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Genetic entropy and human lifespans

If the human genome is degrading, shouldn’t lifespans be getting shorter?

Published: 15 July 2012 (GMT+10)

In today’s feedback, Dr Robert Carter shows how the increase in average human lifespan over the last few centuries is consistent with genetic entropy, and Dr Don Batten answers a skeptic who thinks that a high-school-level education in biology is sufficient to answer informed creationist objections to evolution.

Leo V. from the United Kingdom writes:


I hear a lot from my work friends that people in the Western countries are living to be older and older. If this is true, this would counter evolutionary theory. Sanford’s book on genetic entropy and Cuozzo’s ‘Buried Alive’ (showing evidence that worldwide we are maturing younger-meaning our life spans should shorten) would demand that our life-spans should shorten.

Is it bad research that indicates man is living longer today? God bless you in you work, Leo

CMI’s Dr Robert Carter replies:

Dear Leo,

You ask a great question. I will do my best to explain.

Consider this set of numbers: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20.
The average of these = 10.

Now consider this set of numbers: 8, 10, 12, 14, 16, 18, 20.
The average of these = 14.

The only difference is that I dropped the first several numbers to create the second set.

This has a direct parallel to human lifespans in modern times. Through the wonders of modern technology, we have figured out how to cure many childhood diseases that used to kill huge numbers of infants and toddlers (cholera, whooping cough, typhoid, small pox, etc.). In essence, we have dropped the highest category of death and moved these people up into the middle of the lifespan distribution. This drastically affects average lifespan, as illustrated in the difference between the two number sets above.

It does not, however, affect maximum lifespan.

Also, we have figured out how to cure, or at least attenuate death rates, for many things that used to kill people in the middle of their lives (heart disease, prostate and breast cancer, etc.). That moves people up into the older category and shifts the average life span upward even farther. It was almost unheard of 100 years ago that someone could recover from cancer and live another 20 or 30 years, but this is now commonplace.

As above, this does not affect maximum life span, even if it does get more people up into the highest category than got there prior to modern medicine.

Third, if humanity is slowly losing its natural lifespan through genetic entropy, it would not be observable in any short time span. It should be expected that the average lifespan for a person in the 1800s should be approximately the same as for a person today, if one could exclude all other factors like diet, disease, accidents, war, etc. This, of course, is impossible to do, so all we can do is look at the historical record and make a best guess.

Doing so shows that people today are living longer. But, this is not due to anything other than nutrition, hygiene, and medicine. In essence, we have learned a lot in the last several hundred years and this is allowing more people to live to greater ages than in the past.

For your interest: Living for 900 years, Decreased lifespans: Have we been looking in the right place?


Dr. Robert Carter

John G. from Australia writes in response to article Question evolution! with comments from Dr Don Batten interspersed:

My science education on biology finished in high school, yet I can answer about 1/2 of these.

Firstly, if you read the linked material that explains each question, you might find the questions are harder to answer than you think.

Secondly, if you read the attempted responses that have been published, you might also find that your proposed answers don’t stack up as you might imagine. We have published the best responses we have received:

You might be interested to know that I wrote the 15 Questions. I have a PhD in biology and over 20 years’ experience in full-time hands-on research. The 15 Questions were also vetted by two other PhD biologists. All our doctorates were earned at secular universities. So you might like to re-think your idea that your high school biology cuts it in being able to answer questions that even high-profile evolutionists with research degrees admit are a problem.

123rf.com/Sergei Popov
Why is it that people seem to link creationism with God and evolution with atheism?

Creation demands a Creator; evolution (Nature created itself) does not.

Disclaimer, I am an atheist, but that’s got nothing to do with evolution.

Thanks for being up-front about that.

There are many many religious people of many faiths that have no problem with evolution.

Of course ‘religious people’ can believe in evolution. The vast majority of the world’s population is ‘religious’ and believe all manner of things. Satanists especially believe in evolution. But I am not really interested in ‘religion’, but in Jesus Christ as Creator, Lord and Saviour of the world. Jesus said that no one comes to the Father but via him (John 14:6). Either he was correct about that, in which case all other religions are false religions, or he was wrong, in which case I should not be a Christian.

In fact one Christian friend of mine said “What better way for God to work then to set up the dominoes and watch them fall down” (referring to evolution).

Yes, I was one of those who thought that evolution might have been God’s way of doing things. But that was before I really thought about the implications. Here is the story of another PhD biologist Christian who recognized the problems also, Dr David DeWitt: Why I rejected ‘theistic evolution’. The following article spells out some of the difficulties in a Christian accepting ‘God used evolution’: 10 dangers of theistic evolution. And this one augments it: Some questions for theistic evolutionists. You might like to share these with your Christian friend and ask for a response.

But I think that the very fact that you have bothered to comment on our Question Evolution campaign indicates that it is not the non-issue for you that you say it is. Indeed, I can’t see how any atheist could be ‘open-minded’ about this. If evolution does not work (and it doesn’t) then atheists are left without the crutch of naturalism to prop up their stated non-belief in a Creator. As Richard Dawkins said, Darwin enabled him to be an intellectually-fulfilled atheist. It’s pretty fundamental to atheism. And I suggest that’s why our campaign bothers you.

