human evolution  Encyclopædia Britannica Article

The evolution of Hominidae

Cro-Magnons

Cro-Magnon is the name of a rock shelter near Les Eyzies-de-Tayac, Dordogne, Fr., where several prehistoric skeletons were found in 1868. Sent to the site, the French geologist Louis Lartet began excavations in which he established the existence of five archaeological layers covered with ash. The age of the human remains found in the topmost layer—along with worked flint and the bones of animals of species now extinct—is Upper Paleolithic (c. 35,000–10,000 years ago), but the attribution of these to a clearly defined Upper Paleolithic culture is less definite. Traditionally regarded as Aurignacian, since typically Aurignacian artifacts were found in the rock shelter, they could be more recent, and it has been suggested that they should be assigned to the Perigordian (a separate industry covering approximately the same time period as the Aurignacian), which would give an age of about 25,000 BC.

Examination and analysis of fossils

Although it appears that at the time of discovery the remains of more than 10 individuals existed at Cro-Magnon, only fragments from some five individuals were preserved and studied, among them the cranium and mandible of a male about 50 years old. Considered representative of the Cro-Magnon type, this specimen is known as the “Old Man of Cro-Magnon.” Also preserved were skull fragments of about four other individuals, some bits of bone from a fetus or newborn child, and an assortment of bones attributed variously to the individuals mentioned above. The first subject mentioned, the Old Man of Cro-Magnon, has been regarded as typical of the Cro-Magnon peoples.

The skull is longheaded (dolichocephalic) and as seen from above has a pentagonal outline, with outward bulging of the parietal bones (at the sides of the skull). The forehead is straight, the browridges only slightly projecting, the cranial vault noticeably flattened, and the occipital bone (at the back of the head) projects backward. The cranial capacity is large, about 1,600 cubic centimetres (about 100 cubic inches). Although the skull is relatively long and narrow, the face appears quite short and wide. This combination is often regarded as a common feature of the Cro-Magnon race. The forward projection of the upper jaw (maxilla) is also distinctive. The eye sockets are low-set, wide, and rather square in shape; and the nasal aperture of the skull is narrow and strongly projecting. The mandible is robust, with massive ascending ramus (the upward projection of the lower jaw, where it attaches to the skull), strongly developed points of muscular attachment, and a quite prominent chin.

The root of only one molar tooth remains in the jaw of the Old Man of Cro-Magnon, a fact that contributed to the idea of his advanced age. In fact, it is probable that the loss of the majority of his teeth occurred after death. The teeth of the other individuals found at Cro-Magnon, which are similar to the teeth of other fossil humans classed as Cro-Magnon, show that the dentition of Cro-Magnons was nearly identical to that of modern humans. Most of the teeth recovered, however, especially the last molars, are distinctly larger than those of most modern peoples. Dental caries is sometimes apparent, and tooth wear is often extreme.

The remainder of the Cro-Magnon skeleton is not fully known from the remains found at the original site, which are incomplete and poorly preserved. Skeletal material attributed to the Cro-Magnon race from other sites, however, affords the general impression of robustness, probably combined with powerful musculature. The forearm is relatively long, as is the thigh; the femur (thighbone) has a very prominent linea aspera (a bony ridge that runs lengthwise down the back of the femur), and the tibia is flattened from back to front (platycnemy). The hand skeleton is large with short fingers, and the foot has a prominent heel.

Early investigators were impressed by the stature of Cro-Magnon man, as some reconstructions suggest that the Old Man of Cro-Magnon may have been as much as 190 centimetres (six feet three inches) tall. A restudy, however, suggests that the stature of the original Cro-Magnon remains varied from 166 to 171 centimetres (five feet five inches to five feet seven inches). The stature of several skeletons from the Grimaldi Caves (in Italy, near the French frontier), which show clear affinities to those of Cro-Magnon, was noticeably greater, with an average height of 177 centimetres. It is thus reasonable to conclude that, on the whole, the Cro-Magnon peoples were relatively tall.

Lesions noted in the Cro-Magnon skeletal remains have been attributed to wounds, but one analysis has suggested that these lesions are pathological in origin and may have resulted from the action of a toxic mushroom, Actinomyces israeli.

Two French prehistorians, A. de Quatrefages and Ernest Hamy, in 1882 took the Cro-Magnon fossils to be prototypes of a Cro-Magnon race. As opposed to the Neanderthal race—the first remains of which were found about 25 years earlier—the Cro-Magnons were then considered to be the most ancient form of Homo sapiens. To the Cro-Magnons were assigned other remains discovered before 1868 at La Madeleine and Bruniquel, in France; Engis, in Belgium; and Paviland, in Wales. Subsequently, further finds of human skeletal remains extended the geographic range of the Cro-Magnon peoples through much of Europe and into Asia and North Africa. Many of the central European fossils, however, belong to a type that differs from the Cro-Magnons called Brno-Predmosti, named for the area of central Czechoslovakia where they were discovered; like the Combe-Capelle remains, which they resemble, these individuals appear to have more primitive characteristics than typical for Cro-Magnons.

