Tinkering with the molecular clock: which assumptions should we accept?
Do you have a temperamental clock in your house? A timepiece you hang onto for sentimental reasons even though you have to frequently adjust it to match a more reliable standard, like your cell phone or your atomic clock?
Evolutionists have long debated the various conclusions drawn from molecular clocks, the archaeological record, and the fossil record regarding the timing of early human demographics. “Like bloodhounds on the fading scent of an escaped convict,” writes Ann Gibbons in Science, “researchers have tried for decades to trace the ancient footsteps of the first modern humans who left Africa.” The latest refinements to the molecular clock, reported in Current Biology, finally make these three sources of dates sing the same song. But how reliable are these conclusions?
At issue is just when anatomically modern humans (as opposed to Homo erectus humans or Neanderthal humans, for instance) left Africa where they presumably evolved. While archaeological and fossil estimates had placed this exodus at 80,000 years or less, refinements in the molecular clock based on measurable mutation rates in modern living humans rolled the clock back to 90,000 to 130,000 years.
Molecular clock calculations depend on a constant mutation rate and some sort of standard by which the “clock” is calibrated. University of Tübingen evolutionary geneticist Johannes Krausse doubted whether modern mutation rates—assuming that they’re accurate—are applicable to people living long ago. If they are not, then the latest roll-back to the time humans presumably migrated out of Africa would be invalid.
To assess this, Krausse’s team sequenced mitochondrial DNA from ten fossils of anatomically modern humans, ranging in estimated age from 700 to 40,000 years. By comparing the mitochondrial DNA in these fossils to each other, they recalculated the time of the evolutionary exodus. “Our clock yields mitochondrial divergence times that are in agreement with earlier estimates based on calibration points derived from either fossils or archaeological material,” they write.1 They report that early evolved modern humans exited Africa 62,000 to 95,000 years ago.
Other experts commenting on the study, while noting that it is a clever approach, are not quite ready to discard more recent estimates that are based on nuclear DNA, not mitochondrial DNA. Geneticist Aylwyn Scally of the UK’s Wellcome Trust Sanger Institute notes that mitochondrial DNA may not have the same mutation rate as nuclear DNA.
“Out of Africa is one of the major events within human evolution,” Krausse says. “We need to know when it happened.” Krausse hopes that it will be possible to get more data on ancient nuclear DNA in the future to evaluate these results.
In addition to the data about timing, Krausse’s team also determined that fossils from pre- and post-Ice Age sources in Europe were of the same lineage. This of course is no surprise to Bible-believers, as we know from biblical history that all people alive today descended from Noah’s family. The pre- and post-Ice Age people in Europe were descendants of people who settled there after the dispersion from the Tower of Babel.
But what of the “when” assertions? In addition to the problems noted by evolutionists themselves—the questionable validity of modern mutation rates given the present state of technology and the fact that mitochondrial rather than nuclear DNA is being assessed—there are additional issues that invalidate both the 130,000 year and the 95,000 year estimates. The new molecular clock revisions comparing ancient DNA from ten fossils require the actual age of the ten fossils be known. And the ages of those “securely dated ancient modern humans”1 are estimates based on the unverifiable assumptions underlying conventional interpretations of radiometric data.
Furthermore, molecular clock assessments about humans also are inextricably tied to the belief that humans evolved from ape-like ancestors.
Thus, as “clever” as Krausse’s technique is, in that it gets rid of confusing data from modern living people, the information cannot be relied on to get either the time ancient human populations diverged or the mutation rate of ancient modern humans. Like the temperamental clocks in our homes, we can only set them or even assess the rate at which they lose time based on a reliable standard. Atomic clocks and other modern innovations are based on scientific measurements observed in the present. But clocking the changes in the human genome requires one to make assumptions that depend on some reliable witness to the past. And that reliable testimony is found in the Bible, where we learn that God created man and woman in His own image—not through evolution—about 6,000 years ago and that their descendants—Noah’s family—produced people who dispersed from the region of the Tower of Babel to populate our planet.
Never take your theology from a chimp.
Prominent primatologist Frank de Waal of the Yerkes Primate Center has, on the basis of his observations of primates, shared with the world his answer to the question, “Where did morality come from?” De Waal is an atheist but doesn’t mind it if other people cling to religious ideas because he believes religious ritual strengthens community ties. His book, The Bonobo and the Atheist, asserts that morality evolved as humans evolved. He further holds that humans eventually invented religion in order to codify a blueprint for moral behavior.
