Neanderthals Are Us
The picture we have of “modern” Neanderthal developments that preceded the arrival of Anatomically Modern Humans (AMH) evolves further with better dating.
In their announcement of a recent study by João Zilhão et al., BBC evaluates the discovery of Neanderthal make-up as modern human behaviour that preceded the arrival of modern humans:
Until now it had been thought by many researchers that only modern humans wore make-up for decoration and ritual purposes.
There was a time in the Upper Palaeolithic period when Neanderthals and humans may have co-existed. But Professor Zilhao explained that the findings were dated at 10,000 years before this “contact.”
“To me, it’s the smoking gun that kills the argument once and for all,” he told BBC News.
“The association of these findings with Neanderthals is rock-solid and people have to draw the associations and bury this view of Neanderthals as half-wits.”
In the original paper of January 19, 2010, João Zilhão et al. conclude:
“The Iberian finds show that European Neandertals were no different from coeval Africans in this regard, countering genetic/cognitive explanations for the emergence of symbolism and strengthening demographic/social ones.”
In other words, in the course of human evolution something altered in the human being that can’t be defined by mere IQ, and that still is important to the way we behave differently from animals – and even from early humans. Both Neanderthal and Anotomically Modern Humans (AMH) crossed this evolutionary boundary.
Note the evolutionary changes that led to the use of make-up among early men involve aesthetics here, not the capacity or just a way to solve a problem in order to survive. Aesthetics, that stem from the Self and that imply self-reflection, an important “human” criteria. Foucault wrote about the Self as a source of aesthetics, albeit his focus was rather on quite less primitive stylistic technologies of the self:
“I am referring to what can be called the “arts of existence.” What I mean by the phrase are those intentional and voluntary actions by which men not only set themselves rules of conduct, but also seek to transform themselves in their singular being, and to make their life into an oeuvre that carries certain aesthetic values and meets certain stylistic criteria. These “arts of existence,” these “techniques of the self,” no doubt lost some of their importance and autonomy […] Still, I thought that the long history of these aesthetics of existence and these technologies of the self remained to be done, or resumed (UP, 10-11).”
Why African Homo Sapiens would have reached this same evolutionary level about the same time as Neanderthal, and how come the geographic transition to modern humans (that could have been a matter of domestication processes rather than genetic development) is congruent to this change?
In 2008, the Washington University in St. Louis already summarized the implications of a more precise dating of the late Neandertals and Modern Human contact in Southeastern Iberia, where the Protoaurignacian and the Aurignacian I remain unknown:
“The human fossils from the upper levels of the Sima de las Palomas are anatomically clearly Neanderthals, and they are now securely dated to 40,000 years ago. They therefore establish the late persistence of Neanderthals in this southwestern cul-de-sac of Europe. This reinforces the conclusion that the Neanderthals were not merely swept away by advancing modern humans. The behavioral differences between these human groups must have been more subtle than the Middle-to-Upper Paleolithic technological contrasts might imply.”
The intermediate position of the local Neanderthal was described thus in the paper referred to (Walker et al., coauthored by Zilhao and Trinkhaus):
“At the same time that the Palomas humans exhibit a suite of derived Neandertal features and archaic Homo configurations long since lost among early modern humans, their morphological variation indicates that they deviate from the expected Neandertal ranges of variation. This pattern may be result of genetic drift in relative isolation, directional change or, perhaps more likely, population contact to the north.”
In a new publication, Zilhao arrives at an extended interpretation of the transition. The time-lines are now defined such that Aurignacien (taken indicative to modern humans) started there only at 37,000 BP. The Neanderthal phenotype that exhibited the above mentioned suite of derived Neanderthal and archaic Homo configurations had already disappeared at the time of the anatomically mixed AMH specimen of Lagar Velho:
“With the last of the region’s Neandertals dating to five millennia before the child was borne, crossbreeding between immediate ancestors (e.g., parents or grandparents) drawn from distinct ‘‘modern’’ and ‘‘Neandertal’’ gene pools is empirically untenable. Therefore, those features must represent evolutionarily significant admixture at the time of contact.”
The Lagar Velho child thus attests Neanderthal admixtures that are considered reminiscent of much earlier contact, since by then the Neanderthal type had already disappeared.
However, the most recent publications of Zilhao don’t answer our curiosity that concern the human phenotype up north across the Pyrenees, that was responsible for the early art at the basal Aurignacian of Hohle Fels Cave in southwestern Germany. How did they look like?
A carving found in six fragments depicts a woman with a swollen belly, wide-set thighs and large, protruding breasts, that carbon dating suggested to be at least 35,000 years ago.
