Evolution and stuff...

7/30/2019 Evolution and stuff...

1/12

Abstract

One of the key differences between any other scientific theory and evolution is the amount of

controversy the latter has invited. The major share of the debate concerning evolution (especially in the

popular literature), while superficially about its scientific legitimacy and truth claim, actually stems from

the repercussions it is construed to lead to. It is generally asserted that the truth claims of worldviewsstand or fall with the truth of evolution. The present article will deliberate upon whether this assertion is

true with the Islaamic worldview.

In this regard, two things need to clear from the onset. First, this article asserts that the Quranic

narrative of the creation of man is literal. The literal reading of the relevant verses tell us that Allah

created the first man with His hands (38:75) from an extract of clay, wet earth, sounding clay or sticky

clay, all of which presumably refer to the different stage of mans creation (3:59, 23:12, 37:12, 15:26,

55:14), and then spirit was breathed into him (38:71-72). Second, while we acknowledge the scientific

legitimacy of the intelligent design movement[1], the present article would assume that the evidences

suggested for evolution are valid.

Therefore, the subject matter of this article can be articulated thus: does the evidences for evolution

discount any Islaamic theological precept, especially the possibility of God having supernaturally created

the first man?

To achieve this end, the article will first define what evolution is and draw a basic outline of the

evolutionary mechanism. Then we will move on to chalk out the implications of evolution that may

stand in conflict with any theological precept of Islaam, and consider them in turn. The article will close

with a discussion of whether the creation of Adam story according to the Quran contradicts any other

scientific idea apart from the theory of evolution.

What is evolution?

If you wish to converse with me, define your terms.Nowhere are Voltaires words more relevant than

modern discussions about evolution. Evolution is a stretchy word, in that it can be taken to mean

different things. In popular culture, evolution is only as relevant as its repercussions, and as such it is

almost ubiquitously used (especially in Muslim circles) to refer to evolution of man from apes. However,

the term entails so much more. To address the subject matter of this article, it is imperative that we at

least have a basic idea about what evolution actually is.

Very simply and generally put, evolution is the development of new species [2] from pre-existing ones.

Put differently, it is the descent of new species with gradual modification of its earlier traits. Byextension, another meaning of evolution is common descent: the idea that alllife forms gradually

developed from the same ancestral being. So the first definition is very general in that it describes a

natural process i.e. descent with modification that is generallyknown to occur. Common descent

employs a more restrictive definition, and claims all the extant species were necessarilyformed via

descent with modification. More will be said on this in a later section.


2/12

We will first examine the general evolutionary process of descent with modification. It should be noted,

however, in order to make this essay universally accessible, the discussion is kept as simplified as

possible and technical terms have been introduced very sparingly. Also, brief philosophical

interpretations of scientific phenomenon has been introduced when needed, however such expositions

are tangential and will be discussed in greater detail in the next sextions.

The idea of gradual descent of living creatures from their pre-existing counterparts is older than we

might think, traces of this idea are found with ancient Greek thinkers like Anaximander and Empedocles.

However, Charles Darwin was the first to develop a plausible naturalistic mechanism for it. For Darwin,

evolution relied on a process he termed natural selection. How does natural selection work? To answer

this, Darwin pointed to the birds of Galapagos.

The Galapagos is a chain of volcanic islands in the Pacific. Of the diverse array of birds, reptiles and

animals found here, what particularly attracted Darwins attention are the finch birds, which vary subtly

in their physical constitution and the shape of their beak.

Figure: Different species of finch birds vary in their beak constitution.