De Waal, having observed chimps and bonobos for years, says that they display empathy, fairness, altruism, grief, and guilt. De Waal writes, “Some say animals are what they are, whereas our own species follows ideals, but this is easily proven wrong. Not because we don't have ideals, but because other species have them too.” Thus in the usual approach taken by evolutionists in explaining biological similarities, common designs are claimed as evidence for evolution rather than for a common Designer. Thus, de Waal believes that apes possess the “basic building blocks” for morality, those “seeds of morality” that flowered in humans evolving from ape-like ancestors.
De Waal does not claim that chimps are actually moral, as they are often extremely violent with each other and with humans. They “are ready to kill their rivals.” And “they sometimes kill humans, or bite off their face.” Therefore he is “reluctant to call a chimpanzee a ‘moral being.’” He seems, on the other hand, to rather admire the bonobo “morality” that frequently turns warlike posturing into an orgiastic party.
Nevertheless, he writes, “There is little evidence that other animals judge the appropriateness of actions that do not directly affect themselves. In their behavior, we recognize the same values we pursue ourselves. I take these hints of community concern as a sign that the building blocks of morality are older than humanity, and we don't need God to explain how we got to where we are today.” Note here that de Waal is considering human beings as animals too, just the sentient sort that can judge the appropriateness of what they do. This error—the view that humans are merely highly evolved animals—is the root of de Waal’s erroneous position.
Evolutionists generally believe that the fact that we exist is self-evident proof that we evolved from simple ancestors through a long process of molecules-to-man evolution. Likewise, the fact that humans have a sense of moral judgment and standards of moral behavior is taken as prima facie evidence that such morality is also a product of evolution. The question for the evolutionist is not “whether” evolution occurred but to trace its steps. Thus, as an atheist and an evolutionist, de Waal is musing about which came first, morality or belief in God. But he never considers the possibility that an actual Creator created morality and life, and all that is.
Because apes sometimes exhibit behavior we would interpret as guilt or shame, de Waal concludes that human morality springs from within and that somewhere along our evolutionary path we evolved a religious tendency in order to effectively apply that moral sense to regulate society. De Waal claims, “The moral law is not imposed from above or derived from well-reasoned principles; rather it arises from ingrained values that have been there since the beginning of time.”
Well, those “ingrained values” have been present in humans since God created our first parents about 6,000 years ago, but not because morality evolved. On the contrary, God created Adam and Eve in His own image and therefore with both an understanding of what was good and the choice to obey their Creator or to rebel against Him. Humans have not lost that sense of right and wrong, and we usually call that sense a conscience. Romans 2 explains how the moral standards people tend to impose on others proves they have a concept of right and wrong for which they are responsible, and that moral standard comes from the law of God expressed in the Ten Commandments in Exodus 20 and written on every human heart (Romans 2:14–16). But our propensity to ignore our conscience and sin leaves our moral sense—our conscience—marred, sometimes even seared (1 Timothy 4:2). Romans 1:18–28 indicates how the process of sinful rebellion hardens people’s hearts against godly morality.
Our sinful natures and our marred perception of right and wrong make our conscience an imperfect guide to morality. Therefore, we need the Word of God to truly know God’s authoritative standard by which each of our consciences is judged. As our Creator, God alone has that moral authority.
Humans have a great tendency to anthropomorphize animal behavior, interpreting animal actions in accord with our human thoughts. But animals are not human, as de Waal acknowledges. They do not actually abstractly judge the appropriateness of their actions. If the nature of the animals or the conditioning imposed by interaction with humans or animals produces behaviors we can label in human terms, we should recall that the abstract interpretations are our own and prove nothing about the moral status of the animals. Neither do such moral-mimicking animal behaviors prove anything about our moral origins. If we want to know why we have a conscience, a moral sense, then we only have to look at the eyewitness account of our origins provided by our Creator. And if we want to know whether there is a universal standard of morality, we should understand that the Creator of all people provided a single standard authoritative yardstick of morality in the Bible (Micah 6:8). Since we all—everyone of us—fall short of that perfect moral standard God demands, God has graciously made forgiveness for our sin available through the sacrifice of Jesus Christ.