Instead of spending money on a silly campaign, you guys really should go out and read some of the science (from real scientists from accredited universities in the field of evolutionary biology).

I suggest you read some more of biology from a creation point of view, from biologists who have real doctorates from accredited universities, on our website. Peer-reviewed papers are published in the Journal of Creation (archived on creation.com). You will find that we are well-read in evolutionary biology, whereas evolutionists are forever misrepresenting creationists (straw man arguments are much easier to dismiss).

With kind regards,

Don Batten

Readers’ comments

Richard B.
I am a board certified epidemiologist (ret). The epidemiologic term for what Dr. Carter is describing is called "the rectangularlization of the population" and has been watched for decades now by health experts. It describes the shape of the population graph when plotting age (x axis) against population in that age group (y axis). What has been noted is exactly what Dr. Carter described using simple statistics. The population graph a century or more ago used to be a slope starting with an acceleration due to infant and childhood mortality and then a fairly steady slope downward - then aymptotically approaching zero around 80-90+. Now the shape in the western world looks like a rectangle - short, brief acceleration (still infant mortality) then little drop off until in the 60s+ and then an increasingly sharp decline to the same asymptotic parameters approaching the 80s and 90s. It has been observed that the percentage of centenarians has essentially not changed! The population is not living longer, only more people are living to an age which appears to be naturally limited by unknown (genetic?) factors.
Rob Carter

Thank you for adding proper terminology to my simple statistical approach.

- RC
Chandan C.
I think Genesis 6:3 answers the question about human lifespan.

Then the LORD said, “My Spirit will not contend with humans forever, for they are mortal ; their days will be a hundred and twenty years."

Modern medicine, advanced technology, a deeper understanding of how the human body works, new inventions, discoveries, exercise, a balanced diet, the availability of fresh fruits and vegetables, information about nutrition, ability to treat and cure diseases, etc. are all reasons for people living longer and healthier lives. God is omniscient and knows when each of us will pass into eternity. Praise Him for limiting our time here on earth, and for the time that we can spend sharing the gospel.
Rob Carter

The "120 years" statement has often been used to conclude human lifespans were limited to around 120 years just prior to the Flood. However, the statement could also mean there were 120 years until the Flood, giving Noah time to have three sons, for them to grow up, etc. See timing-of-events-noahs-life. Note that people lived for far longer than 120 years after the Flood and that there is no "120-year" plateau in the ages of the post-Flood patriarchs (see biblical-chronogenealogies and consider David's statement in Psa 90:10). Yes, praise God for limiting our time here on this sin-cursed earth, but I am not convinced that the average amount of time should be even approximately 120 years.
Wayne T.
John G has failed to note that evolutionary biology has no answers for origins, dealing as it does with only living organisms. Even Professor Douglas Futuyma, author of the university textbook "Evolutionary Biology" (Sinauer Associates) notes "It is important to ask, though, whether true evolutionary novelties actually arise by mutation. For example, can both a new enzyme and the regulatory system that modulates its production arise by mutation" (p. 252), the good Professor being unable to answer his own question in the affirmative. Unfortunately, evolutionists continue with their usual "bait-and-switch" tactic of redefining evolution when it suits them. The General Theory of Evolution states that all life on earth arose from a single common ancestor which itself arose from an inorganic form. Evidence that does not support that hypothesis directly, such as adaptation and genetic drift, is circumstantial and may in fact be evidence for an alternate theory - Divine Creation.
Don Batten
Of course 'cosmic' evolution claims to explain the origin of everything, including the Universe, the Earth, life and all.
Futuyma acknowledges a crisis that modern molecular biological research has caused for biological evolution. We could talk also about meta-information.
Deb B.
I'm concerned with many people now living and sharing their genes - that once would not have - that there will come a time when most people will be born with genetically induced medical issues. The gene pool is degrading because of modern medicine. This must eventually have a major impact on society. As multiple diseases are bred into us - I suspect lifespans will once again drop. It may be an interesting experiment to compare genetic material from people who died in the past, with today - and see if the 'faults' have increased.
Rob Carter
Deb, perhaps inadvertently, but you are hinting at eugenics theory, something we have written much about (see hooray-for-eugenics). Dr. John Sanford has a lot to say about this in his book Genetic Entropy and the Mystery of the Genome (see from-ape-to-man-via-genetic-meltdown-a-theory-in-crisis). Basically, since there are so many mutations, and since all of us carry a huge load, it is mathematically impossible to sort people out into "good genes" and "bad genes". It is also impossible to stop the devolutionary cascade. Even with reduced medical care (stronger selection), mutations will continue to increase. The human race is doomed, except that Jesus promised to return and the Bible clearly indicates there will be people here when He does.
Andrew A.
Actually, for me, it was my High School biology that convinced me that evolution couldn't work. We were studying, in great detail, the many steps that were required for photo-synthesis to work, and I just couldn't figure how such a complex process could originate via evolutionary processes. Our teacher, who was a highly qualified biologist, and an atheist, couldn't answer our questions, so she told us "To pass the exam, you don't have to believe evolution, you just have to write about it." And that is what we did.
D. B.
Can any evolutionist please publish scientific facts - and I mean "FACTS"!!! - to prove that evolution did take place. I am not talking changing within a kind (Darwin's silly observation of the beaks of finches), or any of non scientific "Proofs" of evolution. We simply don't swallow that kind of trash any more. Prove it in a lab - and I'll believe it. In the mean time I will stick with "God created the Heavens and the earth."
Peter V.
Can I point out that the three articles that provide the reasoning against theistic evolution don't address whether evolution is true or not? They advance an argument that evolution shouldn't be true because it diminishes faith and contradicts theology. Since nothing can exist in the world except that God wills it then, if the evidence of the world contradicts theology, we--obviously--have got the theology wrong (in the way it was felt that the world had to be the centre of the solar system/universe because theology "demanded" it). Arguing that evolution must be wrong because it diminishes faith or contradicts our understanding of God's will doesn't address what the evidence tells us. And, if (as you say) the evidence does support creation, then the argument from theology is, at best, redundant and, certainly, irrelevant.