Darwin noted, sometimes a nuanced beak grants a finch species an edge over the other finch

varieties. For example, during seasons following heavy rain, small, soft seeds are plentiful in the island,

and thus are readily available to birds with small beaks. However, during times of drought, the seeds

available in the island are encased in hard shells. The only birds with access to this food source are those

with longer beaks. As for the birds with small beaks, they die out due to starvation. So in this scenario,

the birds with long beaks have a functional advantage over birds with smaller beaks. If the drought


3/12

condition continues, the bird population will contain an increasingly higher percentage of birds with long

beaks, as the birds with smaller beaks continue to die out. In other words, this trait of long beak will be

preserved in the bird population, and will be passed down to successive generations. So here we see

that it is as if nature is passively selecting the trait that will survive. Darwin argued, if enough number

of such traits accumulated in a species, a point will come when this species will be completely different

from its predecessor. Given enough time, all forms of life, unimaginably diverse though they may be, can

be plausibly explained in terms of natural selection.

Note that the process of natural selection does not create or produce new traits, much less species.

Rather, it passively works on already existing traits, preserving the functionally advantageous ones and

rooting out others. In our example of bird beaks, the traits long beaks and small beaks were already

there, all that had to be done is for the prevalent natural condition (i.e. drought) to be such that only the

long beak trait would survive. As a matter of fact, natural selection does not have any causal potential,

rather it is a convenient way of describing some integrated factors of relevance e.g. natural condition,

survivability etc. So the question arises, if natural selection doesnt create new traits, but only passively

selects it, then what is it that does? For example, how is it that there were birds with long beaks to beginwith?

Darwins contemporary science didnt have an answer to this, so Darwin- perhaps justifiably- attributed

the development of new traits to chance. Note that chance, like natural selection, isnt really a causal

agent; rather in this context it is a confession of ignorance. By saying new traits emerge by chance,

Darwin did by no means claim that chance is causally responsible for the creation of new traits, rather

what he meant was we dont know how new species emerge. Thanks to advancements in genetics and

molecular biology, we now have an answer to what accounts for development of new traits.

All known living organisms have a specialized strand-like molecule in their cells, referred to as the DNA.

This molecule can rightly be referred to as the information molecule, for strange as it may sound, this

single molecule contains all the instructions as regards the structure and function of an organism[3]. This

information is coded in the DNA in the form of 4 building block molecules (nitrogenous bases). This

encoding of information is strikingly similar to how a computer program works. Much like how a

computer stores information in an alphabet consisting of 0 and 1, the DNA stores information in an

alphabet with 4 letters arranged in a meaningful sequence [4].


4/12

Figure: Left: a ball-and-stick model of the DNA molecule. Right: the bases of DNA which comprise its

four-letter alphabet. The letters are arranged in a meaningful sequence in the molecule to constitute

the blueprint of life.

How this information is translated to collectively constitute the structural and functional characteristics

of the body is a very complex and intricate discussion. Thankfully however, this is of little relevance to

our current topic. All that needs to be kept in mind is, since the information in the DNA is translated into

bodily characteristics, any change in the information content of the DNA may result in changes of the

traits themselves. This gives us a clue as to how new traits may generate in an organism: if there is

change in the DNAs information content, then there would be change in the connected physical trait,

and altogther new traits may develop. This however doesnt answer the question of origin of new traits,

merely pushes it back a notch. Instead of asking how does new traits emerge? we now face the

question how does changes in DNA sequences occur?

The DNA is significant not only in that it is the information molecule, but also because it is of hereditary

consequence. DNA is passed down from parent to offspring by means of reproduction. Of course, the

DNA is not simply drained from the parent and handed to the offspring, leaving the parent DNA-less;

rather identical copies of DNA are made in the cell and one copy is passed down. Due to its relative

simplicity, bacterial reproduction is a convenient setting to understand these processes. Bacteria

reproduce by means of a reproductive mechanism called binary fission, which consists of a single cell

being elongated first, and then splitting into two identical daughter cells. Prior to this splitting, an

identical copy of the DNA molecule is made, and each copy enters the two daughter cells. This process

of DNA-copying is called replication. Although replication is a very accurate process (it has a proof-


5/12

reading mechanism), there is a very small possibility of error in copying. Sometimes letters in the DNA

sequences are randomly misplaced (e.g. an A instead of a T), sometimes a length of DNA is inverted, and

so on. Now although the possibility of these errors is ridiculously low, it is still a non-zero possibility (1 in

100,000,000), and given enough time and generations, it is not unlikely to find such errors. These errors

are called mutations. Besides copying errors, another source of mutation is damage of the DNA by

environmental conditions, like exposure to ultraviolet radiation.

