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Gene surfing is a process in population expansion whereby certain variations become prominent and dominant in a short time, appearing to skip the slow, steady, uniform accumulation of variegation and diversification. According to a study of the population structure and genealogies of Saguenay Lac-Saint-Jean in Quebec, this type of drastic change accompanied the immigrant wave front that spread over the area in the 17th century. "Deep Human Genealogies Reveal a Selective Advantage to Be on an Expanding Wave Front" in Science magazine describes the resulting demographics.

Abstract
Since their origin, human populations have colonized the whole planet, but the demographic processes governing range expansions are mostly unknown. We analyzed the genealogy of more than one million individuals resulting from a range expansion in Quebec between 1686 and 1960 and reconstructed the spatial dynamics of the expansion. We find that a majority of the present Saguenay Lac-Saint-Jean population can be traced back to ancestors having lived directly on or close to the wave front. Ancestors located on the front contributed significantly more to the current gene pool than those from the range core, likely due to a 20% larger effective fertility of women on the wave front. This fitness component is heritable on the wave front and not in the core, implying that this life-history trait evolves during range expansions.

So gene surfing in an expanding colonization phase can produce a genetic revolution whose effects will be felt for hundreds or thousands of years downstream in history.

We wonder if the same wave front demographics might explain some of the following population phenomena:

• Large scale triumph of Norman male lineages following the conquest of England in 1066.
• Selective expansion of Middle Eastern genes in Tennessee (including Cherokee families, Jewish male and female lines and Melungeons)
• Relatedness among Jews and "Jewish diseases"
• Diversity-within-uniformity of Polynesians
• Population replacement of Old European (U, N) by Middle Eastern genes (T, J)  in Europe as a result of the Neolithic Agricultural Revolution

Many students of history are puzzled why old populations have the allele frequencies and heterozygosity clines they have. Genetic drift is only part of the answer. Gene surfing and selection in deep history are the rest of it.

A mental foramen is a small hole in the mandible whose purpose is to allow passage of nerves and vessels to the brain and probably also to relieve tension during chewing and gnawing. It has been identified as a sign of archaic humans, including Neanderthals. Do you have one?

I asked my dentist to look at my X rays on file and he confirmed I have a mental foramen. He has often told me I have "powerful" jaws. It is unclear whether there are normally two of them and what their typical positions are.

In a previous blog post, "Neanderthals in America," we discussed mental foramina (the plural of foramen), occipital bulges or bumps and other archaic skeletal traits. Melungeons seem to have many of these ancestral marks.

Do you? You might want to check with your dentist.

Studies show that Europeans have, on average, between 1 and 4 percent Neanderthal genes from an early out-of-Africa interbreeding period in the Middle East. Science has not decided to consider Neanderthals a separate species or sub-species in relation to H. sapiens sapiens (humans).

DNA Consultants offers an estimate of Neanderthal ancestry based on matches with other archaic humans called Neanderthal Index.

Line drawing of Neanderthal male ©DNA Consultants.

Yes, Virginia, there is a Neanderthal fossil record in America. And apparently a Neanderthal hybrid fossil record.

No genetics publication has put all the evidence together: the genetics establishment is still in denial about most things Neanderthal. The evidence is scattered and mostly unrecognized, but, in our opinion, conclusive and compulsive. Consider the following article:

Frank L'Engle Williams and Gail E. Krovitz, "Ontogenetic Migration of the Mental Foramen in Neanderthals and Modern Humans," Journal of Human Evolution 47/4 (Oct. 2004) 190-219. 

The mental foramen (literally "mind's little hole") is an anatomical trait very pronounced in Neanderthals, a small dimple in the lower jaw of the skull beneath the teeth, or mandible. It is found sporadically in humans, where it is classified as archaic. Among the places where it has been identified are the Oleniy Islands and Baltic region, Northwestern Russia in Cro-Magnon like Europoid and Mongoloid types, along with "large and massive" torus occipitalis or Anatolian bumps (Alexander Mongait, 1959; Marija Gimbutas, 1956); Bakhehisarai in the Crimea (Alexander Mongait, 1959); the Joman or Ainu of Japan (Carleton Stevens Coon, 1962); and the "race of giants" continually being unearthed in West Coast, Ohio Valley and New England archeological sites, caves and mounds.

