Neanderthals, humans and interbreeding: old bones, new evidence | The BioLogos Forum


(system) #1

While I am in the midst of an ongoing series on Adam, Eve and population genetics, a recently published analysis of an archaic human genome is too rich to ignore until my current series ends – and indeed, this new evidence will be useful as that series continues. As such, we will take a brief hiatus and explore these new and exciting findings.

This new study shows that a modern human living in Europe between 42,000 and 37,000 years ago had a very recent Neanderthal ancestor, within six generations back. These results give us more information about how human and Neanderthal populations interacted over time and geographic space, provide a clear example of how present-day humans are not the only individuals we need to account for in determining the population size of our ancestral lineage, and close a loophole that one Christian apologetics organization hoped would explain away the evidence for interbreeding.

The question of human/Neanderthal interbreeding has been a topic of much discussion in evangelical circles since 2010, when the Neanderthal genome was first sequenced and compared to the human genome. That comparison revealed that some modern humans derive a portion of their genomes from Neanderthals: anyone not from sub-Saharan Africa has about 1-3% Neanderthal DNA. The fact that all those not from sub-Saharan Africa have this DNA indicates that the interbreeding that produced this signature occurred just as humans migrated out of Africa and before separating into groups that went on to populate Asia and Europe. Those humans migrating into Asia would later encounter, and interbreed with, the Denisovans, a group related to Neanderthals. As such, present-day Melanesian (subset of Pacific islander) peoples have Denisovan DNA in addition to Neanderthal DNA. Consistent with this model, those of us who remained behind in sub-Saharan Africa have neither Neanderthal nor Denisovan DNA. As I wrote back in 2011, the picture as we had it then was as follows:

Assembling all of this information reveals the following tale: the common ancestor of Neanderthals and Denisovans migrated from Africa to the Middle East between 500,000 and 300,000 years ago, leaving a population behind that would eventually become modern humans (at around 200,000 years ago). In the Middle East, the populations destined to become Neanderthals and Denisovans part ways, with their differences accumulating over the next several hundred thousand years to make them distinct species. When a population of modern humans leave Africa around 50,000 years ago, they encounter, and breed with, Neanderthals shortly after. This genetic exchange is small, since there are partial reproductive barriers in place, but a small fraction of Neanderthal DNA becomes established in this lineage. Groups from this population then part ways, with some migrating into Europe and others into Asia. This latter group then encounters the Denisovan hominids, interbreeds with them, and a fraction of Denisovan DNA takes hold as a result. This population goes on to colonize southeast Asia, Oceania and Australia, where we see this variation today in Melanesians. Modern humans thus have different evolutionary trajectories: Melanesians have both Neanderthals and Denisovans in their lineage, Europeans have Neanderthals, and Africans have neither.

Given the rapid technical improvements we are seeing in paleogenomics (the sequencing of DNA from ancient remains), it was really only a matter of time before new information would be added to this overall picture. Last week, such a study was published: it analyzed the DNA of a European, modern human (named Oase 1 for the location he was found) who lived between 42,000 and 37,000 years ago. The results of the analysis were both straightforward and intriguing: this individual had much more Neanderthal DNA than present-day humans do (6-9%), and a large fraction of his Neanderthal DNA is present in continuous blocks – in other words, in several locations in his genome, he has runs of Neanderthal DNA that are far, far longer than those seen in any present-day human. Taken together, these results indicate that not only did this individual have Neanderthal ancestry, but he had very recent Neanderthal ancestry, within the six generations preceding him. At the point of hybridization, his human/Neanderthal hybrid ancestor would have two chromosome sets: 23 from the human parent, and 23 from the Neanderthal parent, with one chromosome from each making up each pair. This hybrid individual would thus have runs of Neanderthal DNA as long as each chromosome. In the successive generations as this individual bred with a human, their offspring bred with a human, and so on, these long stretches of Neanderthal DNA would be broken into smaller and smaller stretches by recombination with human chromosomes. The fact that the subject of the study still has a several very long runs of Neanderthal DNA in his genome allows us to estimate, based on known human recombination rates for various locations in the genome, just how many generations exist between the subject of the study and his hybrid ancestor. The results indicate that not more than six generations separate them, or less than 200 years.

Scientifically, these results are significant because they are the first genetic evidence that humans and Neanderthals interbred in Europe, long after the initial interbreeding events that occurred in the Middle East shortly after humans left Africa. For Evangelicals interested in the evolutionary history of our species, these results are a “smoking gun” for human/Neanderthal interbreeding. Moreover, these results close a particular scientific loophole that one Old Earth Creationist (OEC) organization, Reasons to Believe (RTB) has promoted as an alternative interpretation of the Neanderthal/human interbreeding evidence. Let’s explore how this new evidence creates significant problems for RTB’s model.