“It’s the oldest known piece of figurative sculpture in the world,” said Jill Cook, a curator of Paleolithic and Mesolithic material at the British Museum in London in the news. By the way, most likely the contemporaneous women looked quite different.
Another find of the same artistic magnitude, a flute, was found here as well. Conard, 2009:
“Although arguments have been made for Neanderthal musical traditions and the presence of musical instruments in Middle Palaeolithic assemblages, concrete evidence to support these claims is lacking. Here we report the discovery of bone and ivory flutes from the early Aurignacian period of southwestern Germany. These finds demonstrate the presence of a well-established musical tradition at the time when modern humans colonized Europe, more than 35,000 calendar years ago.”
It is assumed that these finds are to be associated to anatomically modern humans. Conard:
“It’s 100 percent certain that, by the time we get to 40,000 years ago in Swabia, we’re dealing with people just like you and me.”
However, this seems to be at odds to the investigation results of Finlayson and Carrion (2007):
“Overall, it is clear that diagnostic and well-dated AMH fossils are not found west of the Iron Gates of the Danube before 32 kya, implying a relatively recent entry into western Europe.”
This factual evidence of a late arrival date of anatomically modern humans would also leave the domestication of the dog rather in the hands of (pre-AMH) Neanderthal offspring. Remains of the first dog were found in the Goyet Cave in Belgium and was dated 31,700 BP.
The replacement of Neanderthal in western Europe is still an enigma and strictly spoken the first known figurative sculpture and musical instrument might as well have been manufactured by Neanderthal, or people that featured a similar suite of derived Neanderthal and archaic Homo configurations as their contemporary Neanderthal neighbours found in Palomas. Like the people that domesticated the first dog in Belgium and the chiuld of Lagar Velho, they could also be modern humans that featured evolutionary significant Neanderthal admixtures.
Or does all of this indicate continuity of a magnitude that hitherto remained unrecognized?
Let’s take a look again at the Neanderthal Genome project. Green:
“We tested more than 70 Neanderthal bone and tooth samples from different sites in Europe and western Asia for bio-molecular preservation by removing samples of a few milligrams for amino acid analysis. The vast majority of these samples had low overall contents of amino acids and/or high levels of amino acid racemization, a stereoisomeric structural change that affects amino acids in fossils, indicating that they are unlikely to contain retrievable endogenous DNA. However, some of the samples are better preserved in that they contain high levels of amino acids (more than 20,000 p.p.m.), low levels of racemization of amino acids such as aspartate that racemize rapidly, as well as amino acid compositions that suggest that the majority of the preserved protein stems from collagen.”
Next, Green investigated if the sampled mtDNA was Neanderthal-like or not, taking mtDNA that resembles modern mtDNA as contaminated “Assuming that the ratio of Neanderthal to contaminating modern human DNA is the same for mtDNA as it is for nuclear DNA“.
“Whereas only around 1% of the mtDNA present in three samples from France, Russia and Uzbekistan was Neanderthal-like, one sample from Croatia and one from Spain contained around 5% and 75% Neanderthal-like mtDNA, respectively. One bone (Vi-80) from Vindija Cave, Croatia, stood out in that 99% of the 63-base-pair mtDNA segments and 94% of the 119-base pair segments are of Neanderthal origin.”
Thus, having samples rejected when apparent Neanderthal mtDNA resembles modern human mtDNA, then of course the result will be that “all Neanderthals sequenced to date differ from all contemporary humans“. If mtDNA is accepted when different for 99%, then why amino acids having low levels of racemization shouldn’t be investigated too since this is what Green did. However, Wall and Kim suggested a new contamination criteria departing from the positive correlation of nuclear DNA, and took degraded DNA as indicative to the differences between Neanderthal and modern humans. The circular interpretation of the results should be obvious, and may even extend to the current measurements of Neanderthal mtDNA.
In my opinion the apparent lack of evidence for gross admixture in human DNA either indicates the extinction of the Neanderthal offspring, or otherwise – intriguingly -the full scale integration of Neanderthal DNA into the modern human gene-pool.
Assuming the extinction of Neanderthal offspring is not so hard to do, even though this would complicate the previous extinction scenarios that concerned a whole would-be species rather than a hybrid lineage. However thus, talking about circular thought, the assumption of extinction seems to derive from meeting the preposition rather than independent investigation. To say it can’t so it isn’t, rather than it could but it isn’t, invites to the kind of circular thought we should try to avoid.
