In the beginning there were nucleotides

[The Leaven – exploring the relationship between science and religion (cont)]

Common arguments by creationists against evolution theory are if humans evolved from apes why have apes not evolved and how is it possible that life on Earth is so diverse even in similar habitats?  One explanation could be that even though life looks diverse all of it is encoded from just four nucleotides.

Nucleotides play an important role in several biological functions, including metabolism, but they are mostly known for being the base units thymine (t), adenine (a), guanine (g), and cytosine (c) in DNA. When arranged into predetermined DNA sequences, nucleotides can have very similar patterns even in organisms that appear morphologically different.  In fact, although humans may seem to look very different from chimpanzees there is only a 1.23% difference in nucleotide divergence.

Science has become an ever-advancing, voracious creature, forever trying to satisfy a relentless appetite of knowledge and discovery. Whereas, religion treads warily, fearful of disrupting the balances of nature that are governed by laws preceding civilised life. Like a badly matched couple, these two different entities seem to have drifted further apart, but at one time they were closely entwined. Theologians were once dedicated to deciphering Gods laws. They believed that unravelling these may reveal why life exists and to what purpose it served.  For instance, in the 19th century the Augustinian friar Gregor Mendel was equally committed to religious endeavour as he was to scientific investigation. By breeding and statistically recording the colour and shape of peas, Mendel was foremost in discovering that characteristic traits were inherited. He was the first to record genetic variation. It is this same variation that enables some members of a species to follow different evolutionary routes.

Advances in science at the molecular level have further reinforced Mendel’s experimental work. The mechanisms of molecular evolution attribute the blueprint of characteristic traits to nucleotide code which, when inherited by offspring, leads to the generation of tissues that cumulatively construct a new individual with parental characteristics. Genetic diversity exists to strengthen the gene pool, allowing the plasticity needed to evolve. If there were no nucleotide diversity between individuals there may be no life, as variation gives organisms the ability to survive changing environments.

Comparing the nucleotide variation in protein encoding genes from a variety of organisms reveals a distinct evolutionary history. This complex science, known broadly as Molecular Phylogenetics, can involve the comparison of huge amounts of electronic data, sometimes reaching many terabytes in volume.  The human genome alone is composed of over three billion nucleotide pairs that contain thousands of repeated regions and single-nucleotide variations or polymorphisms, also known as SNPs. Molecular phylogenetics allows species to be characterised into orders and families not only through physical similarity but also through the arrangement of their nucleotides.

In the book of Genesis, plants were created first, birds and fish appeared on the fifth day, with other animal life, including humans, arriving on the sixth. The order in which animals appear corresponds roughly with evolution theory, fish and birds being more primitive in genetic terms than mammals with humans appearing later. According to the Bible, humans were put on Earth to control the animals that existed in the land and sea, with females being cloned, by the Almighty, from male bone tissue. The genus Homo is thought to have diverged from other primates fairly recently, within the last four to five million years. Therefore, humans are also considered to be at the top of the phylogenetic tree. There is no mention of microbes in the story of creation as their existence only came to light with the advent of microscopy in the last few centuries. Evolutionary speaking they would appear before plants.

Garden of Eden

Garden of Eden – The Garden of Earthly Delights Hieronymus Bosch (circa 1450–1516)

Recent developments in faster high-throughput DNA sequencing techniques, whereby hundreds of DNA strands are sequenced simultaneously on microchips, have enabled whole genomes of organisms to be sequenced at a fraction of the time and cost.  The human genome sequence was completed in 2003 using older methods developed by Sanger in 1980. It took more than 3,000 scientists 13 years to complete and cost of over three billion dollars.  Currently a human genome can be sequenced within weeks for under fifty thousand dollars. Consequently, nucleotide pattern variations from thousands of genomes in a large number of species are being compared at an accelerated rate using SNPs and other molecular markers to further refine theories of evolution. A major focus of these studies in human genomes is the identification of variation that gives rise to genetic diseases such as cancer.  If a small variation in the usual DNA of the human genome can lead to a disease altering the survival of an individual then, understandably, it could give raise to variation that can increase survival too. In the beginning perhaps God created nucleotides, the rest is evolutionary history.

The Sacrificial Lamb.

