Posts Tagged ‘Cro-Magnon’

Neanderthals

Friday, June 22nd, 2012

In this chapter the relationship between the Neanderthals and the generalized moderns of West Asia, i.e., the Cro-Magnons, is examined in more detail. From about 350,000 ya until about 24,500 ya Europe was occupied by Neanderthals, but about 46,000 ya their numbers began to dwindle and Caucasians appeared in their place. 

Figure 25-1


Contrary to the initial impression of Neanderthals as ignorant brutes, a better appreciation of their culture and accomplishments has humanized them. They made ornaments, bone tools (Zilhão, 2006a) and even a 43,000 to 82,000 year old flute (Fig. 25-1) from the bone of a cave bear1 Their brains were larger than ours (but not when body weight is taken into account), though the earliest modern humans were taller and more slender. They had full control of fire and the ability to flake stone to make the sophisticated weapons, e.g., front-weighted spears (Thieme, 1997), needed to kill big game, and the tools needed to butcher the carcasses to supply their heavily meat-based diets. Neanderthals took care of their injured and elders and “were the first people known to have buried their own dead,” 2 sometimes with artifacts, ochre (a red iron pigment), or flowers. (Arsuaga, 2001, pp. 272-275). Unlike erectus, who could not survive in the cold north, the modern behavior (and anatomical cold-adaptations) of the Neanderthals enabled them to survive there for hundreds of thousands of years. 3
The migration of the Cro-Magnons, the generalized Hss from West Asia, into Europe, discussed in the preceding chapter, began about 46,000 ya and continued in between the two ice ages, when forests replaced grasses, decimating herds of large herbivores (e.g., mammoth, horses, bison, and reindeer) and the Neanderthals sustained by them. The newcomers did not immediately replace the Neanderthals and Neanderthals managed to hang on until at least about 24,500 ya, 4 so the two very different populations of man occupied contiguous, and possibly overlapping, territories for at least 10,000 yrs. 5 How was it possible for them to co-exist in the same territory for such a long time?
One explanation is that they had different hunting strategies and therefore did not hunt the same prey at the same time, that the newcomers followed the herds, picking off the young, the old, and the ill, while the Neanderthals were ambush hunters, perhaps chasing large herbivores towards hidden hunters, who would suddenly raise massive spears, impaling the beasts. 6 Neanderthal spears, some with large and heavy stone points, would require thick, heavy wood, 7 but Neanderthals had strong bones and a heavily-muscled forearm 8 that gave them a powerful grip. (Balbirnie, 2005).
Another suggestion was made by Dr. W.W. Olson (by email), that Neanderthals may have been night hunters. Although most cold-adapted species, such as the East Asians, have smaller eyes that are less vulnerable to cold, Neanderthals, though they were well adapted to the cold, 9 had unusually large eyes. Also, one of the defining characteristics of Neanderthals is their occipital bun, the bulge at the back of their skull, where the brain processes visual information. (Figure 9-12). 

Figure 25-2


Although their bones were thick and dense, they often show signs of fractures that forensic anthropologists have described as similar to those suffered by rodeo cowboys who ride bulls and wrestle steers. (Fig. 25-2. 10
Europe was populated by many large herbivores, such as ibex, fallow deer, and mountain gazelle, some of which, e.g., aurochs (wild cattle, the bulls weighing over 2200 lbs), mammoth (16 feet at the shoulder, males over 12 tons), rhinoceros (11 feet long, two horns), and wild boar (~ 600 lbs, with tusks), were also very dangerous. Putting all these clues together, Neanderthal men may have surrounded and stealthily crept up on herds under cover of darkness, then threw or thrust their spears. The resulting pandemonium would have been a man-to-beast battle of considerable violence. 11
It must not have been easy for the more gracile Cro-Magnons to move into the territory of such a formidable adversary. But, although the Neanderthal males were larger and stronger than the Cro-Magnon males, the Cro-Magnon males had spears with lighter stone spear points that could be thrown farther and did not require being as close to prey. (Arsuaga, 2001, pp. 192-193; Shea, 2001). Also, because the Neanderthals’ legs were shorter and their bodies heavier, they used about 30% more energy in walking than we do, costing them more energy per mile and making it more difficult for them to keep up with migrating herds. 12 Due to different hunting strategies, the Neanderthals and the Cro-Magnons could live off the same food source while rarely fighting over it. 13 In addition to their greater mobility and superior technology, 14 the Cro-Magnons had dogs, which the Neanderthals did not have; dogs were a significant advantage in hunting. 