Archaic giant skeletons with mental foramina, occipital bumps, double rows of teeth and other Neanderthal features are reported, in fact, all over the Americas. Fritz Zimmerman has gathered a lot of the evidence in a new book titled Nephilim Chronicles, of which a small excerpt was published in Ancient American magazine, issue 91, pp. 24-27. Here is one of the newspaper reports he cites:

Evening News (Ada, Oklahoma), November 8, 1912. PRIMITIVE MEN OF GIGANTIC STATURE.

Eleven skeletons of primitive men, with foreheads sloping directly back from the eyes and two rows of teeth in the front of the upper jaw, have been uncovered at Craigshill at Ellensburg, Washington. They were found about twenty feet below the surface, twenty feet back from the face of the slope, in a cement rock formation over which was a layer of shale. The rock was perfectly dry. The jawbones, which easily break, are so large that they will go around the face of a man today. The other bones are also much larger than those of the ordinary man. The femur is twenty inches long, indicating a man of eighty inches tall [6' 8"]. The teeth in front are worn almost down to the jawbones, due, it is believed, to eating uncooked foods and crushing substances with the teeth. The sloping skull shows an extreme low order of intelligence.

We note that the female mummy clutching a child known as The Thing on display at a roadside attraction on Interstate 10 north of Tombstone, Arizona, has a double row of teeth. It supposedly was one of three skeletons sold to the operator of the original site for $50 by a Chinese gentleman passing through. The Thing is discussed in several works by David Hatcher Childress. (My son and I paid our two bucks and saw it last Christmas on a road trip.)

Photo above:  Archaic skull from Oleniy Island studied by Marija Gimbutas among other archeologists, showing the position of the mental foramen, the result probably of Neanderthal interbreeding.

Photo below:  The Thing.

Did you know that Charles Darwin's On the Origin of Species, published in 1859, does not contain a single mention of the word "evolution"? I am reading it for the first time and was struck not only by the absence of that term in Darwin's first edition (it does begin to creep in after 20 years in later editions) but many other discrepancies between the historical Darwin and modern Darwinism.

For those inclined to believe conspiracy theories--for instance, that it was not Darwin, but Darwinists or even anti-Darwinists who invented the theory of evolution--here are some items to consider:

•  Darwin was a mediocre student at Cambridge, where he learned little science or mathematics and preferred theology. "He passed the final examination in January 1831 at an undistinguished position, tenth in the list of candidates who did not seek honours" (Richard Keynes, in the introduction to the first edition of Darwin's On the Origin of Species, published by the Folio Society, 2006).
• Darwin's disordered notebooks and papers, in which he supposedly developed the theory of evolution, only to keep it "secret" for 20 years, were not transcribed and published until 2000.
• The modern reconstruction of Darwin's theory of evolution evolved itself. It began to take iconic form only after the 1960s, when historians of science began to "read between the lines" of Darwin's work. His career was divided into an initial period of 10 years when he was a biologist on the Beagle, then a "secret period" of 20 years until he and Alfred Russel Wallace "simultaneously" broke the theory in 1858, and finally another 20 year period until "evolution" began to appear in his writings by name shortly before his death. 
• Darwin's interests were erratic, not to say eccentric. He spent eight years studying the sex life of a Peruvian barnacle. He published four extensive monographs on the subject between 1851 and 1854. During this period he wrote nothing on "transmutation of species," the early term for "evolution." His young son asked a playmate, "Where does your father do his barnacles?" (Keynes, xxi.)
• After barnacles, Darwin turned his attention to fancy show pigeons. He joined the Philoperisteronic Society and added an aviary to his house.
• The scientific establishment at the time did not exactly acclaim Darwin's On the Origin of Species. The geologist Adam Sedgwick wrote Darwin a scalding letter. "Many of your wide conclusions are based upon assumptions which can neither be proved nor disproved," Sedgwick said, accusing Darwin of "deserting the true method of induction." (xxiv). The astronomer Sir John Herschel called Darwin's work "the law of hiddeldy-pigglety."

