Quick post on population and human genetics
In Six Days
Why 50 Scientists Choose
to Believe in Creation
The above is the title of a publication in which fifty (out of several hundreds associated with the site) presented evidence to explain their belief in a literal six days of creation and a young earth. I will present excerpts from one of those fifty quickly.
James S. Allan, genetics
Dr. Allan is a former senior lecturer in genetics at the University of Stellenbosch in South Africa. He holds a B.S. in agriculture from the University of Natal, an M.S. in agriculture from the University of Stellenbosch and a Ph.D. in genetics from the University of Edinburgh, Scotland. He currently serves as an international consultant in the field of dairy cattle breeding.
"As a biologist in the field of population and quantitative genetics, I had believed in the theory of evolution for nearly 40 years. During that period of my life, the long-time requirements of the theory did not really concern me. Chance (genetic drift) and natural selection in response to gene mutation and/or environmental change seemed to be logically acceptable mechanisms for the assumed extent of adaptive radiation.
My research involved using biometrical methods of analysis. I was concerned to predict rates of genetic change as a result of applying artificial selection procedures of varying intensities, based on different kinds and amounts of information. The accuracy of prediction of the rate of genetic change can be assessed theoretically and the results can, in many cases and in the short-term, be checked empirically. The change in genetic merit (and associated phenotypic merit) from one generation to the next is due to changes in the relative frequencies of the underlying genes.
Over all those years, because I accepted the “fact” of evolution, I saw no reason to differentiate in principle between changes in relative gene frequency as a consequence of either short-term or long-term natural selection. To me, these forms of selection resulted in just the one simple principle of change in relative gene frequency, and the essence of the theory of evolution is change in relative gene frequency as a result of genetic drift and of natural selection in response to gene mutation and/or environmental change.
When, at a fairly advanced stage of my career, I became a Christian I began to read the Bible reverently and as intelligently as I was able. At that time most of my reading was focused in the New Testament and, as my main concern was to know more of Christ as my Savior, my opinion concerning the theory of evolution remained unchallenged. I did not, in fact, give it much thought.
One day, after I had been expounding on the universality of DNA as evidence for the theory of evolution, my wife, who had been a Christian much longer than I, asked me whether there was any reason for God to have used other genetic systems. Just one simple question, but it stimulated me to ask myself many more.
Was there any reason for God to have created life-forms on the basis of ABC … PQR … and XYZ as well as DNA? Were that so, would it have influenced my belief in the theory of evolution, or would I have interpreted it as a number of independent origins of life?
Was there any reason why God should not have created all forms of life as “variations on themes” and so have provided the observed orderly degrees of genetic and phenotypic resemblance as evidenced in taxonomic classification? Relatives tend to resemble one another in physical, functional and behavioral characteristics. This is a phenomenon which is basic to the science of genetics. The resemblance is due to the fact that relatives, sharing in the common gene pool of a reproducing population, have genes in common. The closer the relationship, the greater is the proportion of genes in common and, therefore, the greater is the degree of resemblance. The theory of evolution assumes a common origin for all forms of life and, therefore, infers that species, genera, families, orders, etc. are genetically related. They all do carry some genes with similar structure and function, yes, but did this imply genetic relationship in the normal, within-species sense, and was one at liberty to assume a common origin for all forms of life? Was there any reason why God should have created different species, genera, etc. in completely different ways and with completely different genes?"
Why, indeed? Dr. Allan goes into depth in the article, which I hope you do read. He presents evidence that requires millions of years for a prehuman chimp-like ancestor to evolve into a human, if indeed something like that ever happened. But allow me to present his portion of population analysis in which he extrapolates the human population back to a beginning point using both genetic and mathmatical training in the process:
"According to the 23rd General Population Conference in Beijing in 1997, the total human population of the earth in that year was assessed to be in the region of 6,000 million, showing that there has been a remarkable increase over the past 200 years. Estimates of the population numbers back to the year 1500 and a prediction for the year 2080 are given in the following table.
| Year | 1500 | 1650 | 1800 | 1900 | 1950 | 1997 | 2080 |
|---|---|---|---|---|---|---|---|
| No. (millions) | 300 | 550 | 1,000 | 1,700 | 2,500 | 6,000 | 10,000 |
Extrapolation further into the past gives the following approximate numbers:
| Year | –2000 | –1000 | 0 | 1000 |
|---|---|---|---|---|
| No. (millions) | 1 | 50 | 100 | 250 |
I find these figures to be in close agreement with what one would expect from the biblical specification after the Flood in 2344 B.C. The assumed existence of thousands of millions of “prehumans” is both physically and scripturally unrealistic."
I believe it is obvious that a non-linear population growth is represented by the human race. Fits and starts have happened as rapid population growth probably occurred during the great warming period but plagues and wars and the little ice age hampered populations in some areas. Overall, the human population growth estimates take us back to around 2500 BC, which is about 4,500 years ago. Based upon the way the human population has been recorded to have expanded during the last few hundred years it is astonishing that anyone could believe that there has been a steadily expanding population for hundreds of thousands of years, let alone millions! No Sigmoidal curvature yet, that is for sure! (Although the United Nations chart predicts the sigmoidal curve to show up in the future).
No one looking at a chart of human population growth would categorize this as a linear chart. Nor would anyone suggest that we have reached stasis. This kind of growth is found in populations that are relatively young and did not begin long ago. Those of you who love math have to know this, I cannot imagine how you can ignore these kinds of numbers and believe that humanity has been around for any significant period of time.
Population growth is just one clue that the Biblical Flood absolutely took place somewhere in the neighborhood of 2500 BC and there are plenty of other indicators. Next post will go into more detail.
With thanks to the Guardian and Radar O'Reilly, linear, cubic, exponential and sigmoidal curves:
Exponential, linear and cubic curves
A sigmoidal curve.
"As O'Reilly points out, in the end those curves always flatten out. They have to; there just aren't enough people, aliens, atoms, quarks to keep growing exponentially all the time. Growth always slows."
But growth has not yet slowed because the human population just hasn't had much time to grow yet.