Figure 25-3


Another major advantage was better communications, cooperation, and social networks, and more trade, giving Cro-Magnons access to information and materials that could not be found locally. The larynx in the Neanderthals was higher in the throat, which would have limited the complexity of the sounds they could make (Arsuaga, 2001, p. 267) and their ability to communicate and exchange information, though they did have a hyoid bone, which is needed for speech. 15 The Cro-Magnons exhibited symbolic behavior, such as cave painting (Fig. 25-3) 16and making jewelry, which is associated with a show of status or group identity, but the Neanderthals did not. 17
Until the Cro-Magnons had acquired the technology to live in the same territory as the Neanderthals and compete with them, the Neanderthals had no Homo competitors but, once the Cro-Magnons had developed the sewn skins and constructed shelters with a fire inside that enabled them to live in the cold north, they were able to move into Neanderthal territory and hunt large mammals, the main stable of the Neanderthals diet, in addition to catching fish and trapping small mammals when large mammals were scarce. (Purucker, 1977, Chap. 7). Thus, the Neanderthals followed the usual path to extinction – anatomically specializing to better obtain a particular food source (large mammals), then dying out when that food source diminished (Chapter 4, Rule 3). The anatomical specializations of the Neanderthals served them well for hundreds of thousands of years, but after the climate changed and new competitors arrived, their specializations became a handicap. It took thousands of years, but eventually the generalized Cro-Magnons caused the extinction of the specialized Neanderthals.
Nevertheless, in a very real sense, Neanderthals did not go extinct, but live on today as part of those of us who are Caucasian. Caucasians can be grateful to the Neanderthals for giving us some of their genome, though the donation may not have been pleasant for the recipients.

Genes
Because Neanderthals and Cro-Magnons lived in the same territory for such a long a time, there surely must have been some interbreeding. We know that the Hss and Neanderthals were close enough genetically for any mating to result in fertile progeny; 18 they are, after all, both Hs. Yet when scientists analyzed mtDNA they had extracted from Neanderthal bones, they found no sign of Neanderthal alleles in the mtDNA of living Caucasians. 19 Similarly, no Y chromosome evidence of interbreeding has been found. (Krause, 2007b). 20Nevertheless, there is some other genetic evidence. 21 How is that possible?
It is a general principle of biology that the males of the more advanced and expanding population mate with the females of the less advanced and declining population (Sykes, 2001, p. 125), which suggests Cro-Magnon males mating with female Neanderthals, 22 something easily imaginable when Neanderthal women were hungry and Cro-Magnon males had some excess food or a confrontation occurred, leaving most of the weakened Neanderthal males dead. 23 The hybrid progeny would have had Neanderthal mtDNA but no Hss mtDNA and, if they had been raised by their mothers with the remaining Neanderthal population, no trace of Neanderthal mtDNA or nuclear DNA would have entered the generalized Hss population.
Those first hybrids would have had mixtures of various Neanderthal and Hss traits 24 and much more variety than either parent population. Only those hybrid individuals who had the best combination of traits for the European environment at that time would be naturally (and probably sexually) selected to pass on their alleles to the next generation. 25 For example, hybrid males who had both the generalized Hsscooperative and abstract-thinking mind and some of the Neanderthal strength and courage may have been more reproductively successful than the males in either of the parent populations. The same may have been true of female hybrids who had the gracile features of a Cro-Magnon female and (perhaps) the blond or red hair of a Neanderthal.
After a number of generations, the hybrids would become the more adapted population and would dominate both the Cro-Magnonsand the Neanderthals – the hybrids would expand and both the Cro-Magnon and Neanderthal populations would contract. Now the tables are turned, and it is the hybrid males who can take the Cro-Magnon and Neanderthal females. Will they take the few remaining heavy boned and primitive-looking Neanderthal women or the plentiful, delicate, and feminine-looking Cro-Magnon women? If they prefer the latter, theirprogeny, the Caucasians, would have Hss mtDNA and no Neanderthal mtDNA, but will nevertheless have some Neanderthal nuclear DNA.26 In that way the resulting populations, the Caucasians, could acquire some Neanderthal nuclear DNA without acquiring Neanderthal mtDNA.
Despite the failure to find Neanderthal mtDNA in Europeans, there is nevertheless some genetic evidence of interbreeding. Northern Neanderthals differ genetically from southern Neanderthals. (Rosas, 2006) and Europeans north of the Alps and the Pyrenees Mountains differ genetically from southern or Mediterranean Europeans. 27 Of course, the European genetic differences may be due to the selection of different traits in northern and southern climates, but another possibility is that European differences are the result of some Cro-Magnons in the north interbreeding with northern Neanderthals while other genetically-similar Cro-Magnons in the south interbred with genetically-different southern Neanderthals.
 A new study by a group of Icelandic scientists has found a 900,000 base pair inversion (i.e., the DNA string is backwards) in Chromosome 17 that is at least 3 myrs old. (Stefansson, 2005). The mutation is found in about 20% of the Caucasoids tested, is almost absent in Mongoloids, and is rare in Negroids; women who have the mutation have more children.
How did Caucasians get such an old mutation? Under OoA, it would have had to have come from Africans who supposedly evolved into Asians then into Caucasians, but very few of today’s Africans and Asians have it, so they must have lost it. But why would Asians have lost it when 20% of the Caucasians did not lose it, and the Asian and Caucasian environments are similar? A more likely explanation is that the inversion arose before the LCA of Neanderthals, Africans, Eurasians, and Caucasians in an Australopithecus that was in the Neanderthal lineage and the Cro-Magnons who migrated into Europe interbred with Neanderthals who had the mutation, giving it to their hybrid children, the Caucasians. Later, some Caucasians gave it to a few Africans and Asians.
Since the mutation was positively selected for (i.e., it was an advantage to have it), but only if the incidence of it in the population stayed below 20%, that suggests that the mutation becomes negatively selected (i.e., a disadvantage) when its incidence exceeds 20%. 28
There are a number of alleles found in Europeans that are not found, or at least are not common, in other races, including alleles that are involved in the development of the central nervous system. These alleles are so different from the main cluster of human alleles that they must have been picked up from archaic humans, such as Neanderthals. 29 An allele of the microcephalin gene appeared in Europeans about 37,000 ya, during the time that Cro-Magnons were moving into Neanderthal territory. This allele has an effect on brain size, and has been strongly positively selected in the Eurasian populations. But a haplotype with that allele is so different from the other variations of that haplotype that it must have diverged from them at least 1 mya. The explanation for this is that that allele first appeared in Neanderthals, not Hss. Then, about 37,000 ya a Neanderthal bred with an Hss, who picked up the old haplotype. 30

