Resolving Human Evolutionary Dating Dilemmas

If you listen closely to newscasters, schoolteachers, and evolutionary experts when they talk about our evolutionary history, you will notice discrepancies in the numbers they quote. Do those discrepancies bother you? Or do you, like many people, simply hear another really big number and move on with your day? Well, those discrepancies are pretty big, and they bother scientists who are concerned about the accuracy of their claims.

Now keep in mind that evolutionary scientists are not in the habit of questioning whether or not apelike-creature-to-human evolution occurred. Nor are they in the habit of attributing the sorts of differences that distinguish us modern humans from Neanderthals to a cause any different from that which makes us different from our supposed ape cousins. But, with complete confidence that we are the products of millions of years of evolution, they would like to know when the key events in our evolutionary history happened.

To that end, the Guardian recently published an in-depth article summarizing the human-dating dilemma and announcing its imminent resolution. The publication titled this celebration of an apparent evolutionary victory “Why We’re Closer Than Ever to a Timeline for Human Evolution.”1

Let’s have a look at the molecular clock credited with resolving the timeline and see if, as the Guardian proclaims, we really are “closer than ever to a timeline for human evolution.” Are we, as the Guardian claims, nearly ready to salute a chimp and know “the correct number of ‘greats’”2 between his great-great-so-many-greats grandpappy and ours?

Two Dating Dilemmas

The discrepancies that disturb evolutionists focusing on human history involve the timing of two key events—the supposed split between chimp and human lineages and the divergence of the Neanderthal variety of human from the modern human lineage. Let’s examine the big picture, as seen from the evolutionist’s perspective.

Evolutionists maintain that life evolved as a single cell, our last universal common ancestor (LUCA), billions of years ago. Life then evolved multicellularity and ever-greater complexity, ascending up the diverging tree of life until Old World monkeys and apes diverged from a common ancestor 25–30 million years ago. Then apes split into lesser apes (like gibbons) and great apes. Some of the great apes evolved the ability to walk upright on two legs. This bipedal innovation presumably paved the way to the human lineage and therefore represents an important milestone. This major split between the chimpanzee’s ancestor and our more bipedal one is commonly dated at 6.5 million years. However, a while back, data derived from different methodology doubled this age, suggesting the supposed chimp-human split occurred 13 million years ago. That’s inconvenient!

Further along the evolutionary path, past clearly nonhuman creatures like the iconic Lucy, some supposedly “not-quite-human” creatures appear, people like Neanderthals and Denisovans. Observable scientific evidence—ranging from the anthropological to the architectural and from the anatomical to the genetic—has made it clear that Neanderthals and their near relatives are just extinct varieties of humans, not all that different from us. Yet compared to modern humans, there are some differences. When did our lineages part ways? Depending on how the split between them and the genetic road that led to us is dated, numbers vary from around 300,000 to around 600,000 years. That’s a pretty big difference too.

Molecular Clocks and the Mutations That Make Them Tick

In each case, these discordant numbers—6.5 vs. 13 million years, and 300,000 vs. 600,000 years—come from molecular clocks. The “molecules” in molecular clocks are the DNA in the genomes of the organisms under consideration. DNA molecules carry the coded blueprint of heritable information. Copies of copies of copies of DNA are passed from one generation to the next. The instructions encoded in DNA “tell” a fertilized egg, for instance, how to develop into the mature organism it is designed to be. DNA’s instructions contain many “letters” (called nucleotides), of which some are more important than others.

Mutations—accidental changes in DNA—happen. DNA copying errors can happen in any cell that is dividing. Mutations that happen in the germ cells of multicellular organisms—such as the egg or sperm of mammals—can be passed on to offspring, carrying their effect on to subsequent generations. Some mutations are devastating to a developing organism, some mildly harmful, some even helpful under the right circumstances,3 and some are of no particular consequence. (None, by the way, add information of the sort needed to evolve into a new more complex kind of organism. Mutations, contrary to evolutionary claims, are not the engines of evolution.) How frequently mutations happen is the mutation rate, and mutation rates vary a lot.

Evolutionary molecular clocks have been based on this principle of mutation. For example, in the past, two groups of individuals might have become separated. Once segregated from one another, each group will independently acquire new mutations each generation. If we fast-forward to the present, these two separated groups will look different genetically. If we know the rate at which each group has been mutating, we can assign a date to the time at which they split. Evolutionists apply this principle to the question of when human and chimpanzee lineages split, and to the question of when Neanderthal and modern human lineages split.

Historically, two major assumptions have made this approach flawed at its foundation.