Neanderthals and Reasons to Believe: new evidence, new problems

When the Neanderthal genome was first sequenced and analyzed in 2010, RTB came out strongly against the notion that humans and Neanderthals interbred, since this notion stands in sharp contrast to their stance that humans are separate creations that share ancestry with no other species. As such, RTB views Neanderthals as animals, and human/Neanderthal interbreeding as humans committing bestiality (for those following my current ongoing series, we will soon see that William Lane Craig holds a similar stance).

In 2012, RTB became aware of a minority scientific hypothesis – a proposal that the Neanderthal DNA seen in non sub-Saharan humans is the result of an ancient population structure in Africa prior to humans (or Neanderthals) leaving, not later interbreeding with Neanderthals in the Middle East. In this model there are at least two populations of hominins in Africa with limited genetic exchange between them, and Neanderthals and non-African humans emigrate from the same sub-population. In other words, the 1-3% Neanderthal DNA we see in non-Africans is because these two groups are, for a portion of their genomes, closer relatives to each other than either is to the population that gave rise to African humans. RTB has recently promoted the aspect of the model that suggested humans did not interbreed with Neanderthals as they left Africa, without discussing how the model requires some humans to share a more recent common ancestor with Neanderthals than with other human populations. While this minority hypothesis has not stood up to further experimental scrutiny, the point is now null and void for RTB in any case: we now have evidence that modern humans and Neanderthals interbred that cannot be explained by ancient African population structure. Neanderthal DNA is found in modern humans in only tiny segments,, due to 60,000 years of recombination breaking them into ever-smaller stretches. In the case of Oase 1, however, we have the DNA sequence of a human with large continuous swaths of Neanderthal DNA from a very recent hybridization event. Such large swaths of DNA could not have been transmitted for hundreds of thousands of years from an ancient African sub-population without recombination: they are recent, and indicate that humans interbred with Neanderthals within the last 42,000 years.

As our technological ability to recover and sequence DNA from ever more ancient and poorly preserved samples, the trajectory of the evidence is likely to provide increasing challenges to RTB’s model regarding Neanderthal/human interbreeding.


This is a companion discussion topic for the original entry at https://biologos.org/blog/neanderthals-humans-and-interbreeding-old-bones-new-evidence

(Dcscccc) #3

from creationist prespective, neanderthals was fully humans. and even most of the “homo” species as well .yep, there is some variation. like we see in cats and dogs (homo erectus for example have a big variation in is brain size, but it still was homo erectus)).


(Joel Duff) #4

Yes the YEC perspective is that all “homo” lineages are fully human and in fact are all descendants of Noah’s family and thus are to be found in living in the last 4000 years. In fact there are some YECs such as Todd Wood that would also include some of the Australopithecines in the fully human camp. However, there are no genetic models that would allow for this kind of variation to have occurred over such a short time frame. The variation in domesticated cats and dogs is miniscule compared to that found in most species much less between species of cats. Also, the geological context of many hominid fossils is extremely challenging to the young earth perspective. Most problematic to the YEC position is that the scripture don’t support their view of hyper evolution. Had all dog species originated from a common ancestor on Noah’s ark then people should have witnessed dogs and hundreds of thousands of other mammals becoming new species before their eyes. Scripture records dozens of descriptions of animals that clearly identify them as being the same in morphological and behavior as they are today. Ie. no fast past change was occurring to them and thus no evidence that “species” are just variation of a kind.


(Preston Garrison) #6

Someone should do a study comparing the attempts to retain the YEC perspective with the similar attempts of the Millerites (later Seventh day adventists) to account for the Great Disappointment (the failure of Miller’s prediction of the 2nd coming on a particular day.)


(Albert Leo) #7

Dennis, as a geneticist you have every reason to be excited over the amazing progress being made in untangling the past history of human ancestry. I am in a totally different scientific field (computer-aided drug design) but I anxiously await every new report from the molecular geneticists. But did you ever consider that this “ammunition” might be headed to a “battlefront” that is of little real consequence to evangelical Christians or the YEC and RTB folks?

We all would like to know the “God’s Truth” about human origins. But we are obviously not in agreement by what is meant by the word, Human. Apparently some would apply that label to whatever species has been classified as Homo; others would limit it back in time to the Neanderthals who had brains slightly larger than we do today; most would limit the label ‘human’ just to Homo sapiens, which can be specified rather exactly with today’s molecular genetics.

