Charles Darwin

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More than a century after his death, and four generations

after the publication of his chief work, 'The Origin of Species',

Charles Darwin may still be considered the most controversial

scientist in the world. His name is synonymous with the debate

that continues to swirl around the theory of evolution, a theory

that deeply shook the Western view of humanity and its place in

the world.

We tend to speak simply of the theory of evolution, leaving

off the explanatory phrase, 'through natural selection.' At most,

perhaps, the general public has heard of 'survival of the

fittest' a poor phrase as far as I'm concerned, since fitness in

everyday usage is associated with physical conditioning and

athletic ability. 'Survival of the most suited to its

environment' would be a more accurate, and convincing expression

for this pedicular concept. But to most of us, 'evolution' simply

means that human beings are descended from apes, a slight

misunderstanding, since both humans and modern apes are

descendants of a mutual ancestor that is now extinct.

It's not

evolution but the theory of natural selection and the evidence he

collected to prove to fellow scientists, peers, students, and

most importantly the masses of public and the church that were at

the heart of Darwin's contribution to biological science.

Charles Darwin did not invent the concept of evolution. A

number of prominent scientists and other thinkers during the

eighteenth century and the first half of the nineteenth century

(among them Charles Darwin's grandfather, Erasmus Darwin) had

offered detailed theories of evolution (Clark, 1984, pg.24-25).

Therefor the idea of evolution went very far back in Western

history.

At that time this concept was referred to as The Great Chain

Of Life and was conceived in the middle ages, based on a mixture

of classical and Biblical ideas. The ranking order ranged from

the 'lowest' forms of life to 'higher' living beings (lion),

through the various classes of human beings from peasants to

nobles to Popes, and upwards through the hierarchy of angles to

God.

This concept, in and of itself, has nothing to do with

evolution, in fact it seems to be anti-evolutionary, since every

member is fixed in its own place. This chain was created in a

time when the world was considered to be more static rather than

a diverse collection of dynamic ideas.

But the Newtonian revolution of the seventeenth century

replaced the old static world with a new world view in which

everything was naturally in motion. In the course of the

eighteenth century the notion of progress, of gradual but

relentless pursuit of betterment, began to take hold in western

thought. It was only natural that the ideas of change and of

progress should eventually be applied to the Great Chain of

Being. The natural implication of a 'dynamic' chain of being was

a sort of tree of life, gradually sprouting upward from basic

primordial ooze, branching outward into all the varied species on

our fine planet, ending with, of course, eighteenth century Man.

This could be called evolutionary, but it does not offer a

theory of evolution, an order in which evolution took place. It

was no longer acceptable to say 'God did it'. Therefor, if

evolution was to ever become a science, a rational explanation

had to be offered.

Such an explanation was proposed by Jean Babtiste Lamarck

toward the end of the eighteenth century, and Lamarck became best

known for his pre-Darwin theory of evolution. According to

Lamarck, the acquired characteristics of the parents could be

handed down to their offspring. Suppose, to take the most over

used example, that the first generations of giraffe had a neck of

ordinary length. Because the lower branches of the trees they fed

off were easily striped, these early giraffes stretched out their

necks to reach higher branches. In doing so, they caused their

offspring to be born with slightly longer necks, until the

ultimate result was the giraffe of today.

This theory had virtues far beyond the necks of giraffes.

Taking this concept to its extreme one would now be under the

impression that all that the past European forefathers have

passed on all their acquired traits to the younger generations

following them. The reasoning powers of the great philosophers,

the valour of Crusading knights should have been endowed in all

rather than a meagre few. According to this theory of evolution

descendants could one day attain the heights Europeans had

already scaled.

The Lamarckian evolution had only one crucial defect, it was

entirely untrue. One could cut off a rat's tail, but its

offspring would have normal tails. The rules of genetics were not

known in Lamarck's day, and were not known until long after

Darwin's, when the pioneering work of Mendel was rediscovered at

the turn of the twentieth century. But animal breeders had long

since discovered certain principles of breeding for desired

characteristics, and acquired characteristics played no part in

this process. Only through proper training could one find out if

a hunting dog had favourable qualities. But the training did not

create those characteristics in the dog's offspring.

Lamarckianism was now discredited, and the question of

evolution remained a mystery. Many scientists rejected evolution

and the Great Chain of Life feeling that its concepts had no

place in biological science. The key was produced by the theorist

of the 'dismal science' of economics, Thomas Malthus. Malthus

said that human (and animal) populations increased at a geometric

rate, whereas food supply increased only at an arithmetic rate.

Therefore population was continually outstripping food supply,

and was kept in check only by starvation, or by indirect acts

such as war and diseases.