Jurassic embryos suggest rapid growth of sauropod embryos.
Most known dinosaur eggs have been excavated from Cretaceous rock layers, but scientists examining a square meter of an outwash from a hillside in Lufeng, Yunnan Province, China, are excited to report their analysis of a much older batch of miscellaneous disarticulated dinosaur embryo bones and eggshells. They report these embryos are associated with 195 million year old early Jurassic rock, about 125 million years older than previously discovered dinosaur eggs.2 Because this batch of fossils contains bones at a variety of developmental stages, they can draw some conclusions about dinosaur embryology. Their analysis suggests these sauropod bones belonged to the fastest growing vertebrate embryos known to history.
Appropriately named Lufengosaurus after its place of discovery, the researchers report long-necked sauropodomorph dinosaurs like these reached about 30 feet in length as adults. (The much larger sauropods grew to 200 feet.3)
“They were the biggest things that lived in the neighborhood,” says lead author Robert Reisz, though no complete skeletons were found at this site. Reisz actually prefers his batch of miscellaneous bones, however, saying, “When you get a beautiful little embryo inside an egg, it's gorgeous, . . . but it's only a glimpse, sort of like a frozen moment in the embryonic life of the animal. Here, because we have limb bones at various different stages of development, we can actually follow the embryonic life of the organism.”
“The nests were inundated by water and basically smothered, and the embryos inside the eggs died and then decayed,” Reisz speculates. “And then more water activity moved the bones and concentrated them into a very small area. We only excavated 1sq m of the ‘bone bed’ and we got more than 200 bones.”3
Among the bones recovered with the eggshells are 24 femur bones about as thick as pencil lead. The longest are twice as long as the smallest, suggesting that quite a bit of growth occurred in the egg. Cross sections show the vascular spaces were quite large, and in living embryos such large vascular spaces are associated with rapid growth. The capacious vasculature of these bones therefore suggests that these embryos grew remarkably fast. The incubation period is of course unknown, but Reisz believes they were “growing quite fast, faster than other dinosaurs and faster than a lot of living animals whose embryology we know very well.”3
The bones also showed the tell-tale marks of being shaped by muscles, they report, demonstrating that the developing animals moved while inside the eggs. Birds do this, they report. (So, not surprisingly, do modern reptiles. Turtle embryos can even move toward a heat source outside the egg.)4
Synchroton X-ray scanning suggests the fossils may also contain residual organic molecules, possibly collagen. “Organic remains [of dinosaurs] have been found before, but this is by far the oldest,” Reisz says. This finding—because of the vast age involved—is controversial among evolutionary paleontologists. Paleontologist Lius Chiapppe of the Natural History Museum of Los Angeles County, commenting on the report, says, “This lends support to the idea that that some of these organic molecules . . . may actually be preserved over millions of years.” But Smithsonian paleontologist Hans-Dieter Sues says, “Almost every example of such organic material is hotly disputed. You can never really totally rule out contamination.” More invasive testing has not yet been done.
More and more we read reports of preserved “soft tissue” in fossils thought to be millions of years old. Such biomolecules are quite fragile, so such reports were (and still are) viewed with skepticism by many paleontologists. Yet some researchers, such as Mary Schweitzer last fall, have shown convincing evidence that the soft tissue they have found is not contaminant but is authentic biomolecular footprints—not of modern bacterial contaminants—but of these ancient animals. The question remains: how ancient? Just how long a biomolecule such as a protein or DNA could be preserved sheltered in a fossil is unknown, but 200 million years does seem quite excessive.
If the presence of organic material in these embryos is confirmed, the finding will add to the roster of remarkably ancient biochemistry. And while no imaginable mechanism could explain such preservation for millions of years, residual biomolecules sheltered within fossils since being suddenly buried in the global Flood less than 4,500 years ago is a lot easier to swallow. The preservation of proteins such as collagen and keratin, structures such as blood cells, and even bits of DNA are consistent with the young age of the earth, but are unbelievable in a millions-of-years scenario.
Rapidly occurring “hard-wired evolutionary changes” said to offer game-changing insights for wildlife management.
Ecology Letters has just published the first study to clearly demonstrate, according to the authors, that environmental change can directly cause rapid “evolution” of animals. They say this is an “example of evolutionary rescue”5 in a population threatened with extinction. The authors believe the changes they observed in soil mites should help “predict species responses over ecological or evolutionary timescales”5 and fulfill the “need to bring evolutionary biology into population management”5 of fisheries and wildlife.