But for purposes of religion, where we wish to discuss the implications of a covenant with our Creator, is it sufficient to specify the Biology? Shouldn’t we instead specify the Behavior that stems from the biology? The anthropologists who have impressed me the most (Ian Tattersall, Jared Diamond, Simon Conway Morris, and even the ethologist, Richard Dawkins) all agree that a Great Leap Forward in the behavior of the Homo sapiens line (the Cro-Magnon culture) suddenly produced a people who regularly buried their dead with grave goods, made masterful paintings and sculpture, created music–in short, they behaved like us; we would have accepted them in our communities. For over 100,000 yrs. the preceding Homo sapiens did not. Was this then the first of God’s creatures that He invited to join him in continuing creation? The biological mechanism for such a transformation from Brain to Mind is still unknown, but a possibility that could be investigated further is the unusual epigenetic C-methylation that apparently takes place in the brain. (Dawkins is content at this point to call it ‘programming’.) I have a presentation on my web site that goes into this in more detail, including the Frechman we gets along with less than 10% of his brain, and how Anne Sullivan managed to ‘program’ Helen Keller’s brain so she could operate in human society.

What do you think, Dennis? Any possibilities, or just hogwash?
Al Leo


(Lou Jost) #8

We actually have 3000+ yr old mummies of Egyptian pets and local animals that clearly belong to today’s species. We also have beautiful ancient Egyptian paintings of birds that could have been taken straight from a modern field guide.


#9

I actually dealt with this discovery and its implications for our model on the June 24 (2015) edition of our Ex Libris podcast: http://rtbapologia.podbean.com/e/did-neanderthals-interbreed-with-humans-in-europe/


#10
  1. Fascinating! I read your words and those of the main post of this thread with great interest.

  2. @aleo, I’ve found myself hesitant in recent years to define the word “human” and risk misusing it in the light of the scriptures. So I’ve gotten in the habit of the clumsy but careful term of “Imago-Dei-endowed descendent of HAADAM”. (Yes, call me a pedant on this one. I just feel like I have to be very careful when communicating to students and others, especially when I want to distinguish between HAADAM’s descendents and the Nephilim, the “Sons of God”, Cain’s wife’s tribe, and others! Perhaps others have felt similarly.)


(Joel Duff) #11

Yep, and cave art that is likely much older that portrays breeds of horses. In the YEC model donkeys, zebras, all horse breeds, and hundreds of other forms of equines that are extinct today were represented by just a pair of horse-like things on the ark and then spectated after departing the ark. Of course there is no evidence of any kind for such recent evolution from Scritpure, other historical writings/art, paleontology or genetics. Interestingly, YECs are now accepting so much common ancestry even if they have no model for the “evolution” of species in their time frame while progressive creationists likely, though I have not been able to find reference to this specifically, maintain separate origins of zebras, horses and donkeys.


(Albert Leo) #12

Prof. Tertius:

I am in total agreement that, for religious discussions, humanity began when an advanced primate (almost surely Homo sapiens) had the mental capacity to realize he had been created, and consequently wanted to know what relationship he should have with his Creator. It takes no stretch of the imagination to suppose that the Creator/God, who oversaw the evolutionary progress from ‘the slime of the earth’ to a creature with a Mind that wished to seek Him out, would welcome the newly-minted human as ‘Imago-Dei.’ But if we are trying to build bridges to link religion and science into a common purpose, we need to provide some sort of criteria that archeologists can apply to their excavations of past cultures. What sort of artifacts would clearly indicate a crossing of the threshold between ‘Simply Evolved Creature’ to ‘Image Bearer’?

To date the area most intensely studied for the dates 40K -100K BP has been Europe and western Asia. Here the most obvious evidence of a dawn of religious feeling is the reverent burial of the dead with goods for an afterlife. Some of the cave art and sculpture (e.g. chimera of human/lion forms) may indicate belief in a spiritual realm as well as a material one. Studies of this time period in Asia and Australia have not yielded as clear cut evidence–partly because the conditions for preservations are not as common (caves that offer attractive living space over many generations), and partly because of lack of expeditions to look for evidence. The best evidence for early ‘Imago Dei’ humans in Australia is cave paintings of Spirits from their fabled Dreamtime.