Finally, no matter what you might decide about the "evolution of evolution," both Darwin and Darwinists reject the idea that Neanderthals might have been, in the words of the subtitle of On the Origin of Species, anything like a "Favoured Race." They died out, right?  This being so, it is interesting to me that a portrait of Charles Darwin (above) exhibits most if not all the characteristics of a Neanderthal:  sloping forehead, powerful jaws, craggy brow, occipital protuberance and large nose. We don't know quite what to make of it but wish Darwin had willed his skull as well as his thoughts to science.

In a review of Chris Stringer's book The Origin of Our Species (Lane, 2011), Jean-Jacques Hublin sides with one of the first promoters of the 30-year old Recent African Origin hypothesis and supports the notion that modern humans out of Africa entirely replaced Neanderthals because they were, well, fitter and superior.

See "Palaeoanthropology:  African Origins" in Nature 476, 395 (August 25, 2011).

But could the true scenario have been that "we" were already hybridized with Neanderthals, and that's why "we" won out? Recent work has brought evidence that Neanderthals gave "us" our immunities to a wide range of disease and thus allowed "us" to survive. The question doesn't have to be an either/or dilemma.

Above:  Krapina Neanderthal Museum. N. Solic.

Human origins: Shadows of early migrations

By Carlos D. Bustamante & Brenna M. Henn


Nature Volume: 468, Pages:1044–1045
Date published:(23 December 2010) DOI:doi:10.1038/4681044a
Published online22 December 2010

Analysis of ancient nuclear DNA, recovered from 40,000-year-old remains in the Denisova Cave, Siberia, hints at the multifaceted interaction of human populations following their migration out of Africa.

The new discipline of palaeogenetics is delivering increasing dividends, the latest news coming from Reich, Pääbo and colleagues on page 1053 of this issue. The authors' analysis of nuclear DNA of a human-like finger bone, found in Denisova Cave in southern Siberia, points towards a complex model of migration and colonization after anatomically modern humans moved out of Africa some 50,000–60,000 years ago.

Ever since 1925, when Raymond Dart's report of the first Australopithecus skull in southern Africa upended Victorian views of human origins, there has been debate over whether our species arose only once and spread throughout the world, replacing all extant species of Homo, or whether our ancestors interbred with the other populations and subspecies. The most extreme version of the 'candelabra' model of human origins — according to which human species arose multiple times independently of our Homo ergaster ancestors — has been largely discounted.

But it has been difficult to assess more nuanced models, such as the possibility of genetic exchange with some archaic populations, including Neanderthals, and now perhaps ancient Siberians. Until recently, genetic data and interpretation of the fossil record seemed to favour a complete-replacement model, in which all human species trace all of their genetic ancestry to a single origin in one or more African populations of moderate size some 200,000 years ago2, 3, 4, 5. However, the Denisovan nuclear genome sequence, along with that of Homo neanderthalensis published by some of the same authors6, suggest that the out-of-Africa population history of Homo sapiens is probably much more intertwined than previously thought, with more intertwining in some parts of the world than others.

Read more and follow discussion at Nature.

Triangles and circles respectively represent sampling locations of Neanderthal remains and of present-day human genomes. The blue arrows indicate generally accepted major migrations of anatomically modern humans, following their departure from Africa 50,000–60,000 years ago. At this time, there were two primary archaic species in Eurasia, Neanderthals and Homo erectus; Reich, Pääbo and co-workerssuggest that a third group was also present, represented by the ancient Denisovan genome. From ancient DNA, they identify additional putative events involving two episodes of limited gene flow: first, genetic admixture from Neanderthals to modern humans, shortly after the exit from Africa; second, subsequent admixture with the archaic population exemplified by the nuclear DNA extracted from the Denisova finger bone. This second event seems to affect only the ancestors of present-day Melanesians, who are thought to have colonized Papua New Guinea some 45,000 years ago. African populations, both past and present, are genetically highly diverse, as indicated by the multiple labels.