Moreover, “extinction” is a way to deal with Neanderthal traits of archaic AMH that does not even occur to the writers of a new article about the child of Lagar Velho, Priscilla Bayle et al. (2010). This article reminds us about the evolutionary changes of modern humans since 40 kya, that involve characteristics that can also be found among Neanderthal.
Therefore, a simple Neandertal versus modern human dichotomy is inadequate to accommodate the morphostructural and developmental variation represented by Middle Paleolithic and earlier Upper Paleolithic populations. These data reinforce the complex nature of Neandertal-modern human similarities and differences, and document ongoing human evolution after the global establishment of modern human morphology.
It will be hard to sustain that Neanderthal were not involved as ancestors of the modern humans only because Neanderthal traits were simply lost in the course of evolution. Then, considering full scale integration instead as the only other possible option, how could it be? How could we even imagine the integration of Neanderthal DNA within the modern human species to this extend, in such a way that not any sign of significant hybridization can be discerned within the modern gene-pool?
Genes that for sure crossed the phenotype boundaries have already been identified, and a mixture between archaic Asiatic types (divergence time 2 million years) and African types for certain genes is already generally accepted. There is still discussion on how this mixture stabilized (eg. Diffusion wave hypothesis). An overview:
– Some genes have very deep, non-African branches: the RRM2P4 pseudogene has a MRCA of ~2 MYA in East Asia (Garrigan et al., 2005); PDHA1 locus is another ~2 mya example supporting multireginality
– Microcephalin entered the modern human genepool at 37 kya, since older type has MRCA at 1.7 mya
– Disequilibrium at locus Xp21.1 (MRCA 1.9 myr old) points to admixture
– Gutiérrez, Sánchez & Marín (2002) show ancient mtDNA is very sensitive to phylogenetic methods, diagenetic modifications have altered the sequences, and conclude that Neanderthal and modern mtDNA may overlap.
– FOXP2 in Neanderthal is a potential argument for being of the same species as modern humans, to the point of being identical.
Moreover, by examining the mutations in DNA near Alu insertions in two completely sequenced modern human genomes, Huff et al.(2010) could calculate a significant bottleneck at 1.2 million years ago. This is in agreement to the assumed split time of African Homo Sapiens and Neanderthal. The average age of human DNA is about one million years, and some genes are even estimated at two million years. From this perspective Neanderthal DNA should indeed be consistent to modern DNA.
The solution to this problem may be all but genetic. The flexibility of human phenotypes may rather suggest a good deal of non-genetic differences between Neanderthal and modern humans. Still other differences correlate with current typological differences, such as the “occipital bun” that has also been documented among Europeans.
As for now, there is no knowledge of genes that unequivocally account for robust “Neanderthal” morphological features, such as those that involve a lower and larger cranium, a larger browridge, a larger nose, larger shoulder joints, a larger and broader rib cage, larger elbow joints, broader hips, shorter forearms, larger hip joints, larger and thicker patellae, shorter and more flattened tibiae and larger ankle joints. All these features may stem fully or partially from epigenetic, environmental interaction.
There is no reason to assume the disappearance of once outspoken Neanderthal features would to be due to evolutionary developments that are essentially different from domestication-like processes. Anatomically Modern Humans only look different.
The Neanderthals are us.
- Bayle – Dental maturational sequence and dental tissue proportions in the early Upper Paleolithic child from Abrigo do Lagar Velho, Portugal (jan. 4, 2010), link
- Conard – A female figurine from the basal Aurignacian of Hohle Fels Cave in southwestern Germany, 2009, link
- Conard et al. – New flutes document the earliest musical tradition in southwestern Germany (2009), link
- Fillion – Foucault on History and the Self, Laval théologique et philosophique, vol. 54, n° 1, 1998, p. 143-162, link
- Finlayson and Carrión – Rapid ecological turnover and its impact on Neanderthal and other human populations (2007), link
- Green et al. – Analysis of one million base pairs of Neanderthal DNA (2006), link
- Huff et al. – Mobile elements reveal small population size in the ancient ancestors of Homo sapiens (2010), link
- Wall and Kim – Inconsistencies in Neanderthal Genomic DNA Sequences (2007), link
- Walker et al. – Late Neandertals in Southeastern Iberia: Sima de las Palomas del Cabezo Gordo, Murcia, Spain, dec. 2008, link
- Zilhão et al. – Symbolic use of marine shells and mineral pigments by Iberian Neandertals, PNAS vol. 107 no. 3 1023-1028 (jan. 19, 2010), link
- Zilhao et al. – Pego do Diabo (Loures, Portugal): Dating the Emergence of Anatomical Modernity in Westernmost Eurasia (jan. 27, 2010), link