Traits
We do not know all the traits that the Neanderthals had, but we can surmise that if Caucasians have traits that are not found in any other people on the planet from whom Caucasians could have acquired them, then those traits either arose in the Caucasian lineage or were acquired from the Neanderthals. Although those traits include long faces (Coppens, 2004, p. 109), as well as a number of skeletal traits (Trinkaus, 2007), the most unique Caucasian traits are red hair, blond hair, blue eyes, and green eyes.
The origin of a trait is most likely to be where it occurs in the highest percentage (Chapter 4, Rule 11), and light hair and eyes (Figures 25-4) and the Neanderthal range (Figure 22-1) overlap well. 31

Figure 25-4a Figure 25-4b


The fact that blond hair and blue eyes are not found in Asians or Africans, despite some Caucasian interbreeding with them, suggests that those alleles are not ancient in Caucasians. 32 If those traits were ancient in Caucasians it is likely that they would have spread to enough Asians to be expressed occasionally, even though they are recessive, but that does not happen. On the other hand, the alleles would have had over 1.8 million years to arise in the Neanderthal lineage (before georgicus). Then there would have been at least 21,500 yrs (46,000 ya, when Cro-Magnons moved into Europe minus 24,500 ya when the Neanderthals went extinct) for the Cro-Magnons to acquire the alleles by interbreeding with the Neanderthals.
To further complicate matters, some desert Australian aborigines not only have blond hair and other Caucasian features (Figure 22-5Figure 27-4), 33 but at least one had blue eyes! 34 On the other hand, some aborigines have uniquely Neanderthal traits, such as the occipital bun and beetle-brows, which go back to georgicus (Figure 2-4).35 That may suggest that they got all the alleles responsible for those traits from the Neanderthal lineage, but some aborigines are not only more generalized than the Neanderthal lineage, they are more generalized than Caucasians. Chapter 4, Rule 3, that generalized goes to specialized, not the reverse, tells us that the Neanderthal lineage probably did not produce the Australian aborigine lineage, though they may have contributed to it. Instead, both lineages came from a generalizedAustralopithecus and the uniquely Neanderthal occipital bun and beetle-brows were acquired later by the Australian aborigine lineage, probably from an ancestor of the Neanderthals, such as georgicus or Heidi. 36 Because blond hair and blue eyes would not be an advantage in Australia, it is likely that these traits were carried there by early Caucasians.
Limited Cro-Magnon / Neanderthal interbreeding accounts for some of the traits that are common to Neanderthals and some Caucasians. 37 The Neanderthal occipital bun is also found among some early modern Europeans 38 and can still be seen today fairly often among Lapps, Finns, and people in southern Lancashire in the north of England (which had been invaded by the Vikings), the same people who are most likely to have blond hair and blue eyes.
If Dr. Olson is correct and the Neanderthal males did hunt wild cattle at night, an adventurous and highly risky behavior, it might also explain why Caucasians are more adventurous and take more risks than NE Asians, behavior that may be responsible for their greater number of discoveries and accomplishments, despite having slightly smaller brains and lower IQs than NE Asians. 39
The afrocentrists initially denied that the West Asians that became Caucasians had interbred with any archaic species of man as it was their position that modern Africans replaced all the archaic species of man without interbreeding. However, if Caucasians evolved from East Asians without interbreeding with Neanderthals, it is difficult to explain why the Caucasian skull is less neotenic than the East Asian skull since East Asian neoteny was beneficial to the East Asians, and the Caucasians lived in a similar environment. 

Figure 25-5