See also "New Hominin Probably Explains Distinctiveness of Melanesians"

Genetic history of an archaic hominin group from Denisova Cave in Siberia

By David Reich et al.

Nature 468: 1053-60.

Published online

22 December 2010

Abstract

Using DNA extracted from a finger bone found in Denisova Cave in southern Siberia, we have sequenced the genome of an archaic hominin to about 1.9-fold coverage. This individual is from a group that shares a common origin with Neanderthals. This population was not involved in the putative gene flow from Neanderthals into Eurasians; however, the data suggest that it contributed 4–6% of its genetic material to the genomes of present-day Melanesians. We designate this hominin population ‘Denisovans’ and suggest that it may have been widespread in Asia during the Late Pleistocene epoch. A tooth found in Denisova Cave carries a mitochondrial genome highly similar to that of the finger bone. This tooth shares no derived morphological features with Neanderthals or modern humans, further indicating that Denisovans have an evolutionary history distinct from Neanderthals and modern humans.

What Happens When 'Pressure of Natural Selection' Ceases?

Maybe I do not understand "classic Darwinism," but I am puzzled by the claims of numerous articles in leading scientific journals that evolutionary change in human beings is "accelerating." Since when? One such article was published several years ago by the National Academy of Sciences, "Recent Acceleration of Human Adaptive Evolution." It claims an acceleration in evolution in the last 1000 years, on an inferred and theoretical, not observed basis, needless to say. Its projections are based on the 4 million SNP database called HapMap, a collection of mostly European and American gene irregularities. Several books and a slew of articles in journals like Nature and Science have jumped on the scientific bandwagon. But we have a few embarrassing questions.

If the "classic" model of Darwinism was based on primitive man, New Guinea orchids and Galapagos turtles, wouldn't we need to redefine what selection and survival of the fittest and its other tenets really mean for, say, a Harvard or Stanford white male Ph.D. who sits in front of his computer most of the time or the current population of the United States, few of whom qualify as hunter-gatherers or tribal or starved or threatened by predators?

Isn't there rather a disconnect today between surviving and your genetic composition? Pretty much anyone can marry and have children with pretty much anyone they want to, and few people are dying off without issue from bad genes or fatal decisions.

If genes are supposed to mutate and produce more "fit" and eligible marriage partners because of "pressure" from the environment like drought or low-protein diets or too much or too little sunshine, how does evolution operate on a level playing field where the environment is a shopping mall or suburbia?

World population has increased from 200 million in the year 1 to nearly 7 billion. Perhaps the presumed rise in SNPs is an effect of population growth? Evolution was supposed to operate on the basis of selection, not indiscriminate proliferation.

Evolution, it is claimed, has now sublimated beyond the physical realm. It is internal, or mental, or spiritual, or cultural, or social, or political, or even (God help us) scientific. This was the super-clever dodge favored by Teilhard du Chardin, a Catholic missionary to China who wrote The Phenomenon of Man. He called it the noosphere. Whatever else, this latest Big Science Fair project requires a new definition. There are no measures possible beyond our present lifetime. We have no way of judging a Neanderthal's consciousness.

I'm sorry but I just don't get it. I wish someone would please explain it to me so I do not need to feel guilty about not reading all those pat-me-on-the-back and pip-pip-don't-you-know-old-man Victorian recidivist articles that I find, somehow, very self-serving.

I am an avid follower of the Darwin Awards but the only thing I can see accelerating are modern American and European scientists' delusions of grandeur.

NASA has embargoed until 11 a.m. Pacific Time tomorrow, Dec. 2, some big news that will be announced in a press conference in Washington. The title of the embargoed press release is "NASA to Hold News Conference on Astrobiology Discovery," and the scientific article supporting the news will appear in the journal Science. Some people have speculated the discovery concerns DNA in outer space.