Malthusianism raised a very good question which is not easily

noticed. Which individuals survived in hard times, and which

died? Luck was probably the largest factor, but not the only one,

other factors applied, such as the strong, the courageous, or the

adaptable had a somewhat better chance of surviving than those

who lacked those characteristics. To the degree that strength,

drive, or adaptability were acquired characteristics, they would

have no effect on future generations since Lamarckianism had been

proven wrong. But to the degree that some individuals inherited

these characteristics, they were more likely to survive, to hand

down these same characteristics to their descendants. As the

lower branches of the ancient African trees were plucked bare,

the longer-necked ancestral giraffes were more likely to survive

than their shorter-necked cousins, and they handed down the

tendency toward long necks to their descendants. The modern,

long-necked giraffe thus evolved through countless generations of

natural selection.

A few people may have stumbled upon this idea before Darwin

did, but Darwin was the first to develop it. The development was

indeed more crucial to the ultimate acceptance than was the

insight alone. By itself, evolution by natural selection is an

amazing theory, and although this might explain a great deal, it

does not prove that it is true. Lamarckianism was amazing in its

time but it did not stand up close to scrutiny.

Before offering his insight to the world, Charles Darwin

determined that he would subject it to close scrutiny. He spent

the next two decades of his life collecting masses of evidence,

from the distribution of natural species to the experience of

pigeon breeders, to develop and support his argument. As far as

he was concerned, Darwin was nowhere near ready to present his

theory when, in 1858, Alfred Lord Wallace, sent a paper to him.

Wallace's paper stated the very theory that Darwin had been

labouring on for two decades. Soon a joint paper was written and

published , and the theory of evolution through natural selection

was at least presented to the scientific world (Darwin and

Wallace, 1858). Two years later Darwin published his full theory

in The Origin of Species.

If Thomas Edison said that invention was one percent

inspiration and ninety-nine percent perspiration, Darwin showed

that the same was true of discovery. Evolution through natural

selection was a brilliant idea, and one that might be debated

endlessly.

The process through which one species evolved into a

distinctly different species was far too time consuming to be

directly demonstrated. All the naturalists had available, apart

from bones, was an understanding of the state of life as it is on

earth today. Essentially, The Origin of Species approached the

problem of evolution through two lines of argument and

interpretation, both rooted in the concept of inherited

variation. Darwin showed that the distinction between species was

not hard and fast. There are varieties of a given intricately

adapted to different conditions, that routinely interbred along

the boundary between their home territories, but the mixed

varieties tend to remain confined to the boundary area, since

they are less adapted than either of the base varieties to their

own home territories. Specification in nature did not require

dramatic jumps, but could emerge out of gradually widening

variation.

Darwin examined variation under domestication to demonstrate

that the deliberate selection of breeders could produce varieties

as markedly different from the root stock as the varieties found

in nature. Deliberate selection through breeding was obviously a

much faster and 'efficient' process than natural selection

through differential rates of survival in the face of

environmental pressures, but the end result would be essentially

the same, the variety of a given species that was most adapted to

a given environment would gradually replace the root stock in

that environment.

The theory of evolution through natural selection would most

certainly have appeared, even without Darwin, it would have

appeared at the same time, since it was Wallace's independent

development of the theory that prompted his and Darwin's joint

paper. The idea of natural selection was circulating in the mid-

nineteenth century, just as the idea of evolution had been

circulating in the eighteenth.

But had the century of evolution through natural selection

appeared only in outline form, it might have been many more years

in winning general acceptance. The collected evidence of The

Origin of Species was sufficient to persuade most biologists that

this was the key that they had been looking for. Quite a few

scientists held out, notably Louis Agassiz, but the younger

generation of students coming into the field seem almost without

exception to agree to the adopted theory. Within a few decades,

evolution through natural selection was a fundamental paradigm of

biological thought.

The development of biology through the century since that time

has not essentially altered the situation. Alot of changes have

been introduced, or at least debated. Once genetics was more

fully understood, it was realized that major steps in

specification might just owe more to favourable mutations than to

the regular process of variation. But the introduction of

mutation did not change the principle of natural selection.

Natural selection, as Darwin saw it, simply can not be

ignored. For just as a largely barren earth is re-colonized by

the survivors descendants, which must adapt through either

variation or mutation to fill the ecological niches left empty by

the prior extinctions. Just as an area devastated by a forest

fire are filled by an evolution of new forms, not by the existing

ones from unburned areas. We may not be able to see the entire

history of evolution but from our viewpoint we have hundreds of

examples of natural selection taking place all around us each and

every second of each and every day. Fortunately, Charles Darwin

(and maybe I should credit Alfred Lord Wallace) had the insight

and boldness to conceive and develop a theory so controversial to

his time and culture.

Chad Galloway

Clark, R.W. (1984). The Survial of Charles Darwin. New York:

Random House

Sproule, Anna (1990). Charles Darwin. Concord:Irwin

Warburton, Lois (1992). Human Origins-Tracing Humanity's

Evolution. San Diego:Lucent Books

Howell, F.C. (1980). Early Man. Virginia:Time-Life Books

Nouvelle, C (1885). The First People. Paris:Silver Burdett Co.