Figure 25-5 is a picture of a reconstructed Neanderthal child that is based on the skull of a Neanderthal child. The child in the picture looks hauntingly different, but she could easily pass for a European living today. 40 

Figure 25-6 Figure 25-7 Figure 25-8 Figure 25-9


An interesting feature possessed by some Neanderthals, some fossil Caucasian skulls (Coon, 1962, p. 504), and some living whites is a type of prognathism (“midfacial”). Compare the nose and jaws of the beautiful unnamed model (Fig. 25-6) with a profile of a reconstructed Neanderthal man (Fig. 25-7) and the Neanderthal child in Figure 25-5. The midfacial prognathism of Neanderthals can be seen in many Europeans and some Asians; even cartoons and comics of beautiful Caucasians often have midfacial prognathism, e.g., Blondie Bumsted.
Neanderthal prognathism is in contrast to the simian (“alveolar”) prognathism of many Australian aborigines (Figure 27-6), Africans (Figure II-1Figure 9-3Figure 9-4Figure 9-26Figure 10-11; & Fig. 25-8), 41 and apes (Figure 6-1 & Fig. 25-9, a baby bonobo). 42 In simian prognathism only the jaw protrudes, but in Neanderthal prognathism both the nose and the jaw protrude and, indeed, the nose protrudes even more than the jaw.
The Neanderthal and Caucasian nose is also longer and narrower than the African and ape nose, extending downward closer to the bottom of the upper incisors. (Figures 10-6 & 10-7; Howells, 1948, pp. 167-168). The profiles in Figure 25-10 illustrate the differences in prognathism. 

Figure 25-10


In the European profile, the jaw does not protrude, but the nose and chin do. In the Neanderthal (Hn) profile, the jaw and nose protrude, but there is very little chin. If the Neanderthal profile is crossed with the European profile, the result is a more attractive Hss/Hn hybrid profile that some Europeans have, with a protruding jaw, nose, and chin. In the simian profile, only the jaw protrudes and the nose is short, flat, and broad. Since Africans and most Asians do not have Neanderthal prognathism, 43 where did those Europeans who have it get it from, if not from Neanderthals?
The prominence of the nose, rather than the jaw, in Neanderthal prognathism suggests the use of weapons in fighting, rather than biting with teeth. Neanderthal prognathism is a combination of the partial loss of simian prognathism plus a cold-adaptive increase in the size and length of the nose to warm the cold northern air before it reached the lungs. (Some Caucasians also have large, unusually-shaped noses, e.g., comedian Jimmy Durante, psychic Pam Coronado.)
Interbreeding with Neanderthals offers a good explanation for how Caucasians obtained traits that are not particularly advantageous. It is called “selective sweep” or “genetic hitchhiking” and it works like this. Suppose the Neanderthals, who had lived in Europe for a long time, had only a single allele that was very advantageous for living there. (They probably had many, but let’s assume the simplest case.) And suppose that there was only very limited interbreeding between the Neanderthals and the newly-arrived Cro-Magnons. The limited interbreeding would transfer to some of the hybrid progeny not only the very advantageous allele, but also other nearby alleles that may not have been particularly advantageous at all, perhaps those for eye and hair color. The individuals who inherited the very advantageous allele were more reproductively successful than those who did not inherit it so, eventually, most of the expanding hybrid population had it. But those other nearby alleles that came along for the ride also spread with the advantageous allele. So, even though the other alleles were not particularly advantageous, most of the hybrids ended up with them as well. Neat, isn’t it? (Schaffner, 2006).
Thus, the hybrid Caucasians have a mixture of Cro-Magnon and Neanderthal traits, 44 but the absence of Neanderthal mtDNA in Caucasians suggests a much greater contribution to the Caucasian genome from the Cro-Magnons than from Neanderthals. 

