PART I

SCIENTIFIC BASES
OF THE THEORY OF EVOLUTION


CHAPTER 1

[27] Historical Development of
the Theory of Evolution

1.1 Antiquity of Evolutionary Thought
 

The evolution controversy began many centuries ago. It has had a stormy history no matter what the nomenclature or who was involved. The development of the theory has produced a fascinating struggle that needs to be understood by Christians with an interest in science so that they can better comprehend current world views.

The development of the theory reaches far back into history. Even in ancient Greece two opposing views on cosmological change (evolution) were popular. Parmenides (515 B.C.-?) advocated a concept of eternal absolute being. This view adopted the concept of the changeless quality of true being. Apparent changes in the world of phenomena were explained away on the basis of the rearrangement, separation, and union of small unalterable particles. Heraclitus (540-475 B.C.), on the other hand, conceived of the cosmos as being in a continual, universal process of flux, involving cycles of generation and decay. Individual things were perceived as maintaining themselves permanently against the universal process of destruction and renovation (1).

Aristotle (382-322 B.C.), who believed in a purposive force directing all natural phenomena, first approached the nature of change in the living world by classifying plants and animals. He stated that all the different "forms" of living organisms were abruptly created from a primordial mass of "living" matter, a theory later recognized as spontaneous generation (2). The influential philosophy of Aristotle and the later adoption of his thoughts by the medieval church and states stifled further attempts to [28] explain change in the living world for more than a millennium. However, from ancient times, the existence of diverse races of men and breeds of domestic animals gave evidence of continual minor changes within species. Variations in the living world caused the curious to search for an intellectual explanation, and the belief that organisms have not changed since their creation was challenged by the opposing view that parental life experiences can lead to the acquisition of new traits in the offspring.

After the Copernican revolution and the Enlightenment, the intellectual atmosphere was more conducive to the pursuit of new ideas regarding change within living organisms. Maupertuis (1698-1759) may have been the first to propose a general theory of evolution (2). He based his theory on a study of the history of four generations of a human family in which polydactyly (a congenital defect involving the appearance of a web of muscle and skin between fingers and the production of additional fingers) was inherited. This was later recognized as a dominant gene. He noted that this trait could be transmitted by either parent who was affected and suggested that certain particles from the parents, which might be changed by climatic and nutritional influences or by irregularities of their distribution, were responsible for the inherited change in the offspring. Thus, he recognized the phenomenon of descent with possible modification. However, Maupertuis made little impression on the biologists of his time.

George de Buffon (1707-88) maintained that species were separately created, but he supported a limited evolution within species due to climatic and nutritional effects on inheritance. He also speculated about possible evolution above the species level by adopting less rigid criteria for defining a species (see I. 1.2).

Darwin's grandfather Erasmus Darwin (1731-1802) first alluded to the term evolution to designate the process that involved "the power of acquiring new parts, attended with new propensities, directed by irritations, sensations, volitions and associations and thus possessing the faculty of continuing to improve by its own inherent activity and of delivering these improvements by generation down to its posterity world without end" (3). However, his thesis was highly speculative and had little effect on biological thought.

Chevalier de Lamarck (1744-1829) developed a theory using an echelon of progress from inert matter to a simple form of life that finally culminated in the existence of man. He recognized branching in his echelon of progress that he attributed to the inheritance of acquired characteristics as a result of the organism’s adaptation to the changing environment. His theory also allowed for occasional organismal degeneration [29] instead of progress. Lamarck's ideas produced a dynamic impact on his contemporaries and were little refuted until early in the twentieth century. However, Geoffrey Saint-Hilaire (1772-1844) suggested that the occasional deviant form of an organism may be the raw material for the evolution of new types, provided the abnormal form survived. Saint-Hilaire's theory helped lay the groundwork for the understanding that mutations provide a source of genetic diversity needed for evolution to occur through natural selection.

The concept of natural selection was separately conceived by two social scientists, namely, Thomas Malthus (1776-1834) and Herbert Spencer (1820-1903). Malthus in his Essay on Population argued that every population outgrows its food supply, and eventually starvation, disease, and war set in to prune the population because an arithmetically increasing food supply cannot catch up with a geometrically increasing population. Later, Herbert Spencer showed how the Malthusian theory can be used to explain the force behind the progress of human society. He recognized that there was a societal tendency to place a premium upon skill, intelligence, self-control, and the power to adapt through technological innovation; thus, there was a selection of the best of each generation for survival. Spencer coined the term survival of the fittest. This term and the term struggle for existence, previously set forth by Malthus, were later used by Charles Darwin (1809-82) as slogans for his concept of natural selection.

Darwin's contribution to the development of evolutionary thought was to provide a mechanism, natural selection, to account for the observed changes in domesticated livestocks and natural populations. While on a sailing expedition to South America in 1831, he was impressed by the seemingly isolated occurrence of large groups of mammals not found in the Old World and particularly the multiple species of plants and animals peculiar only to the Galapagos Islands off the coast of Ecuador. This led him to speculate that immigration of species from old to new isolated habitats resulted in the origin of new varieties and species.

In the same period Alfred R. Wallace (1823-1913) proposed the identical theory as a result of his studies on the distribution of animals in the Malay region. Darwin and Wallace successfully attracted the attention of the scientific community by presenting their theory in London to the Linnaean Society in 1858. Upon the publication of The Origin of Species by Means of Natural Selection in 1859, the public became exposed to Darwin's idea of evolution. Since Darwin's theory revolves around the concept of species, it is essential to establish a working definition of the term. [30]



References 1.1

1. Nordenskiold, E. The history of biology. New York: Tudor; 1928. Eyre, L. B., translator.
2. Glass, B. “Maupertuis, pioneer of genetics and evolution.” Glass, B.; Temkin, O.; Strauss, Jr., W. L. 1745-1859 eds. Forerunners of Darwin. Baltimore: John Hopkins; 1959: 51-83.
3. Darwin, E. Zoonamia. Vol. 1. Boston: Thomas and Andrews; 1803 (Preface).