The living world provides us with an apparently inexhaustible supply of marvels and mysteries. Books, magazines, films and television have found that the appetite of the general public for these things is undiminished. Why are lions and tigers so similar and yet so distinctively different? And surely they are related in some way to the domestic cat? What about all the different finches in the world? They have so much in common, yet they retain their separate identities. Questions of origins and ancestry arise naturally, and cannot be sidestepped. This article is concerned primarily with the explanation of these relationships which is presented by our educational system and by the media.
Models of evolutionary change, which attempt to explain the common ancestry of all living things on Earth, are dominated by the theory of evolution by natural selection. This approach is linked permanently to the name of Charles Darwin, whose treatise On the Origin of Species in 1859 captured the minds of Victorian scientists over a period of some twenty years.
This assessment of Darwinism will not involve a detailed discussion of evidences. Rather, we will look at the type of evidence, the inferences and the assumptions that are being made. Consequently, the argument will be accessible to non-scientist and scientist alike.
Darwinism draws attention to a number of observations about living things:
Observation 1
Offspring outnumber parents. Sometimes this is
marginally the case - as when a pair of
birds raise just one chick per year - but after
three years, the
observation becomes true. Many more animals produce
large numbers of offspring -
consider, for example, the number of caterpillars
coming from a cabbage
white butterfly, or reflect on the population of
tadpoles appearing in the local pond.
Observation 2
Species numbers remain approximately constant.
There are good years and bad years
for all the animals we know - but we are not being
overrun by
robins or cabbage white butterflies or frogs. These
observations lead to an:
Inference
Observations 1 and 2 suggest that there is a struggle
for survival. Some offspring die
without descendants of their own. There are losers
in the game of
life.
Observation 3
Individuals differ in small ways, and many of these
differences are inherited from
parents. The observation applies to people, as
we can confirm by
looking at parents and children known to us. In
fact, it applies to all organisms -
wherever we can look closely enough.
Conclusion
Those individuals whose variations adapt them to
their environment will be the most
likely to survive and reproduce. This conclusion
is commonly described as
the principle of natural selection.
Everything above is non-controversial and not particularly complex to understand. Only after this point in the argument comes a divergence of view: some think that the above analysis is a theory of origins, whereas others consider it a theory of ecology. Darwinists take the former view, asserting that we have here a sufficient explanation of the origin of all biological species. Non-Darwinists, including creationists, are not convinced. They argue that crucial evidences relevant to any theory of origins are totally lacking.
The points made so far can all be illustrated by reference to one of the classic examples of natural selection: the Peppered Moth. Like all moths, this particular species lays numerous eggs which develop into large numbers of caterpillars (observation 1). Over the years, the Peppered Moth has maintained its population level reasonably well (observation 2) which implies that predation and death are important factors affecting overall numbers. The Moth has a variable appearance and exists in three forms: dark-coloured, light and speckled. These differences are inherited from parents (observation 3). The conclusion, that `those individuals whose variations adapt them to their environment will be the most likely to survive and reproduce' , has been tested by observations of predation. In environments where dark surfaces predominated, the light-coloured moths were found more easily by birds and eaten. In such cases, the population came to be dominated by the dark form. This was natural selection in action. Conversely, in enviroments where there was a dominance of light surfaces, the light form was more numerous. Changes in the environment over time, due to the effects of industrial pollution, resulted in changes in the relative numbers of light and dark forms.
The conclusion is interpreted in different ways: Darwinists hail the Peppered
Moth as an important example of evolution by natural selection; non-Darwinists
accept that natural selection of an inherited characteristic is occurring,
but resist the thought that this has any bearing on the origin or ancestry
of the Peppered Moth. The non-Darwinian argues that adaptation potential
is a necessary component of any theory of ecology, where populations respond
in some way to their environment. Why is this part of a theory of ecology?
It is related to the fact that the environment continually changes. If organisms
are to be robust, with some powers of endurance through the generations,
there must be some `oscillation potential' . This is exactly what we see
in the Peppered Moth.
Theory of origins
What more is needed to make a theory of ecology into a theory of origins?
Three assumptions are required, and it is vitally important for science
that the assumptions
be recognised and subjected to investigation.
Assumption 1
Appropriate variations constantly arise, introducing
fresh information to the genetic
composition of organisms. Observable variations
which do not
affect genetic information are not appropriate
for evolutionary theory.
Assumption 2
There is no limit to the succession of variations
that can occur, so that major
evolutionary transformations are possible.
Assumption 3
Natural selection is the mechanism for preserving
novel adaptive variations. Predation
removes information represented by prey; extinction
erases genetic information
permanently; and reporduction transmits information
to the next generation. The
assumption is that selective forces act to preserve
new information in survivors.
Assumptions 1 and 2 relate to the character of the variations that occur, allowing the possibility for new information to be introduced to an organism, and assumption 3 is concerned with the preservation of that new information.
