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Feedback 2008
We have had a number of enquiries and emails concerning the recent widely publicized
comments by prominent evolutionist Steve Jones that human evolution has in effect
ceased.
Carl Wieland responds in a general feedback
commenting on the issue.
Steve Jones and the ‘end of human evolution’
Illustration by Tim Newcombe
A fantasy depiction of a future ‘evolved’ human—feathered, armoured, and flying.
Published: 18 October 2008(GMT+10)
It’s not surprising that a comment by a prominent geneticist that ‘humans
have stopped evolving’ is going to cause a lot of buzz. Not only is it about
evolution, with its overtones of death, sex and religion (or irreligion) but this
time it’s not simply some egghead observation on the spotted Mongolian fruit
louse—it’s about our own kind.
Besides, comments like ‘the end of human evolution’ have apocalyptic
doomsday overtones, somehow fitting at this time of global economic chaos.
And Professor Steve Jones should know what he’s talking about, shouldn’t
he? As a geneticist at University College, London, he has not hesitated to grab
the limelight on various evolution issues over the years. See for example
A Whale of a Tale. Or type “Steve Jones” into the search engine
on our website.
Jones has often delighted in attacks on creationists, with sarcasm and ridicule.
But he has also done us a favour. He was the one who provided a delightfully simple
one-liner very useful for creationists to quote when responding to the standard
chimp-human evolutionary claims. It concerns the common belief that chimps must
be almost human, since they share 90-something percent (the exact figure varies)
of their genes with humans. It was Jones who correctly pointed out that ‘bananas
share 50% of our genes, but that doesn’t make them half-human’.
So what about his claim that humans have ‘stopped evolving’?1 Is it just one more attention-grabber?
Background
Over the years other evolutionists have variously claimed either that human evolution
has stopped, or that it still continues. Or even that it has speeded up, according
to
this December 2007 study as reported in National Geographic.
The confusion reigning on the topic is summarized by the title of a 2006 New Scientist
article:
‘Evolution and Us: some say human evolution has stopped, while others believe
it’s going faster than ever. So which is it?’2
Human evolution has neither stopped, nor speeded up. Nor has it continued at the
same pace. It has simply never taken place to begin with.
Contributing to the confusion has been evolutionists’ standard (and often
deliberate) equivocation over the
meaning of the word ‘evolution’. If it is to be defined as a process
capable of turning microbes into microscopists, it’s safe to say on the basis
of much evidence that human evolution has neither stopped, nor speeded up. Nor has
it continued at the same pace. It has simply never taken place to begin with.
For those wanting to have a humanity created without the God of the Bible,3 the mechanisms of neo-Darwinism
are close to the ‘only game in town’. But neo-Darwinism’s mutation
and selection, both factual, simply do not have the capacity for adding all the
new information required, no matter how many gadzillions of years are postulated.
As this site has repeatedly shown, the changes usually cited in support are heading
in precisely the wrong way—downhill, in the direction of decreasing information
overall.4
The two meanings of ‘evolution’
Of course, evolution is often defined as simply ‘genetic change’ or
‘descent with modification’—or ‘change in gene frequencies’.
All meaning much the same thing. That sort of change is an obvious fact. Call it
‘evolution A’ if you like, as distinguished from the whole ‘goo
to you’ scenario, which we could call ‘evolution B’. Flipping
between the two definitions becomes part of a classic ‘bait and switch’
strategy where evolutionists present A in order to gain acceptance of B.
Defining human evolution as heritable changes in human populations (evolution A),
it’s easy to answer the question of whether it is happening now—it is!
Genetic changes in human populations will continue for so long as there are people
in a cursed and fallen world, one in which random accidents happen to genes and
introduce more and more genetic ‘noise’ into the system.
Natural selection in a created world
Even without this ‘noise’, there would be changes from such straightforward
phenomena as natural selection acting on genes that are already there (not creating
anything new).
An example of natural selection among humans: the fact that Pacific Island populations
tend to produce stronger-than-average rugby players. This is very likely because
their ancestors, in one of the many waves of migration post-Babel, crossed huge
stretches of ocean in open canoes. Those carrying more genes for great strength
would be much more likely to survive such a hazardous voyage. Such natural selection
is a simple, logical deduction. But of itself, it cannot create anything new—it
can only get rid of things (in this case, genes for smaller-framed humans).
Photo Wikipedia.org
The Amish can be regarded as genetically isolated, even living side-by-side with
many others.
But selection pressure in humans does not have to be a life-or-death thing, either.
Anything which gives a particular gene a better or lesser chance of getting through
to the next generation will suffice in order to effect some hereditary changes.