It is likely that the creation story of Genesis 1-4 was passed down as oral tradition for as long as 45K years before being put to writing. According to the scenario I am proposing, the ‘transition’ from Brain to Mind, from Creature to Imago Dei, took place in the Mideast (perhaps in the caves on Mt. Carmel), and (co-incidentally?) this is the time when Nearderthal and Homo sapiens commingled, and, to a small extent, interbred. The belief in a literal Adam and Eve need not hinge on the fact they would then become a “genetic bottleneck” for all of us their descendants. There were, perhaps, a million Homo sapiens scattered over the globe who had only to be taught enough language by those already [transitioned’ to serve as mates for A&E’s children. (people of Nod)

Now it is up to the biologists and geneticists to find the biological/neurological mechanism that did program at least one Homo sapien brain to become mind. As Ian Tattersall put it (Masters of the Planet) “The changeover of Homo sapiens from a non symbolic, nonlinguistic species to a symbolic, linguistic one is the most mind-boggling cognitive transformation that has ever happened to any organism.” And further: “The only reason we have for believing that such a leap could ever have been made, is that it was made.” (emphasis his) To me,that sounds like reason enough to fund an NIH Grant! Are you listening, Dr. Collins?
Al Leo


(David Hume (nom de plume)) #13

This podcast is only available to those who donate to the “ministry” behind this “model.” A less convincing contribution to the discussion is hard for me to imagine.


#14

I have been hearing for some time before this “discovery” that neandertals were humans, according to creation.com. This study helps to verify that. It is also interesting to read a number of times in scripture, ie. Chronicles, Kings, and other places, something like… “in those days, giants lived in the land.” From this alone we would deduce some changes in human appearance.


(Jan De Boer) #15

I have posted four posts about the history of humanity during prehistory.
Contents: evolution is a very slow process, which implies that humans from 500K BP were almost as intelligent and sophisticated as we are, if not equal or more advanced. Humanity recently living in Stone Age and collecting stones on the Moon just a few millennia later is totally inconsistent with that. Explanation: there were Earth-crust-shifts and killing floods, which left only a few people alive and destroyed any sign of the previous civilizations. (Read Bryan Sykes, The Seven Daughters of Eve, about those few people.)

We are producing a CO2-footprint, advanced technique and space travel. Previous civilizations produced similar CO2-footprints and had millennia more time to produce more advanced technique and space travel. We are traveling around the world and mixing genes all over the world. Previous civilizations must have done the same during millennia.

Are babies able to think? I asked that many people. “No” said most, “their brains are not yet sufficiently developed.”. “I don’t know” said a few. And not a single person said “Yes” so far.
My memory goes back to the time that I was less than five months old. I remember that I refused to learn to talk and later I was told that I only started talking after my second birthday. Yet I remember also that I clearly understood everything that was said to me, without knowing the words. Most people are thinking in words, a small part is thinking in images. I am thinking in the language of my soul and I cannot express what that language is. But it is superior beyond limits to any other language on Earth. (I try to write a post “Why I became Christian” about it.)

I do hope that you can imagine that I have severe difficulties with Creationists, but also with many statements I read in the posts and the replies.
Some examples:
“oral tradition for as long as 45K years “. In 45K years humanity developed from a single family at 60ky BP to over a billion people just before starting an industrial revolution.

“I am in total agreement ….”. You might ask SETI to send a message into space “Look, we know that you are out there watching us. Lets talk.”.

What about the following: We made the transition from brain to mind on the moment that God gave us a soul.

Becoming linguistic is not an advantage. It is a disadvantage. Telepathy, talking from soul to soul is much faster and free of misunderstanding. Yes it does exist! I have observed and experienced repeatedly and I’m frustrated that I’m unable to start it.


(Albert Leo) #16

@Jan_de_Boer First I must admit that there is much in your post that I do not understand, but I will respond to what I think I do.

I agree with nothing in your first and second paragraphs. There is absolutely NO archeological evidence for a modern human culture prior to the Cro-Magnon, approximately 45K yrs ago. There may have been periods in the past (e.g. Jurassic) that CO2 in the atmosphere has been as high as it is today, but there was no civilization that produced it. Of course I cannot comment on your understanding as a five month old baby, but none of the babies in my extended family give any evidence of it (my grandkids are having grandkids). But each is a miracle, just the same!!

Of course I believe that the acquisition of language was the key that separates us from the rest of animal nature, and thus I cannot consider it a disadvantage. After 68 yrs. of marriage, my wife and I do seem to communicate telepathically at times. However, I don’t think it will replace vocal communication.