[The Leaven – exploring the relationship between science and religion (cont)]

There may have been numerous reasons why ancient communities may have performed rituals and sacrifices. Perhaps they needed to address fear, uncertainty, need, respect or gratitude. Whatever the reasons, rituals are still a part of modern life and sacrifices can still form important components to some religious ceremonies, although they are more likely to be symbolic and just a distant reminder of our pagan ancestry. In the era of the Old Testament, sacrifices were a major preoccupation of Hebrew life. It seems evident that they were carried out to avoid uncertainties and as a form of thanksgiving. They were often accompanied by rituals that were performed according to specific instructions outlined in the books of the Old Testament:

When anyone offers an animal sacrifice, it may be one of his cattle or one of his sheep or goats. If he is offering one of his cattle as a burnt-offering, he must bring a bull without defects. He must present it at the entrance of the Tent of the Lord’s presence so that the Lord will accept him. The man shall put his hand on its head, and it will be accepted as a sacrifice to take away his sins.
[Lev. 1.2-4]

The Old Testament is derived from at least four literary sources that span over several decades from 950 to 587 BC. Unavoidably, some information may have been lost or contorted through subsequent translations but the most authoritative form was thought to be the Pentateuch, a word that derives from the Greek language and meaning five scrolls. The Pentateuch was adopted around 400 BC and consisted of the five books: Genesis, Exodus, Leviticus, Numbers and Deuteronomy. The Hebrew word for these five books is the Torah, meaning law or teachings.

The Sacrificial Lamb. Ghent altarpiece by Jan van Eyck,1432.

The Pentateuch mainly describes the story of Moses: his birth, teachings through a covenant with God and ending with his death. It begins with the book of Genesis. This book provides an in depth history of Moses’ pedigree starting with an account of primeval beginnings to how his ancestors came to live in Egypt. The next book, Exodus, recounts the most important event in Israel’s history, the escape from servitude by its people. The Hebrews were led from Egypt by Moses. While in exile from Egypt for killing a slave master, Moses formed a covenant with God. Through using Moses as a mediator, God provided laws and commandments that Hebrews had to follow to avoid returning to servitude. Leviticus, the third book, contained the rules and regulations for performing religious ceremonies in order to honour God. It includes comprehensive details of how sacrifices are to be performed.

The following are the regulations for repayment-offerings, which are very holy. The animal for this offering is to be killed on the north side of the altar, where the animals for the burnt-offerings are killed, and its blood is to be thrown against all four sides of the altar. All its fat shall be removed and offered on the altar: the fat tail, the fat covering the internal organs, the kidneys and the fat on them, and the best part of the liver. The priest shall burn all the fat on the altar as a food-offering to the Lord. It is a repayment-offering. Any male of the priestly families may eat it, but it must be eaten in a holy place, because it is very holy.
[Lev. 7.1-6]

The book of Numbers deals with the story of the Hebrews after they left Mount Sinai. It includes details of two censuses taken by Moses, one taken of those surviving the exodus on departing Mount Sinai and another taken a generation later. The final book, Deuteronomy, is a summary of Moses achievements as the people prepare to occupy Canaan. The main objective of Deuteronomy seems to be in encouraging the people to give thanks to God. This takes the form of a liturgy delivered by Moses to celebrate future harvests:

After you have occupied the land that the Lord your God is giving you and have settled there, each of you must place in a basket the first part of each crop that you harvest and you must take it with you to the one place of worship.
[Deut. 26. 1-3]

Interestingly, this type of harvest thanksgiving has been conserved through religious tradition and is still carried out today.

…in the beginning there was chaos from which evolved order

[The Leaven – exploring the relationship between science and religion (cont)]

The application of molecular archaeology has largely denounced the explanation of creation as proposed by Babylonian type theories recorded in the Old Testament. Several views held at this time have been dispelled by Science. For instance, rain was thought to fall from seas separated from the Earth by a dome structure which the Creator called sky [Gen. 1, 6-7].

Then God commanded, “let there be a dome to divide the water and keep it in two separate places”- and it was done. So God made a dome, and it separated the water under it from the water above it. He named the dome “sky”.