The news conference will be will be broadcast live on NASA Television and streamed on the agency's website at http://www.nasa.gov.

The bombshell arrived with the May 7, 2010 issue of Science Magazine. Entitled "A Draft Sequence of the Neandertal Genome," it presented the years-long attempt of an international team of scientists to derive DNA from ancient female Neanderthal bones and determine if there was any genetic overlap with humans. The news was so sensational that the journal made the original scientific report and all collateral materials free to everyone, along with a podcast, multimedia presentation "The Neandertal Genome" and slew of links and forums for comments.

Read the original press release from the Max Planck Institute for Evolutionary Anthropology in Leipzig. It was embargoed for May 6, 2010, 8 p.m.

 

Svante Pääbo’s Neanderthal research group from left to right: Adrian Briggs, Hernán Burbano, Matthias Meyer, Anja Buchholz, Jesse Dabney, Kay Prüfer, Svante Pääbo, Janet Kelso, Tomislav Maričić, Qiaomei Fu, Udo Stenzel, Johannes Krause and Martin Kircher. (Copyright: Frank Vinken)

Some background

Discovered in a quarry in Germany in 1856, 40,000-year-old Neanderthal man became the first recognized early human fossil. The debate immediately began whether Neanderthals were a separate species or sub-species of Homo sapiens. German language orthographic reforms rendered the spelling of the name Neandertal in the twentieth century, although most people even today prefer to stick with the th of the original word. Neanderthals are named after the Neander Valley (German thal or tal) in which they first came to light.

More and more of them turned up over the years:  in Belgium (1886), a nearly complete skeleton in southern France (1908), Israel (then-Palestine, 1930) and Iraq (1953). The first ambitious genetic work was a partial sequencing of their mitochondrial DNA based on highly degraded specimens: Krings et al., Cell 90, 19 (1997). A second mitDNA sequence was achieved in 2000. The complete mtDNA sequence came in 2008:  Green et al., Cell 134, 416 (2008).

In the meantime, Neanderthals were found to have red hair and fair skin, body paint, customs, societies, rituals and art. They used fire, tools and weapons. They hunted bison, horses and other large animals and made bread of acorn meal. With their short arms and weak shoulder sockets, however, they probably could not throw spears. Before they were conquered by their smaller human cousins, they had colonized an area extending from Spain to Western Siberia and the Middle East. They were acclimated to northern Europe's icy temperatures and flourished especially before and during the last Ice Age. Then, suddenly, about 30,000 years ago, the fossil record goes silent. Their last holdout appears to have been in Spain.

Our picture of Neanderthals is likely to change radically now that we know they were among ancestors of ours, not a dead-end, primitive race. Some writers had already speculated, in fact, that Neanderthals were more advanced in many ways than their rivals, Cro-Magnon Man. Certainly, their religion was highly adumbrated. Some carried Venus figures on necklaces. According to the author of The Neanderthal's Necklace, Juan Luis Arsuaga (co-director of the World Heritage Site Sierra de Atapuerca in Spain), at one burial in Russia, a 60-year-old adult had 3,000 beads of drilled mammoth ivory sewn onto his clothes. A boy in the same burial wore a belt decorated with 250 arctic fox canines. There were also shells, armbands, head ornaments, bracelets, pendants, assegais, ceremonial staffs and other artifacts made of bone, antler, ivory and stone (p. 294).

The blockbuster draft of the Neanderthal genome just published noted genes linked to cognitive abilities, geo-spatial skills, language and motor coordination as well as strength, reproductive advantages and (what we knew already) cold adaptation. Much attention is likely to focus on the Neanderthal's signature occipital bun, noticed in isolated or vestigial populations like the Berbers, Saami, Canary Islands, Native Americans, Australian Aborigines and Melungeons. These populations probably preserved greater proportions of Neanderthal admixture than others.

Because the genetic legacy of Neanderthals (so far) has not been detected in the mitochondrial record, it is believed that gene flow came from males mating with human females. No male Neanderthal lines survive -- not surprisingly. Only autosomal DNA reveals the Neanderthal contribution to human populations.