Mutations are almost never a good thing. If someone makes a random mistake while copying, it is very

unlikely that it will somehow render the copied text better than the original in any way; it is vastly more

probable that it would constitute a nuisance e.g. a spelling mistake. With DNA, the case is much more

serious. Since the structure and function of the body depends upon the sequence of bases in the DNA,

any error in copying this information is likely to spell trouble for the body. It is hardly surprising, then,

that many of the fatal diseases are genetic in nature. However, given enough generations, positive

mutations e.g. mutations that are somehow beneficial for the organism, might show up. The most

common example of this is the well-known phenomenon of bacterial development of antibiotic

resistance. In a population of bacteria subject to antibiotic treatment, a change may feasibly happen inthe region of the DNA that codes for antibiotic resistance (mutations tend to be more common under

harsh environmental conditions). Recall from our earlier discussion on natural selection that if such a

new trait confers a functional advantage to an organism, then natural selection will preserve it.

Antibiotic resistance is obviously a functional advantage for the bacterial cell under antibiotic treatment,

and therefore nature selects for this trait and preserves it in the population[5]

. As a result, mutant,

antibiotic resistant bacterial populations develop. This is a plausible solution to the riddle which

confronted Darwin: mutation can account for novel traits in an organism.

Mutations are said to be no more than random, chance variations in the DNA sequences. What does

chance refer to in this context? Stephen C. Meyer explains:

When scientists say that something happened by chance, they do not usually mean to deny that

something caused the event in question. (Some interpretations of quantum physics would stand as an

exception.) Instead, they usually mean that the event in question occurred because of a combination

of factors so complex that it would have been impossible to determine the exact ones responsible for

what happened or to have predicted it. Imagine that I roll a die and it turns up a five. That outcome

was caused or determined by a number of factorsthe exact force applied to the die, the orientation

of the die as it left my hand, the angle at which it first hit the table, and so on. Saying that the five

turned up by chance does not deny that the event was determined or caused by physical factors, but

instead that the exact combination of physical factors was so complex that we cannot know them

exhaustively and, therefore, could not have predicted the precise outcome.[6]

The important take-away point here is, the expression chance/random mutation doesnt render

mutations indeterminate, rather it only denotes a confession of ignorance. True randomness entails a

totally indeterminate process, which mutations are not. There are indeed complex underlying molecular

factors which lead to mutation, but they are so complex that exactly determining them is not feasible.

Therefore, mutations are not necessarily blind as are often construed, they are indeed determinate.


6/12

We may not be able to exactly circle what determines them, but thats a defect in our knowledge and

not a reality of nature. We will get back to this discussion in a later section of this article.

So to tie this discussion to the big picture of natural selection by means of summary, mutation is

responsible for physical changes in the organism. If such changes confer any functional advantage to

that organism, for example access to food source or defense against inhibitory conditions, then thesetraits- and consequently the organisms who posses them- would become more prominent in the

population. With successive accumulation of such new traits, a point will be reached when the organism

will become a different species altogether.

Types of Evolution

With a basic idea of the evolutionary mechanism now behind us, we can examine how evolution is

implemented in nature, with examples of each case. For simplicitys sake, evolutionary workings in

nature can be addressed at different levels:

1. Microevolution. As discussed earlier, a new trait may feasibly develop in a population of organismsdue to the mutation-natural selection mechanism. However, this new trait often only results in varieties

within the same species, as opposed to producing a new species altogether. When antibiotic resistance

develops in a bacteria, it does not transform the bacteria into a different bacterial species, just a mutant

strain of the same species. This phenomenon of intra-species evolution is called microevolution.

Instances of microevolution are all too common, and we observe them directly. A very popular example

of microevolution is selective breeding of dogs, cattle, poultry and so on, which result in varieties within

the same species i.e. different types of dogs, healthier meat producing animals etc.