Birds and fish were created on the fourth day, while animal life on Earth was created on the fifth. On the sixth day the Creator placed humans on Earth to control the animals that existed in the land and sea. The order in which the animals appear seems to be fairly logical, fish and birds being further down the food chain than the higher animals with humans at the very top. There is no mention of bacteria and parasites. Evolutionary speaking they should appear before the birds and fish in day three.

So God made a dome, and it separated the water under it from the water above it. He named the dome “sky”. Woodcut by Julius Schnorr von Carolsfeld 1860

Theories involving the spontaneous generation of living beings were widely accepted for centuries. The Greek philosophers Plato and Aristotle in the 4th Century BC held views that contradicted a gradual evolution of life forms. Plato argued that there were two worlds: one was real the other was imaginary. The variations that were present in plants and animals were merely imperfect illusions of an already perfect form. This philosophy was known as idealism or essentialism and ruled out evolution as organisms were already in the form that they were destined to become. Aristotle recognised that organisms could be arranged according to complexity this is often referred to as a scale of nature or scala naturae. He believed that there was an organism at each scale; species were fixed and no evolution occurred. This view persisted for 2000 years and was widely adopted by natural theologists who thought that the Creator had designed each species for a specific purpose.

Linnaeus in the 18th century adopted a filing system for all these species. He was a natural theologian who claimed that he had developed the classification system in order to reveal Gods plan, he clarifies this using the phrase:

Deus creavit, Linnaeus disposuit; God creates, Linnaeus arranges.

During the nineteenth century yeasts were thought to be part of the plant kingdom in the division of Thallophyta because they lacked true roots, stems and leaves. They were eventually classified as fungi because they do not contain chlorophyll or rely on photosynthesis to create energy. Instead they live a parasitic or saprophytic existence, living off the carbon sources supplied by other organisms. Like other species of fungi, yeast can also form spores. In the case of S. cerevisiae these are found in a sac called an ascus this has earned them the further classification of Ascomycetes.

Jean Baptiste Lamarck was one of the first biologists who proposed a theory of evolution in 1809. As curator of the invertebrate collection in the Natural History Museum in Paris, he observed that insects changed gradually over the centuries. He thought that microscopic creatures were at the bottom of evolution and generated spontaneously from inanimate material. Lamarck felt that creatures evolved towards greater complexity and that higher organisms were aiming towards perfection to become completely adapted to their environment. He proposed that organisms adapted continually thereby some aspects of their physiology grew stronger while others disappeared and that these life-time improvements could be passed on to their offspring. Lamarck’s hypotheses have been largely disproved but his views were revolutionary; he implied that species evolved and that they were not fixed. Darwin’s theory of natural selection was to directly challenge the current viewpoint of fixed design. Natural, or should it be supernatural, theology, was the accepted way of thinking and doing science, each species being allocated a specific niche by a supernatural being.

At an early age Darwin was already a keen naturalist and obtained a degree in theology at Christ College Cambridge where he became the protégé of the botanist Professor Henslow. When he was 22 he joined the crew of The Beagle, a survey ship whose mission was to chart the South American coastline. During this voyage he collected flora and fauna while others surveyed the coast. He was particularly interested in the diversity of species that were present in the Galapagos Islands and recovered over a dozen different types of Finch. Darwin began to understand through his own work, and that of others, that the origin of new species arose from a distant ancestor by the gradual accumulation of adaptations. He saw this within the beaks of the finches that he had collected from the Galapagos Islands. Each Finch had a specialised beak that was adapted to forage for the type of food found on its island of origin. This was visible evidence that selection through environmental factors could contribute to speciation.

Darwin’s drawings of beak variation in Finch species.

Darwin was reluctant to introduce his theories publicly because, being a theologian, he was aware of the controversy that this would cause. He wrote an essay on the origin of species in 1844 that remained unpublished until 1858 when extracts from it were presented to the Linnaean Society. In the same year another naturalist, Alfred Wallace published a paper on the evolution of new species. This prompted Darwin to complete his book the Origin of Species, which was published the following year. The Origin of Species presented a strong argument for natural selection through scientific evidence and became adopted by evolutionists as the primary text on the subject. At the time molecular genetics and the true nature of genetic inheritance were still undiscovered so Darwin adopted a Lamarckian approach to explain acquired characteristics. Where strengths acquired during the course of a life-time could be passed down to the next generation.