And there are many ways in which this can happen. It might even be some socio-cultural
phenomenon in a certain group that gives an individual with certain characteristics
a higher chance of obtaining a mate, for example. Random genetic ‘drift’
and ‘founder effects’ will also occur in people, just as in fruit flies
or elephants. If a small group carrying only a portion of the genes in a given population
goes off and founds a new population somewhere, the individuals in that
new population will be on average genetically different from the pre-breakaway group,
obviously. This is a random effect that does not depend on selection. So it is not
going to cause adaptation to the environment. It can, though, be ‘shaped’
or fine-tuned subsequently by selection (always within the limits of the information
already present).
Further, remixing in various combinations is going to occur, as people intermarry
across cultural and national and linguistic lines. If anything, this would be expected
to happen more frequently in a shrinking, globalized world.
In short, we would expect what we can call ‘evolution A’ (changes in
the genetic makeup of populations) to happen continually, whether in animals, plants
or humans. It is ‘evolution B’ that most people think of, though, when
the word is mentioned. This is the idea that there has been a grand upward progression
over eons of time from one or a few simple life forms to all of today’s creatures
as their descendants.
But doesn’t Jones say it’s stopped?
So what are Jones’ arguments, bearing in mind those two oft-blurred definitions
of ‘evolution’?
-
Founder effects are less likely. Now that we have a large global
(and more globalized) human population, small genetically isolated groups are less
likely to occur, he says.
True, but ‘less likely’ is not ‘never’. It’s hard
to imagine that it would not be happening at all among the 6 billion or so people
on Earth. Remember that genetic isolation does not have to be absolute, and that
it does not have to be geographic. The Amish in America can be said to have a high
degree of genetic isolation from those they refer to as ‘the English’,5 even while living side by
side with them in populated townships.
Jones also says that the increased inter-marriage we mentioned earlier, making us
more of a mid-brown melting pot, is part of the reason why evolution now has fewer
chances of taking place.
However, as pointed out already, such a phenomenon as this increasing intermixing
is itself a major genetic shift that is taking place, and one that is far from over.
So by the normal definition of evolution as genetic change, that is itself evidence
that it has not stopped. (Unfortunately, most would see such a statement as a concession
to the alleged truth of goo-to-you evolution (‘B’), but that does not
logically follow. That would be a bit like saying that evidence of people changing
clothes is evidence that the clothes themselves were not designed, but arose from
rags by a natural process.)
-
Natural selection is virtually non-operative for humans. Jones
maintains that now that we can control things like infectious diseases, the high
death rate prior to the age of reproduction (reproduction is what counts for selection)
is, in the Western world, all but eliminated. ‘Natural selection no longer
has death as a handy tool’, he says.
But natural selection does not only operate via death of the unfit. As already touched
upon, differential reproductive success may occur without any ‘life or death’
issues being involved. And in any case, Jones himself says it involves the ‘western’
(meaning the developed, presumably) world. Elsewhere, there are still hundreds of
millions in daily grinding poverty, with huge rates of mortality in infancy as well
as childhood. So Jones’ approach says more about a developed-world bias than
about reality.
-
Fewer older Dads means not enough mutations nowadays. This seems
to be Jones’ chief point, his eureka in the bathtub, perhaps. Fewer older
fathers are having children, he says. Mutations (inherited genetic mistakes) occurring
in male sperm are going to be more frequent with age, as there are more cell divisions
between ‘the sperm that made him and the one he passes on’. So, he thinks,
with a drop in the number of mutations, human evolution has ground to a halt.
The idea that inherited genetic change has totally halted would require one to believe
that there are no more genetic mistakes of any kind.
But as even Jones acknowledges, we still have chemicals and radiation in our environment
that will enhance rates of mutation. That does not prevent him from proclaiming
the ‘end of evolution’, though. In any case, the idea that inherited
genetic change (what evolutionists are constantly hammering as ‘evolution’
when they are trying to claim it is a ‘fact’) has totally halted would
require one to believe that there are no more genetic mistakes of any kind, whether
in older or younger fathers. In fact, the average mutation rate is estimated to
be a very substantial ‘175 mutations per diploid genome per generation’.6 So ‘evolution A’
is very much alive. But evolution A does not lead to any sort of onward progression.
In fact, insofar as it involves mutations, it accelerates the rate of genetic decline
in humanity. Devolution, if you like.
In summary, then, as far as people are concerned, natural selection still operates,
gene frequencies still change, and mutations still happen.
How can Jones be so mistaken?
Photo Wikipedia.org
If speeding up mutations is better for human evolution, why no volunteers to stand
in front of X-ray machines?