These assumptions are necessary to convert the non-Darwinian theory of ecology into a Darwinian theory of origins. Consequently, only evidence for these assumptions can count as evidence for evolution. This requirement for proof is one that must be addressed by Darwinists if they are to persist in describing their theory as a scientific approach to the study of origins.
Darwinism went through a crisis in the early part of the Twentieth Century,
because the science of genetics was developing, and it appeared to explain
away most, if not all, of Darwin's evidences of variation. Observed variations
due to artificial selection, such as in dogs or pigeons, are irrelevant
to evolutionary change, as no new information is introduced and the range
of variation is limited. The three assumptions appeared to be groundless.
Some biologists abandoned Darwinism and embarked on a quest for alternative
explanations.
Mutations
In the 1930s, leading geneticists found a way of preserving the theory of evolution by natural selection. They discovered that a variety of errors occurred in the copying of genetic information during reproduction. These errors are known as mutations. The 3 assumptions were revived: the blending of Darwinism with genetics became known as neo-Darwinism. It is our task to enquire whether these assumptions can now be regarded as proved.
Enormous effort has been devoted to researching this area, partly to elucidate the mechanisms of evolution, and partly to explore the potential for speeding up evolutionary change to breed plants and animals with characteristics suitable for commercial exploitation. As a result, we know a great deal about different types of mutation, and the changes they bring to organisms.
Very little attention has been given to the three Darwinistic assumptions! In most cases, they have been assumed as part of the framework of knowledge of the researcher. Consequently, very little testing of the theory has taken place. Although this may seem surprising to those outside science, it is actually a very common phenomenon. Much scientific research takes place in the context of particular presuppositions, and it is rare for the foundations to be tested in formal ways.
Nevertheless, it is possible to make some assessment of the assumptions
of Darwinism and neo-Darwinism. The key word in Assumption 1 is `appropriate'
. The implication is that some mutations will be beneficial to the organism.
Unfortunately for the theory, this is not confirmed. The list of harmful
mutations is long; the list of beneficial mutations is short - and questionable!
In human beings, known mutations are all harmful. One case - that of sickle
cell anaemia - provides some protection against malaria. However, apart
from that one asset, the condition is not recommended. Sickle cell anaemia
represents an assault on the way blood cells work. There is one beneficial
effect, but this is counteracted by harm done to the human physiology system.
A vivid demonstration of this claim has come from observations of humans
(with sickle cell anaemia) operating under extreme conditions, where some
have been known to collapse and die. All examples of supposedly `beneficial
mutations' fit the general pattern: the trend is downward. Organisms experience
the process of `death by instalment' . Our conclusion is this: the first
Darwinistic assumption is retained, not by scientific evidence, but by appealing
to chance over extended periods of time - `given long enough, favourable
mutations must
occur' .
The second assumption: that `there is no limit to the succession of variations that can occur', is similarly safeguarded only by an appeal to theory and long periods of time. No scientific investigation has ever confirmed the assumption, and all the substantial evidence suggests the contrary. One reason is that all organs of animals and plants are extraordinarily complex, and are composed of many interrelated elements. Whether we think of the eye, the ear, the nose, or any part of the body - a few mutations can be allowed, but too many leads to the complete loss of function. The mysterious complexity of living things is an indicator that unlimited variation is not possible.
We come to assumption 3: `natural selection is the mechanism for preserving novel adaptive variations' . There is no doubt that natural selection can be understood as a force in ecology: moulding organisms according to their innate potential for variation. It can lead to the emergence of new species. The problem for neo-Darwinists is that not a single case can be identified where new genetic information has been demonstrably preserved by natural selection. All the examples are of oscillation, with no loss or gain of information.
You may have been impressed by seeing computer models of evolutionary variations - but they are all committed to these assumptions. It is relatively easy to create a theoretical world which evolves according to the rules and assumptions of neo-Darwinism. The key question is: does this theoretical world adequately represent the real world? The only way to find out is to subject the theory to scientific investigation - and the evidence shows grave mismatches between this theory and reality.
So where does this discussion leave us? The dominant explanation of origins rests, not on a scientific foundation, but on philosophical and metaphysical presuppositions. What about the scientific evidences? Those that relate to the observed variations in living things are consistent with the teaching of the Bible: that God created all the different kinds of living thing, and that they reproduce after their own kind. A good foundation for the science of biology is to be found here. The concept of a created kind maintains the existence of discontinuities between the life-forms that emerged from the hand of God, and at the same time allows for limited variation. The concept of a created kind leads to the recognition of intelligent design in the way organisms are made. A creationist biology will develop tools - which are sadly lacking from the repertoire of contemporary biologists - that assist in these studies of discontinuity and design.
A number of Christians differ strongly from the analysis presented here. They claim that there is a scientific theory of evolution (neoDarwinism) which they find acceptable, but that evolutionism, which springs from atheistic philosophy, is unacceptable. This article explains why this view is fallacious: there is no scientific theory of evolution! The time is long overdue for the atheistic roots of all evolutionary theories to be addressed by the Christian community.
David J. Tyler and Arthur J. Jones (1992)