As for areas of agreement: Yes, I also have serious disagreement with Creationists. And yes, I do believe that the transition of human Brain to Mind was contemporaneous with the acquisition of Soul. And aren’t humans fortunate to be able to exchange ideas as we just have?
Al Leo


(Jan De Boer) #17

Hello Albert

Thank you for your reaction.
It is true that there is no archaeological evidence for modern human culture.
But there is DNA evidence produced by Prof. Bryan Sykes c.s. Research on mitochondrial DNA has shown that all humans are descending from a single woman who lived 150ky BP and from one of 33 woman who lived some 25 ky BP. Research in the X-chromosome has revealed that all males are descending from a single male who lived 60ky BP. The geographical origin of the 33 women were also found. Prof. Sykes gave the spots in Europe: Puy de Dôme, the Alps, the Pyrenees. All are around mountains and equal or similar to the spots I had selected as places where small groups of people could have survived the Flood that beached Noah on the Ararat.
Archaeological research has revealed that there have been magnetic pole shifts 150ky BP, 60ky BP and 15kyBP.
Climatologist have found that there were during this period three different Ice Ages, one in Europe from 150ky BP to 60ky BP, one in North America from 60kY BP to 15ky BP, and the present since 15 ky BP around the North Pole and the South Pole.
At this point the geologists are in my opinion overlooking some facts and unable to make a personal mind shift:
The magnetic field is formed inside the Earth below the crust. Now please, look at the Earth as a set of five flywheels. 1) the central solid core, 2) the mass between the central solid core and the crust, 3) the crust, 4) the water in the oceans, the seas and the lakes, 5) the atmosphere.
The total mass of the crust is only 0,3% of the total mass of the whole system. The mass of the water and the air are negligible in comparison with the crust.
My statement is that the flywheels 1) and 2) remained turning as usual. There is no explanation at all why the poles might shift. You might do a simple test with a loose bicycle wheel: hold the wheel vertically in front of you by holding both ends of the axis in your hands. Let the wheel turn but not fast. Now you have a turning flywheel in your hands. Keep the wheel in front of you, turn 90° to your right and experience how the wheel gets a will of its own. Be prepared to turn back left or to step back and drop the wheel if you can’t hold the wheel. If the magnetic poles really had shifted, then flywheel Earth would still be tumbling. So it was not the axis of the Earth that shifted but only the crust.
North America was situated some 3000 km more North than today and covered with a 5 km thick layer of ice at one side of the axis of our turning Earth.
On a bad day the centrifugal forces started to move the crust South. It was not the pole that shifted but the crust that shifted.
To understand that requires a personal mind shift that most people are not able to make.
The Earth is turning East with zero speed at the North Pole and 1,666 km/h at the equator. When a piece of North America that turned East at a speed of 300 km/h went to a spot where the Pacific Ocean turned East at a speed of 800 km/h, then that piece of North America was flooded by the Pacific Ocean at 500 km/h and because the Pacific Ocean is some 3 km deep, the flood was also 3 km high. And something similar happened all over the world, and that was the Flood that beached Noah on the Ararat.
The energy that caused the Flood was built up during 45ky and the Flood was survived by 33 survival groups. The previous floods at 60ky BP and 150ky BP were built up during 90ky and were each survived by only one survival group.
Look on Youtube to the images of the tsunami that hit Japan some 10 years ago, imagine that the speed became ten or more times higher and the hight 2 or more km, and then tell me what could have been left as archaeological evidence.
However, evolution implies that our ancestors from 500ky BP were about as intelligent and sophisticated as we are. And there is population growth, even under the worst conditions. Presume that it requires a whole millennium to double the population, then a small group of people increases to more than a million in some 20 millennia. People are inventive and will reinvent Stone Age, then agriculture, next better tools, etceteras. We did! Our ancestors were reduced to 33 small survival groups, in total no more than some 300 to 500 people. And no more than 15 millennia later there are 7 billion people on Earth and we travel in space.
Just think what the survivors of previous floods may have achieved in the 90 millennia they had available.
Personally I presume that they developed space travel, started to colonize other planets, and/or built habitats in space and survived there when their civilization on Earth was destroyed by a flood.
I also presume that their descendants were the sons of the gods, mentioned in the Bible.

Robert S. Coe is an American geophysicist whose primary research involves the application of paleomagnetism to a broad spectrum of problems. He found, in cooperation with Mr Camps from Montpelier University, a pole shift of more than 8,000 km which happened in less than some 3 weeks. It was a hot item then, but nobody was able to find an explanation why and how this shift had occurred.
But for me it was the missing link of proof for my theory about the history of humanity and Earth.
I tried to get contact with him, but I’m not known as a scientist and I had never made any scientific publication, so I presume that his secretary has treated my e-mail as spam.
You could do yourself, him and me a great favor by contacting him and ask his opinion about my posts on this subject.
The worst that can happen is that he proves that I’m wrong, which would have the positive result that an incorrect theory is proven to be wrong and dropped.
Greetings Jan


(system) #18

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