Table 25-1
H-O Normal
Neanderthal 53 47
Australopithecus 0 100
African Eves 0 100
Skhūl/Qafzeh (Hn-Cauc. Hybrid) 0 100
Early U. Paleolithic
(> 120 kya)
18 82
Late U. Paleolithic
(300 – 30 kya)
7 93
Mesolithic (< 10 kya) 2 98
Medieval Europeans (1500 – 400 BP) 1 99


Figure 25-11


Fossil Evidence of Interbreeding
The best fossil evidence for Neanderthal interbreeding 45 is the presence of a different shape of a hole in the jaw that a nerve goes through to the teeth, known as the “mandibular foramen” (“jaw hole”). This hole comes in two shapes (Fig. 25-11), “normal,” which almost all living humans have, and “horizontal-oval” (H-O), which is almost entirely limited to Neanderthals and fossils of Europeans (Lewin, 1998, p. 404). Since the shape of the hole has no functional significance and the H-O shape is very unlikely to have arisen independently by chance in both the Neanderthals and the Europeans, the Europeans must have gotten it from the Neanderthals. Table 25-1 shows some of the frequencies of the H-O foramen (Wolpoff, 1997Frayer, 1992, p. 31). Table 25-1 shows that the H-O foramen was absent in Australopithecus, early Africans, and one hybrid, was most frequent in Neanderthals, and decreased in frequency in Europeans from ancient times to the present.
Figure 25-12 is a male skull, about 90,000 yrs old, found at Mt. Carmel in Israel. The Mt. Carmel skull shows features of both Neanderthals and Caucasians and is thought to be a hybrid or intermediate. 46 That is, if Caucasians are hybrids of Cro-Magnons and Neanderthals, then Mt. Carmel is a hybrid that had more Neanderthal (Figures 2-6 & 2-7) in it than Cro-Magnon (Figure 2-8). The skull capacity is 1518 cc, larger than the average of Caucasians (1441 cc), NE Asians (1491cc), and Neanderthals (1450 cc), but smaller than Cro-Magnons (~1570). 

Figure 25-12


In 1999, a 24,500 year old skeleton of a 4 year old boy (the “Lagar Velho” child), that was clearly a hybrid between a Neanderthal and a Cro-Magnon, was found in a cave in Lapedo Valley, north of Lisbon, Portugal. (Duarte, 1999). This skeleton shows that Neanderthals and early modern humans intermixed and produced children. The child was buried with a pierced shell and red ochre, which indicates ritual burial, a modern behavior.
Figures 25-13 and 25-14 are two more examples of re-constructed adult Neanderthals. 47 

    Figure 25-13            Figure 25-14


As with the baby-adult chimpanzee comparison (Figure 6-1), the adult Neanderthal is less neotenic than the child (Fig. 25-5). The brow ridges are heavier and the forehead slopes more than in most Caucasians, but even today they could “pass” as Caucasians.
In addition to fossil bones, artifacts have been found that suggest trading between Neanderthals and (West) Asians, and possibly even more intimate contact. Personal ornaments found with older Neanderthal fossils are similar to those found with fossils of Cro-Magnons, though previously the two populations were completely unassociated. (Zilhão, 2006b).
In the end, there are just too many traits and unusual alleles in Europeans for them to have all come from mutations. Moreover, some of the alleles and traits offer no obvious advantage, so it is hard to see how they could become so common in Europeans just from mutations.

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