The animal studied is the Sancassania berlesei soil mite—a tiny invertebrate that lives in dirt. University of Leeds professor Tim Benton and his team raised populations of soil mites in glass tubes with limited resources. In some tubes they removed nearly half of the adults every week, and in some they culled nearly half of the juveniles. They monitored the effect of this “decimation” on the population. At first the mite populations decreased on a trajectory toward “extinction.” But then, within just fifteen generations, the demographics and reproductive behavior of the mites began to change. As a result of the selection pressure placed on the populations, the mites nearly doubled in the time to maturity. And upon reaching maturity, these slow-growing mites were unusually fertile.
“We saw significant evolutionary changes relatively quickly. The age of maturity of the mites in the tubes doubled over about 15 generations, because they were competing in a different way than they would in the wild,” lead author Tom Cameron explains. “Removing the adults caused them to remain as juveniles even longer because the genetics were responding to the high chance that they were going to die as soon as they matured. When they did eventually mature, they were so enormous they could lay all of their eggs very quickly.” Adding the evolutionary angle, Cameron says, “The genetic evolution that resulted in an investment in egg production at the expense of individual growth rates led to population growth, rescuing the populations from extinction. This is evolutionary rescue in action and suggests that rapid evolution can help populations respond to rapid environmental change.”
“This demonstrates that short-term ecological change and evolution are completely intertwined and cannot reasonably be considered separate,” Benton explains. “We found that populations evolve rapidly in response to environmental change and population management. This can have major consequences such as reducing harvesting yields or saving a population heading for extinction.”
Distinguishing this from ordinary population adjustments in response to environmental stressors, Benton says, “The traditional idea would be that if you put animals in a new environment they stay basically the same but the way they grow changes because of variables like the amount of food. However, our study proves that the evolutionary effect—the change in the underlying biology in response to the environment—can happen at the same time as the ecological response. Ecology and evolution are intertwined.”
Based on this sort of information, those who manage fisheries may be able, the authors believe, to make more informed decisions by understanding the impact of those decisions on fish populations, their environment, and even the characteristics of the fish themselves. North Sea cod have, over the past fifty years, begun maturing at half their previous size and become less fertile. Pointing out relevance of the “eco-evolutionary response”5 to analyzing the cod problem, Benton says, “The big debate has been over whether this is an evolutionary response to the way they are fished or whether this is, for instance, just the amount of food in the sea having a short-term ecological effect. Our study underlined that evolution can happen on a short timescale and even small 1 to 2 per cent evolutionary changes in the underlying biology caused by your harvesting strategy can have major consequences on population growth and yields. You can't just try to bring the environment back to what it was before and expect everything to return to normal.”
This nicely done controlled study demonstrates the potential that created kinds of animals have to vary and adapt, thus producing in a short time animals that are very different from their ancestors. Yet, obviously, all the variations result in organisms that are still soil mites. The variations observed here are simply options available within the soil mite population, as those individuals that mature more slowly and are more fertile were selected to survive and reproduce.
Nothing about these variations suggests that the mites have acquired the genetic information to become non-mites. And nothing in the field of evolutionary biology has ever demonstrated that such a new kind of organism could thus evolve. These mites, like all created animals, reproduced in the way the Bible says—“after their kinds.”
The use of the “E-word” among evolutionists is very slippery, implying that because observable variations can happen in “ecological time” more dramatic evolutionary transitions to new, more complex kinds of animals could happen over “evolutionary time.” While variations are observable, evolution of new kinds is not and would require entirely different (and non-existent) genetic mechanisms.
This study may contribute to a more scientific approach to fish and wildlife management, but it does nothing to lend credence to evolutionary dogma. Neither does it demonstrate any need for principles of “evolutionary biology,” as only the ordinary observable principles of biology and genetics affected the results.