A professor of genetics and environment at a major UK university, as is Jones, is
hardly likely to make puerile mistakes that are so easily exposed. In all likelihood,
Jones is not really talking about ‘evolution A’ (the genetic changes
that are going on all around us). Rather, he is on about ‘evolution B’,
bacteria to biology professors. The sort of evolution that, if real, could have
us eventually transforming into winged creatures, or feeble-bodied post-humanoids
with giant brains. Whatever fantasy science fiction has proposed about humanity’s
evolutionary destiny, it is not any more strange than the belief that worms, germs,
fish, bacteria, grass, snakes and aardvarks all share the same ancestry. It is this
sort of evolution that Jones seems to say has ‘stopped’, otherwise his
claims would appear far too vulnerable.
It’s easy to show that he is right here. We won’t get to see ‘evolution
B’ in our lifetime. But of course the reason is not that evolution B has stopped
happening—it is incapable of happening, and has never happened in the first
place.
Consider, too, the implications of Jones’ belief that the glories of mankind’s
evolutionary progress are being hampered by the shortage of mutations. To be consistent
there, he and other dedicated evolutionists should stand in front of X-ray machines
(and encourage their offspring to do likewise) to speed up evolution for future
generations. Of course, you won’t see too many volunteers for that. The overall
deleterious effects of an increased mutation rate are too well-known. So, to the
extent that there is a decline in the human mutation rate, we should be relieved,
if anything.
The downward spiral
A drop in selection pressure means there will be less restraint on the rate at which
human DNA quality declines each generation.
As genetic copying mistakes occur (and even if they should be a little slower now,
they are still happening in vast numbers) it adds to the total genetic load or burden
on the population. As we copy our genetic information, generation after generation,
there are continual copying mistakes. And existing mistakes are copied to the next
generation. Then another mistake takes place, which is added to that existing batch,
and so on, an ever-increasing load. This is why we all carry many such mistakes,
inherited from previous generations, in our genes. These mistakes are rarely eliminated
by natural selection,7 which
as Jones correctly points out is indeed a little bit less effective now than it
used to be, in certain parts of the world anyway. This drop in selection pressure
means there will be less restraint on the rate at which human DNA quality declines
each generation. Cornell University geneticist and convert to creationism Dr John
Sanford’s recent book, Genetic Entropy and the Mystery of the Human Genome
(see below), is all about this relentless decline. Such an information-losing process
is in line with what one would expect from random changes in a cursed world. It
is the outworking of the same tendency in all natural systems that gives rise to
the description known as the Second Law of Thermodynamics—because disorder
is overwhelmingly more probable than order, information will naturally head down.
Even a defect can occasionally be a benefit, of course. As when
fish or salamanders in caves lose their
eyes. But such a loss of information (specified complexity) going on continually
points to genetic limits to humanity’s future. It is also totally consistent
with the notion that we descended from an original, programmed high-information
state. And it puts drastic curbs on notions of how long humanity can have been around.8
In summary …
Perhaps the publicity-hungry Steve Jones has unwittingly done the cause of creation
and biblical truth a favour yet again. His airing of the issue has given us a reason
to highlight evolutionary spin on the meanings of the ‘e-word’, and
revisit the facts about inherited changes in people. Genetic change is still very
much a part of humanity. But that change is within the limits of the information
originally programmed into our first parents, degraded by the relentless downhill
accumulation of mutations.
Related articles
Related resources
References
- The information about Jones’ claims has been gleaned
from various media outlets, some of them reporting on lectures he has given. For
example,
‘We re as good as we can get, says evolution expert’. Guardian.co.uk,
7 October 2008. Return to text.
- No. 2542, pp. 30-33 Return to text.
- Which is what ‘evolution’ has always been about,
as far back as Epicurus of ancient Greece (his followers get a mention in Acts 17:18) or the Roman Lucretius.
Return to text.
- See for example, Muddy Waters
about natural selection and Beetle Bloopers about
mutation—both factual things but incapable of doing the job evolutionists
want them to. Also see: The evolution train’s a-comin’
(Sorry, a-goin’—in the wrong direction). Return to text.
- The non-Amish people around them. Return
to text.
- Michael W. Nachman and Susan L. Crowell, Estimate of
the Mutation Rate per Nucleotide in Humans, Genetics 156(1):297–304,
September 2000, <http://www.genetics.org/cgi/content/abstract/156/1/297>. Return to text.
- Most ‘mistakes’ are only going to have a harmful
effect if they are inherited from both parents, which means the ‘carrier’
state is not going to be subject to natural selection. Return to
text.
- To avoid emails on the question, this is a ‘big picture’
conclusion; given the variables in rate already discussed herein, it seems impossible
to try to extract an exact ‘age’ for humanity from the data of genetics.
But we already have such a date in the historical records in Scripture, with which
these observations are strongly consistent. Return to text.
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