Monday, December 5, 2011

A Face Only an “Altruistic Homo” Mother Could Love?


Inferior view, revealing the characteristic deformities of this craniosynostosis: The posterior part of
the cranium is twisted to the left with respect to the sagittal plane; the left glenoid cavity is more
anteriorly placed than the right one. Source and adapted text

Theory surrounding our ancestor’s capacity for love and affection are unclear. The exact nature of ancient companionship have yet to be concretely established, leaving theories surrounding child care unclear even still. Yet, the discovery of a juvenile skull displaying a condition known as craniosynostosis allows paleoanthropologists to consider the presence of physical and possible mental handicaps in our history, dated to be 530,000 years ago. What commentary does this provide on the parental and emotional capacities of our Homo ancestors?


Dating from the Middle Pleistocene period, the skull has been identified as an “immature specimen” aged approximately 5-8 years at death. Discovered in 1976, the specimen’s cranial deformities continue to be the focus of debates surrounding the limits of compassion that the species Homo could convey towards their young. Craniosynostosis is a congenital birth defect that affects the structure of the infant’s head. The defect causes the one or more sutures that run along the skullcap to fuse prematurely. This constricts the growth of the brain, causing contortion of the skull into a long and narrowed shape, motor impairment, aneurysms, and mental retardation if intracranial pressure is severe enough and left uncorrected.



What can we NOT infer from this discovery? We cannot infer the exact level of mental impairment that the child suffered from. Likewise, we cannot infer the exact cause of death. Craniosynotosis is associated with intracranial pressure, which can cause a laundry list of syndromes including but not limited to the aneurysm and mental retardation previously mentioned. Because of this, we can neither infer to what extent the child was treated similarly, or different, than Middle Pleistocene Homo individual.

Virtual endocast of the skull. Note the general bilateral asymmetry, the occipitomastoid bulging of the left side, the anteriorly placed left temporal lobe compared with the right, and the protruding left occipital pole. Source and adapted text


What we can infer is that the child did receive some form of care. Gracia, who is responsible for the uncovering of the skull stated that, "It is obvious that [this] hominin species did not act against abnormal/ill individuals during infancy." Generally speaking, it would be unlikely for even a modern child to survive without a constant source of food, care, or contact. Because of the cranial deformities present in the child’s skull it is unlikely that food gathering would have been a task undertaken by this individual. At the most basic level, a constant supply of food and/or care was provided for this individual which, in turn, allowed for survival.


What we could we infer? We could infer that there had been enough resources within the group, most likely made up of several individuals, to accrue enough excess resources (the remains were found within a group of 28 other skeletal remains, all of European Middle Pleistocene Neandertal lineage). These surplus resources could have been used to either support the disabled child, or to support the primary care giver who may have been required to devote more energy to parental care than to other tasks. What can be said concretely is that a characteristic of the genus Homo was bipedal. Depending on the severity of impairment, the child may have had limitations on its motor coordination, and therefore, in the ability to be motile. A medium to large group capable of accumulating excess resources or the ability to have an individual devote more energy towards the child may have been necessary to its survival past infancy.


Even though this is the earliest case recorded of craniosynotosis, there have been other examples of individuals displaying altruistic characteristics. In one of the more well-known is “Nandy” the skeletal remains of a man in an Iraq cave who displayed fracture on the left side of his face leaving him blind in one eye, an atrophied right arm as a result of several fractures and the absence of a lower right hand. These injuries most likely occurred during adolescence, and yet he was aged between 40 and 50 years old.


In an interview conducted by Wired.com’s section of Weird Science, Dr. Penny Spikins, who co-wrote The Pre-History of Compassion, comments on the possibility of a society displaying altruism at the Shanidar Cave site:


“We look in the archaeological record for evidence of individuals who were sick, and not able to care for themselves. We see that in early Homo, and by the time we get to Neanderthals, that kind of record becomes much more extensive. Take the “Old Man of Shanidar.” He had had degenerative deformities in the b

ase of his legs, would have had difficulty walking, and had a crushing injury to his cranium, so he was probably blind in his left eye. The bones show those injuries occurred when he was adolescent, and he lived to 40. He was probably looked after for 25 to 30 years, which implies that it wasn’t just one person looking after him, but several. Most of our Neanderthal skeletons show some evidence of having been looked after for their injuries. And in the age of Neanderth

als, you also start to see evidence of deliberate burials and funerary rites. That means a shared feeling.”


Withered right humerus compared to robust left humerus. Photo: Chip Clark
Smithsonian Institution.
Source and adapted text


The problem with these inferences in both case studies is that we have no way of judging the developmental merit, the evolutionary significance or if not acting against the child was considered “right” or “good”. In short, we have no sense of what was normal for the time period. The contribution of this publication, and with paleoanthropology in general, is that it allows for a personal narrative. Because of the sole discovery of such a skull displaying this congenial birth defect, altruism cannot (and should not) be attributed to an entire society’s’ practices, we are only privy to the individual’s, and his or her caretaker’s, story. Though, the same benefit also poses a problem. We cannot draw overarching conclusions from these pieces of evidence presented in the article and one’s similar to it.


Further skeletal remains showing similar physical deformities may be missing from the archaeological record because of mistreatment. They may have been abandoned as infants or even disallowed from being buried in cemeteries belonging to the society. Further evidence is needed to draw a definitive conclusion about the limits or capabilities of altruism, though these case studies provides an insight about the capabilities that our Homo ancestors could have, pertaining to compassion and resource allocation. If we had access to more examples of individuals surviving deformities, how could we look at altruism? Is the behavior a result of a higher categorization of morality, affection, empathy, or accident? Is it possible to distinguish the intangibility of emotion through the archaeological record?




Further reading:

The Neanderthal Skeletal Remains from Shanidar Cave, Iraq: A Summary of Findings to Date T. D. Stewart. Proceedings of the American Philosophical Society , Vol. 121, No. 2 (Apr. 29, 1977), pp. 121-165. http://www.jstor.org/stable/986524

Sources

The Prehistory of Compassion: Neanderthals Cared Too

Craniosynostosis in the Middle Pleistocene human Cranium 14 from the Sima de los Huesos, Atapuerca, Spain

Deformed skull of prehistoric child suggests that early humans cared for disabled children

The Sima de los Huesos crania (Sierra de Atapuerca, Spain). A comparative study

2 comments:

  1. Lovely post Kelsey - I really liked your careful assessment of what inferences can be made, and on what basis. Of course another whole question is whether Neanderthals and other archaic homos sapiens (and older species) even had emotions (such as altruism) that we would recognize and understand as anatomically modern humans. It's a fascinating area of study!

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  2. oh...and I love the title by the way!

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