Climate change in the news
The Daily Mail, Der Spiegel, the Telegraph, and the Economist have all reported in recent weeks that our collective goose is not cooking as precipitously as predicted. Headlines about the past decade’s significant shortfall of world surface warming have further fueled the fires of climate change controversy. The Daily Mail, for instance, titled its headline: “The Great Green Con no. 1: The hard proof that finally shows global warming forecasts that are costing you billions were WRONG all along.”6
Because many mainstream scientists and political entities are convinced that global warming is the result of man’s activities, the response to the presumed crisis has had major economic impact around the world. Restructuring of industry and mandated alterations to consumer goods to decrease the emission of greenhouse gases—the alleged culprits in manmade global warming scenarios—has cost consumers and governments a great deal of money. U.S. President Obama’s proposed 2014 budget alone proposes a 6% increase in spending to research climate change (up to $2.65 billion) in addition to money designated for regulatory functions.7
Those skeptical of the magnitude and significance of climate change hasten to point out that only eleven years before the United Nations’ Intergovernmental Panel on Climate Change (IPCC) was created to sound the alarm about global warming, policy makers and mainstream scientists of 1977 feared we were entering a new ice age, warning of food shortages and erratic weather related to global cooling. Now, a graph based on the IPCC’s computer modeling shows that the earth really isn’t warming up as predicted. Leeds University climate change professor Piers Forster notes, “Global surface temperatures have not risen in 15 years. They make the high estimates unlikely.”6 And David Whitehouse of the Global Warming Policy Foundation says, “This changes everything. Global warming should no longer be the main determinant of economic or energy policy.”6
Other experts say this plateau is just a brief respite in a catastrophic trend. They note that ten years is only a short time, much too short to declare a winner in the debate. Nevertheless, the contempt with which politically correct doomsayers have treated those who are skeptical about the severity and man-made origin of global warming does seem to justify some rejoicing as they hear mainstream experts like Oxford University geoscientist Myles Allen say the catastrophic estimates are “looking iffy.”6 Demonized atmospheric carbon dioxide may really not be the cause of all our woes.
The shortfall in degrees does give a little breathing room, perhaps for scientists on both sides of the controversy to acknowledge the enormous complexity of the questions—how much global warming should we expect, what will be its significance, and is it within man’s power to restrain?
Marc Morano of ClimateDepot.com, which opposes the conventional view, says, “In the peer-reviewed literature we're finding hundreds of factors influence global temperature, everything from ocean cycles to the tilt of the earth's axis to water vapor, methane, cloud feedback, volcanic dust, all of these factors are coming together. They're now realizing it wasn't the simple story we've been told of your SUV is creating a dangerously warm planet.”
Elgie Holstein of the Environmental Defense Fund, however, denies that the lull is a surprise and says, “This is a highly complex calculation to make in the first place. The short period of time, only 10 years in which the increasing temperature has leveled, really doesn't tell us very much other than the fact that temperatures may still be rising but just not as fast as they were before.”
Dr. Andrew Snelling, who holds a PhD in geology from the University of Sydney in Australia, notes that the debate over climate change is far from a settled issue. He says, “There is a lot of controversy, not over climate change itself, as everyone agrees climate changes, but over the cause of such changes, specifically whether man has contributed significantly to such changes. I am personally aware of several secular professional scientific societies whose memberships are very divided on this issue, and the continuing debate is heated.”
We are, according to Genesis 1, responsible to care for the earth God created. More research is clearly needed on this important subject. Unfortunately, some who contend that climate change is a man-made problem base their views on unverifiable ideas about the untestable past. Neither speculation about the past nor a shouting match dominated by politically correct views should dominate the ongoing investigation. Perhaps this “respite” in rising temperatures will serve as a reminder of the importance of keeping discussion open for all quarters.
Remember, if you see a news story that might merit some attention, let us know about it! (Note: if the story originates from the Associated Press, Fox News, MSNBC, the New York Times, or another major national media outlet, we will most likely have already heard about it.) And thanks to all of our readers who have submitted great news tips to us. If you didn’t catch last week’s News to Note, why not take a look at it now? See you next week!
Help keep these daily articles coming. Support AiG.
“Is creation a viable model of origins in today’s modern scientific era?” This DVD features Bill Nye and Ken Ham debating one of the biggest questions concerning the scientific community today.
Answers magazine is the Bible-affirming, creation-based magazine from Answers in Genesis. In it you will find fascinating content and stunning photographs that present creation and worldview articles along with relevant cultural topics. Each quarterly issue includes a detachable chart, a pullout children’s magazine, a unique animal highlight, excellent layman and semi-technical articles, plus bonus content. Why wait? Subscribe today and get a FREE DVD download!