This is independent of a discussion of the arguments themselves, which hardly seem compelling unless you assume that God is a creature much like yourself. For instance, assuming that a Creation beginning millions of years makes God "too distant" doesn't make sense for God, who is eternal and present at all time and all places in a way that people like us (who live tens of years) aren't: You're projecting your limitations on God much as the Greeks assumed that their gods would share their human failings. Assuming that God, who is omnipresent and omniscience can't attend to every sparrow that falls because millions of years and an infinite creation would somehow overwhelm God reflects the same kind of thinking: If I couldn't imagine it, then God couldn't do it. On another note, the idea that God's eternal creation machine (evolution) makes God only the "God of the gaps" is equally unconvincing: some Creator created this whole universe (from setting up Planck's constant to deciding how DNA/RNA would work). That's hardly a gap: it's the source.

Finally, can I say, that dismissing the young man's response with an answer that boils down to "Well, I don't understand what you claim to understand and I'm much better educated than you. If you think you understand this then you're revealing your ignorance" doesn't even rise to the level of "an argument from authority." It's not an argument at all--it's a refusal to discuss the question.
Don Batten
The three articles on the problems of theistic evolution were provided in the context of a website that has over 7,000 articles which deal with why the evolutionary story of history does not stack up.
I have to wonder if you actually read those articles because your points of refutation provide no connection with the arguments presented in those articles. It's as if you had no answers to the points made, so you thought of something else to 'answer'.
Your approach to theology is Scriptura sub Scientia, which effectively denies the divine inspiration of Scripture. If you are a Christian, that is, someone who follows Christ, then you are not following Christ by taking such an approach, because He regarded the whole Old Testament as inspired, even down to the very smallest letters and marks of the Hebrew alphabet. This could be helpful: Timothy tests theistic evolution and Scripture and general revelation.
Finally, I provided ample reading for the young man to begin to get educated about the issues; it was not an argument from authority, but a little 'wake-up' call to try to open a mind to realize that he might just not know as much as he thought he did.
Daniel R.
Methuselah lived 969 years. After the flood, God shortened men's life in this world to 120 years and later to 70 years. Jesus Said unto her, I AM the Resurrection, and the Life: he that Believeth in Me, though he were dead, yet shall he Live: and whosoever Liveth and Believeth in Me SHALL NEVER DIE. Believest thou this? One need to ask themselves where they are going to be in 120 years? It's right around the corner. One doesn't have to believe what Jesus Said but it won't change the Truth which is not defined by what one believes, but is Jesus Christ.
Don Batten
See what Dr Carter said to Chandan C. (below) regarding the 120 years.
Dawnelle T.
I find it interesting how people think they have all the answers from high school biology. I thought I knew all the answers and I certainly believed in evolution when I graduated. It was during post secondary biology classes I learned more about evolution (and the living world in general) and really started to question evolution when I was exposed to the alternate view of creation.

I find the more we learn about the complexity of life the more complex (and cumbersome) evolution needs to become in order to account for all the new details. Like any lie, more lies need to be added and it needs to be modified to account for newly discovered evidence. The truth, however, never needs to change.
Chuck J.
Articles such as this one, for me, are ones which remind me how grateful I am to God for your ministry not only for all the questions that I have had but also for answering questions from others who have questions that I could not answer.
Melki H.
Nice article :)
Jack C.
Yes, you make the correct observation that the maximum life span of mankind has been decreasing since the beginning of time. The confusion by some who think otherwise is because they compare two completely different time-frames, one very long (centuries and more) and the other very short (decades or less). It's like confusing climate change, which occurs over very long periods with weather, which occurs over very short periods.

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