Historically, two major assumptions have made this approach flawed at its foundation. First, evolutionists—believing that all living things share common ancestry—have assumed that mutations are the cause of all DNA differences. From a creation perspective, we know that some DNA differences must be the result of God creating different kinds of creatures in the beginning. Furthermore, within creatures themselves, God created DNA variety. In other words, we know that some DNA differences are not the result of mutations.

Second, evolutionists have rarely measured the mutation rate. Instead, they have calculated an assumed mutation rate by dividing the number of DNA differences by the elapsed time in the supposed evolutionary timescale. In other words, rather than watch DNA change between parents and offspring, evolutionists have assumed a mutation rate from within their worldview.

Not surprisingly, when scientists have directly measured actual mutation rates in the lab, they have found significant discrepancies with the assumed rates. For example, using the old molecular clock method—dividing the number of genetic differences between chimps and humans by the time they supposedly took to accumulate—evolutionists have presumed that the rate of mutation in humans and chimpanzees was six per year.

Direct measurements of the rates of mutation in humans and in chimps have been completed within the last 10 years, and these mutation rates are half of what the evolutionists predicted. Such a slow rate within humans—if applied to the supposed evolution of humans from an ape-like ancestor—would require 13 million years to account for the vast differences between chimps and humans. (We, of course, are not saying this transition is possible, but evolutionists assume that’s the evolutionary journey that created us and calculate how long it presumably took.)

Pinning Times on the Imaginary and the Real

So has this new, more refined mutation rate—gleaned from analysis of the real genomes of parents and offspring—given credibility to the supposed evolution from ape-like creatures into humans? No! This new and improved mutation rate—drawn from observational science—is being used to measure the time it would take for such enormous, unobserved changes to occur. Remember, evolutionists incorrectly assume that humans evolved from an ape-like ancestor by accumulating a massive number of mutations. Note that the measured mutation rate within humans—regardless of what it is—does nothing to lend any credibility to the notion that apes and humans share an ancestor.

Though humans and chimps do not share a common ancestor, modern humans and Neanderthals do have a shared ancestry. After all, every human that has ever lived—including every Neanderthal—is a descendant of Adam and Eve. Comparison of the genomes of modern humans, garden-variety Neanderthals, and the variety of Neanderthals found in Spain’s Sima de los Huesos cave have revealed that modern humans share less apparent kinship with the group in the Sima cave than with other Neanderthals. And because the Sima cave people supposedly lived (and died) 430,000 years ago, evolutionists calculate that early modern humans branched from our shared Neanderthal lineage some time before that.

Genomic comparisons have confirmed a common genetic heritage between us moderns and ancient Neanderthals.

Genomic comparisons have confirmed a common genetic heritage between us moderns and ancient Neanderthals. Genomic comparisons have even refined our understanding of these relationships by showing that the people buried in Sima are more distantly related to us moderns than other Neanderthals. But what of the 600,000-year date? (Actually the now-acceptable numbers are anywhere from 550,000 to 765,000 years, depending on which study you consult, but 600,000 will do for round numbers.) Can we, for instance, trace some aspects of our modern immune system to Neander-cousins 600,000 years ago? To our Neander-cousins, yes; but not 600,000 years ago! Those numbers are grossly inflated because they assume that all differences among descendants of the original humans are due to mutation. In fact, this is likely untrue, as God created the raw material for variation within the DNA of the first two humans, Adam and Eve. In other words, many of the DNA differences between humans are not the result of mutations.

Does this mean that molecular clocks are entirely useless? Quite the opposite! These new, direct measurements of mutation rates in humans and other species are revealing some of the strongest evidence for the biblical timescale.4

“But the Bible doesn’t mention Neanderthals,” some might point out. True. But the Bible also doesn’t mention Americans or Melanesians or Peruvians. Despite no explicit reference to these people, the Bible does contain a great deal about humanity’s early history, information relevant to understanding the place of Neanderthals in that history. All people today have a common ancestor—Noah who along with his three sons survived the global Flood. The Flood is a genetic bottleneck through which all surviving human genomes passed. And from adding up the dates of various events described in the Bible, we know the global Flood happened roughly 4,350 years ago. During the centuries after the Flood, the descendants of its eight survivors finally dispersed, after God forced the issue by confusing their languages at the Tower of Babel. Thanks to God’s Word, a reliable historical account, we know that early modern humans diverged from other varieties of humans like Neanderthals not 600,000 years ago but only around 4,000 years ago. And because both they and we are fully human, no ape-to-man type of evolution was needed, just the variations that occur within the human genome.

Want to get in touch with your real roots? You won’t find them up or under the evolutionary tree and its imaginary history. But you will find a record of your real ancestors—like Adam and Noah—as well as your nonancestors—like the land animals God created the same day as Adam (Genesis 1:24–27)—on the pages of the Bible.