The place of Cro-Magnons in human evolution

The question of the relation of Cro-Magnons to the earliest forms of Homo sapiens is still unclear. It does appear, however, that Cro-Magnons (H. sapiens sapiens) and Neanderthals (H. sapiens neanderthalensis) are closer in affinity than was once believed. It long was thought that certain Cro-Magnon traits could be seen in human remains of Middle Pleistocene age (900,000–130,000 years old), but this argument no longer seems convincing. The tendency now is to locate the origin of the Cro-Magnon type in western Asia, as typified by the remains found at the Jebel Qafzeh and Skhul sites in Israel.

Perhaps as complex as the question of origin is that of the duration of Cro-Magnons. It appears that they flourished during the Upper Paleolithic, and that there was a tendency toward more gracile individuals, as seen in the fossils from Saint-Germain-la-Rivière in France. Individuals with at least some Cro-Magnon characteristics—called Cro-Magnoids—are found in the Upper Paleolithic, the Mesolithic (in Europe, c. 8000–c. 5000 BC)—for example, at Muge, Port.—and in the Neolithic (in Europe, roughly from 5000 to about 2000 BC); at the same time, remains have been found for individuals who were quite different, often brachycephalic (broad-headed). Some modern human groups that are more or less homogeneous are thought to have retained a close relationship to Cro-Magnon types, at least in their cranial morphology. Particularly noteworthy are the Dal people from Dalecarlia (now Dalarna, Swed.) and the Guanches of the Canary Islands, the latter of which is said to represent a relatively pure Cro-Magnon stock.

The culture of the Cro-Magnons

The ties between Homo sapiens sapiens, and particularly Cro-Magnon peoples and the various Upper Paleolithic cultures (e.g., Châtelperronian, Aurignacian, and Gravettian, which are classified on the basis of stone and bone tools), are relatively clear, although in 1979 Neanderthal fossils were found in Châtelperronian strata near Saint-Césaire, Fr. It is still difficult to establish precisely an outline of physical types and cultures for this period. Moreover, there are some detectable differences between populations and cultures of western Europe and roughly contemporaneous populations of central or eastern Europe.

Toolmaking

The Cro-Magnon peoples are generally associated with the Aurignacian culture tool industry, and perhaps with the Gravettian (also called Upper Perigordian). The Aurignacian tool industry is characterized by retouched blade tools, end scrapers and “nosed” scrapers, burins (chisellike tools), and fine bone tools, in particular long, flat points (spearheads) with cleft bases. Other bone and reindeer-horn implements are also seen: awls, tools for smoothing and scraping leather, and the so-called bâtons de commandement—bars of antler or bone with holes drilled in them, the use of which is still uncertain, although they may have been used for straightening arrow or spear shafts. The Gravettian industry differs from the Aurignacian industry in the use of an abrupt retouching technique to form what are called backed blades (i.e., tools with one edge blunted). Modern knowledge of all of these industries has been advanced as the ability to trace how and why various implements were used by Paleolithic peoples has improved.

Dwellings

The dwellings of Cro-Magnons were most often caves and shelters made by rock overhangs, but it is apparent that huts were made also; sometimes these were simply lean-tos against rock walls, but foundation stones and “pavements” of stone in the shape of houses are evidence of complete huts. These houses are not a new development with the Cro-Magnons, however; both the Neanderthals and earlier peoples of the Middle Pleistocene are associated with similar remains. It seems probable that the Cro-Magnons lived fairly settled lives. Studies of occupation sites and the types and extent of remains found in these sites suggest that the rock shelters were inhabited throughout the year rather than seasonally, and it is likely that these Paleolithic hunters moved their homes only when hunting or environmental conditions forced them to do so.

Hunting techniques

The climate in the habitable parts of Europe in Cro-Magnon times was cool to cold. Plants and animals of types associated with tundra and steppe environments were usual. Bone remains found at Cro-Magnon occupation sites indicate that they were successful hunters of such animals as reindeer, bison, wild horse, and even mammoth. As yet, very little is known of Cro-Magnon hunting methods—for example, whether hunting was individual or collective or if bows or traps were used. It is obvious from the animal remains, however, that hunting techniques must have been efficacious.

Aesthetics and religion

Although earlier human groups certainly had religious practices of some sort—the Neanderthal people buried their dead, a practice merely continued and elaborated by Cro-Magnon and later peoples—and no doubt had some appreciation of aesthetics as well, the first examples of prehistoric art are Cro-Magnon. Small engravings, reliefs, and sculptures of animals have been found in Aurignacian and Gravettian sites, as well as a few later statuettes of ivory or stone and occasional engravings in stone of female figures. These figures are usually large-breasted, wide-hipped, and most often apparently pregnant; they are generally assumed to be some sort of fertility symbol, perhaps used in religious or magical rituals intended to promote the fertility of the group or, possibly, of the game.

The Cro-Magnon people also appreciated the decorative aspects of art, as demonstrated by their use of animal pictures and (more often) simple geometric designs to ornament tools and weapons. It is believed that the people of the second half of the Upper Paleolithic—i.e., of the Solutrean and even more so the Magdalenian culture—were of the Cro-Magnoid variety and that they were responsible for the many splendid paintings of animals found in caves in France and Spain; but such sculptures as that called the “Lady,” or “Venus,” found at Brassempouy, Fr., are thought to be the work of Cro-Magnon artists.