individual can possess each and every possible character of the species. Second, only a part of each generation shares in the procreation of the next, and unequally at that. This is the result of numerous different processes ranging from involuntary to deliberate, random to selective, natural to cultural, and geographic to sociological. These processes combine to determine which part of one generation engenders the next. They act to subdivide a species into small, loosely linked populations within which interbreeding is more active than between groups. The breeding populations are continually subject to fractionation and differential recombination, which preserve and intensify the genetic combinations determining some characteristics while repressing or removing others. A given species would have to maintain random free breeding within a large, homogeneous population in order to keep from becoming inconstant in some features from one place to another. In time, a species can actually undergo 6ollective modification in some gene combinations. Variation between individuals at any time and place is always so great that statistical comparison of groups of individuals is needed to make objectively perceptible any temporal trend of change in any characteristic.
Authenticated changes of this limited and subtle extent lead to the subdivision of a species, with the gradual divergence of new taxonomic units at the lowest levels-race, variety, subspecies, or species. The new forms can be differentiated from the old by subjective or statistical details of form and size or by differences in adaptation to habitat. The two often prove to be still capable of interbreeding in zoo or laboratory conditions. Change of this limited scope is not the same thing as the emergence of new life forms. Darwin's finches, the textbook prototypes of speciation by adaptive radiation in geographic isolation, are no more than finches. We do not witness the emergence of new taxonomic units at the generic level or above. The processes leading to speciation end up in specialization at the expense of the potential for development in new directions. None of Darwin's finches have taken up the habits of kingfishers or cuckoos, shrikes or hummingbirds. Monkeys could never develop into anything but monkeys.
If we have not actually observed the natural emergence of significantly different new life forms, we are assured that is due to the brevity of our observation. Time and mutation account for the evolutionary advance. Genetic mutation has been pictured as the fuel of evolution, that is, as the source of new inheritable characteristics or modifications in existing characteristics.3 The natural action of adaptive and selective processes in time gives rise to new genera. Yet observed mutations simply do not happen systematically according to the schemes that would usefully advance the development of new characteristics and so transmute a species. Instead, natural mutations, which occur spontaneously with measurable frequencies, are random in the characteristics they affect and their effects are quite the opposite of advances. They constitute genetic aberrations that result in unfortunate if not predominantly pathological manifestations such as dwarfism and albinism. Extreme aberrations are more or less non-inheritable and, in any case, natural reproductive patterns further act to eliminate even non-lethal mutations in both dominant and recessive genes. Laboratory mutations, induced by chemical, thermal, and radiogenic means, are consistently lethal.
But time is again invoked, together with the probability that some mutations are eventually beneficial and capable of being shared, preserved, and developed. You may accept that if you regard time as the domain of random probability. The geological record of time and life has its own witness in this connection.The Geological Record
The record of the rocks, selective and fragmentary though it is, contains an orderly succession of fossil species. That they are actual organic remains and not diabolical counterfeits is known from their structural and biochemical affinity or identity with life today, as well as from evidences of their life associations and habits. The fossil remains are related to living species in some way, and successively younger strata contain an increasing proportion of extant genera and species. Not even seemingly-bizarre extinct forms are alien or unrelated to life today.
Within the fourth dimension which parallels the vertical dimension of the geological record, it is possible to confirm that a species is not forever fixed and frozen in all its anatomical characteristics. Transformation in response to time and environment is traceable. The temporal descent of one chronological species from another was first traced meticulously in Silurian corals of the genus Zaphrentis by the Englishman Carruthers,4 and has been repeated in species representing other animal and plant orders.
Changes in some forms were accompanied by the disappearance of other forms of life. The old ones left quietly, usually slowly, although abruptly on occasion. Repeated extinctions did not come about as the suppression of spurious or defective creations. The extinctions were a part of the long continuing processes which shaped the earth as it is today, a living and fertile blue planet with no known habitable neighbor at hand in the lifeless reaches of cosmic space. The former existence of now-vanished species changed the earth in numerous subtle and unobtrusive ways that prepared it for their successors and for eventual human habitation.Biological Laws
Four propositions have been advanced as biological laws that govern the evolution of new generic stocks. They are Dacque's principle, Williston's law, and Cope's laws.5 Dacque's principle asserts the parallelism of adaptive radiation in related stocks, Williston's law is based on his observation that the specialized development of some organs or faculties is accompanied by a reduction in the number and the importance of others. Cope's laws are his conclusions derived from observations that the most durable species in the stratigraphic record are those least specialized in structure and adaptation to habitat, and that the development of generic stocks is accompanied by increase in size. The second law is also known as Deperet's principle.6 Still more basic than these conjectural principles are certain characteristics of the way each new stock appears. First, their initial appearance is lost to the geological record, as if in accordance with Teilhard de Chardin's opinion that the "peduncles" of phyla are naturally suppressed.7 Secondly, when fossil evidence is first detectable, new generic stocks have already begun to progress and diversify in distinctive directions because they are already endowed with an enormous genetic potential for development and radiation. Thirdly, the new stocks are already equipped with sets of novel characteristics or novel forms of existing characteristics. The new equipment is functional and has positive survival value from the start: that is, organisms do not have to either inherit acquired characteristics or wait until new organs or faculties are completely developed before they are usable.The Mark of Purpose
These three characteristics of generic development bear the hallmark of purpose, not chance. They affirm the divine creation and introduction of high taxonomic units at discrete and chosen times in accordance with a divine plan. The biological advances recorded in the fossil succession were brought about by the active direction of God. Change lies within his control as a tool in his continuing creative activities. Biological and other natural sources cannot explain the appearance of the characteristics that distinguish new life forms.
The creative activity of God is the only plausible source of entire suites of viable genetic potentialities for biological advance.
mechanisms for speciation are one-way processes that lead to irreversible specialization rather than toward generalization or innovation. Neither adaptation nor selection initiate the appearance of new characteristics. Mutation generates useless aberrations in a few characteristics. That leaves the creative activity of God as the only plausible source of entire suites of viable genetic potentialities for biological advance.
Theories of organic evolution fail to explain man or much else. Nothing plus inanimate chaos plus impersonal chance or necessity plus time simply do not add up to man or even to life in general. The only correct element in the equation is time. Add God plus purpose plus order, and the sum is man.
By his wisdom, the Lord founded the earth (Proverbs 3: 19). If the earth and all created things are changing and changeable, the fact of a changing creation does not deny the fact of an unchanging Creator. He laid down the ringing grooves of change also. The very changeability of the universe and all living things, and the geologic record of changes stand as further examples of how all creation joins with the starry firmament in proclaiming the glory of God, our Lord, the one Creator of all things visible and invisible.