7/12

Figure: Due to selective breeding, different varieties of dogs have been produced. However, all of those

varieties still fall under the umbrella of one subspecies of domestic dogs: Canis lupus familiaris. This is an

example of evolution within the species i.e. microevolution.

2. Macroevolution. Also called primary speciation, macroevolution refers to evolution above the species

level. When changes in an organism are big enough to bridge the inter-species barrier and produce a

new species altogether, the phenomenon would be called macroevolution. In contrast to

microevolution, macroevolution can almost never be observed directly, because the time it takes for

enough traits to accumulate and produce an entirely new species is too long. Bacteria however, due to

their short generation time, are a promising aspect of study in this regard. An instance of

macroevolution was said to be recorded in the laboratory of Michigan University microbiologist Richard

Lenski[7]

, where E. colibacteria developed the ability to utilize citrate as a food source. It has been

claimed that this new trait is significant enough to count as macroevolution i.e. the new citrate-utilizing

bacteria are not merely a variant ofE. coli, rather a species completely different from E. coli[8]

.

It would be useful to briefly contrast microevolution and macroevolution to develop a deeper

understanding of the two ideas. Macroevolution may appear to be an extension of microevolution in

that the difference between them is only quantitative. Microevolution asks for small changes within a

narrow limit, while macroevolution envisions changes big enough to surpass the inter-species barrier.

Due to the modest claim microevolution makes, it is completely uncontroversial and directly observable.

Macroevolution, on the other hand, has scarce direct experimental evidences. This is not a flaw on the

theorys part though, because macroevolution does advance enough scientific evidences to assume a

scientific status.


8/12

3. Common descent. While macroevolution describes a plausible process through which organisms

couldor are known to evolve, common descent categorically claims that this is the process through

which all organisms didevolve. Put differently, common descent generalizes the evolutionary

mechanism for all forms of life. There is a qualitative difference between macroevolution and common

descent, in that macroevolution states a scientific process, but common descent states a historical fact.

We are not saying that any of this somehow discounts the warrant for common descent, for all we know

the generalization may be a valid one, and scientists have indeed advanced evidences to support this

theory. An interesting question here is, can someone accept macroevolution yet reject universal

common descent? It is hard to see why not. Surely it is at least plausible that some organisms evolved

while others did not. So common descent is not a direct, much less necessary implication of

macroevolution, rather it is a qualitatively and quantitatively different from the latter.

The tree of life is a direct implication of the theory of common descent. It shows how all life forms,

including man, share a common ancestor. The branches of the tree represent the divergence of new

species from pre-existing ones via natural selection.


9/12

Figure: The tree of Life.

4. Origin of Life. Darwins Origin of species deliberated only upon how new species were formed from


10/12

already existing prior species. As for the question of the first life or evolution of life form non-life,

Darwin had precious little to say. Subsequent scientists like Thomas Huxley and Ernst Haeckel did not

deem this issue very significant, which was due to their lack of knowledge of the intricacies of cellular

structure and mechanism, and also perhaps because of their commitment to naturalism. However, with

advancements in biochemistry and molecular biology in the 20th century, the true complexity of the cell

and its diverse mechanics revealed itself in full glory, and the challenge of explaining life from non-life

via natural processes seemed all too real. The evolution of life from non-life stands distinctly apart from

other forms of evolution. This is because the evolutionary mechanism of mutation-natural selection

detailed above only applies to biological entities capable of growth and reproduction, not prebiotic

chemicals. Still, this issue almost invariably comes up in discussions about evolution. Whether it is a part

of evolutionary biology or not is a semantical dispute, and need not concern us.

Evidence for Evolution

As a conclusion to the scientific discussion of evolution, it would be beneficial to look at the evidences

suggested for evolution. As noted in the abstract, the article asserts that the evidences for evolution are

valid. Hence, we will not enter a detailed synopsis of the evidences, and simply list them.

From the foregoing discussion, we find that evolution makes the following claims about reality.

1. Through mutation and natural selection, changes and variations occur within a single species.

2. Through successive mutations and natural selection, a species develops into an entirely different

species.

3. All forms of life evolved from pre-existing forms of life, and an universal ancestry can be traced back

to the first life.

4. The first life arose from nonliving chemicals through natural processes.

As for (1) i.e. microevolution, it is a commonly observed phenomenon, and therefore as certain as any

other fact about nature e.g. plants produce oxygen. As for (4) i.e. origin of life, the debate is not about

whether life didoriginate from non-living chemical matter through natural processes, rather it is about

whether such an event mayplausibly happen or not. If it does seem plausible that life could evolve from

prebiotic chemicals, there is no reason to go for an alternate hypothesis, scientists contend. The field of

chemical evolution seems very controversial, while certain hypotheses do show promise, we do not

have a rigorous theory for the spontaneous origin of life from non-life yet. Again, this hardly concerns us

since we are asserting that the evidences for evolution are valid.

Things get more interesting as we look at (2) and (3), which are macroevolution and its generalized

implication common descent, respectively. As noted earlier, both of these are very lengthy processes,

and thus it is not feasible to observe their functioning in a laboratory. However, indirect evidences have

been suggested for them, for example:

1. The fossil record has been interpreted to denote evidences for common ancestry, while divergences

of fossilized traits denote the branches of the tree of life i.e. development of new species. The human

fossil record contains several extinct species of the same genus Homo, for example Homo


11/12

neanderthalensis, Homo erectus and Homo habilis.

2. Anatomical homology or similar features of living creatures suggests that they share a common

ancestor. For example, the forelimbs of bat, porpoise, horse and human are homologous.

3. Molecular phylogeny or similarity in genetic material implies common ancestry, which is possibly the

most popular evidence today. For example, the base sequences of human and chimp DNA are 98%

similar.

4. Vestigiality or the existence ofuseless (vestigial) organs like appendix or the fifth toe imply that

these traits were possessed by our evolutionary ancestors, but they gradually lost their function.

5. Similarities in early embryological stages between different animals suggest that they share a

common ancestor.

These are possibly the most well-documented evidences for common descent. With this, we close the

scientific discussion on evolution.

Notes and Bibliography

1. For more information, see Bradley Montons Seeking God in Science: An Atheist Defends IntelligentDesign.

2. A species is, simply defined, an unit of living creatures with a high degree of similarity. Apparently

there is some disagreement about the biological definition of a species. It is popularly defined as a group

of living organisms who can engage in sexual reproduction to produce fertile offspring. For example, a

horse and a donkey can procreate to produce a mule. A mule, however, is not fertile i.e. not capable of

producing offspring. As such, a horse and a donkey are not of the same species. Things get more


12/12

complicated when we get to the organisms that are not able to reproduce sexually, e.g. (some, but not

all) microorganisms. For microorganisms, species is defined on the basis of morphological and

biochemical characteristics, and degree of similarity in genetic material.

3. For some viruses however, it is the RNA that acts as the information molecule, not the DNA.

4. Adenine, Guanine, Cytosine and Thymine; usually referred to by their initials i.e. A, G, C and T.

5. This portrayal is accurate for single-cells bacteria only. For multicellular life like animals and plants,

the issue is much more complex. However, the general theme is uniform in both cases, namely that

mutations account for changes in traits and positive traits are preserved.

6. Stephen C. Meyer, Signature in the Cell.

7.http://en.wikipedia.org/wiki/E._coli_long-term_evolution_experiment

8. This claim has not gone unchallenged however, see

http://www.evolutionnews.org/2011/09/richard_lenskis_long_term_evol051051.html
http://en.wikipedia.org/wiki/E._coli_long-term_evolution_experimenthttp://en.wikipedia.org/wiki/E._coli_long-term_evolution_experimenthttp://en.wikipedia.org/wiki/E._coli_long-term_evolution_experimenthttp://en.wikipedia.org/wiki/E._coli_long-term_evolution_experiment

Evolution and stuff...

Documents

Transcript of Evolution and stuff...