Medical anthropology and Ebola in Congo: cultural models and humanistic care.

Seldom have medical anthropologists been involved in efforts to control high mortality diseases such as Ebola hemorrhagic fever (EHF) This paper describes the results of two distinct but complementary interventions during the first phases of an outbreak in the Republic of Congo in 2003. The first approach emphasized understanding local peoples cultural models and political-economic explanations for the disease while the second approach focused on providing more humanitarian care of patients by identifying and incorporating local beliefs and practices into patient care and response efforts.

Interstitial cells of Cajal as precursors of gastrointestinal stromal tumors.

Interstitial cells of Cajal (ICC) are implicated in the regulation of gut peristalsis and are immunostained by antibodies against Kit (CD117), a tyrosine kinase receptor. Most gastrointestinal mesenchymal tumors (GIMTs) are of uncertain histogenesis, although many are CD34-positive. CD34 was found to colocalize with vimentin (Vim) and the Kit-positive networks of cells within and around neural plexi, indicating that ICC can be Vim- and CD34-positive. ICCs appear to be the only Kit+CD34+Vim+ cell in the gut. Formalin-fixed, paraffin-embedded tissues from 43 GIMTs were immunostained for Kit, CD34, Vim, PGP 9.5 (PGP, a neural marker), muscle-specific actin (MSA), and other markers including desmin (Des). Eight tumors were myoid (MSA+Des+Vim-Kit-CD34-), and one was a schwannoma (PGP+S100+Vim+Kit-CD34-), but 34 tumors were of uncertain histogenesis (gastrointestinal stromal tumors, GIST), exhibiting neither a complete myoid nor a schwannian immunophenotype. All 34 were Vim+, and 33/34 were either Kit (n = 30) or CD34 (n = 23) immunoreactive. Of these 34 GIST, 24 were negative for all myoid and neural markers, 6 were PGP+S100-, and 4 were MSA+Des-. The Kit+CD34+Vim+ immunophenotype of GIST suggests that they originate from, or have differentiated into, ICC-like cells; the term ICC tumor (ICCT) is suggested. Kit is a more sensitive marker than CD34 for ICCT, but both are required in tumor identification. All clinically malignant GISTs were pathologically malignant (size, mitoses) but also showed loss of either CD34 or Kit. "Blind" examination of electron micrographs in 10 tumors showed them to be heterogeneous. Some had features seen in normal ICC, but cells could not be positively identified as being adult ICC. GIMT may therefore be classifiable into those with pure myoid, schwannian (or neural) differentiation, but the majority are of ICC origin or show ICC differentiation immunophenotypically (ICCT).

Outcomes of unrelated cord blood transplants and allogeneic-related hematopoietic stem cell transplants in children with high-risk acute lymphocytic leukemia.

Acute lymphocytic leukemia (ALL) is a common indication for hematopoietic stem cell transplantation (HSCT) in children. Use of unrelated cord blood (UCB) has become increasingly popular as a stem cell source, given the rapid availability and decreased GVHD potential. Publications describing outcomes of children with leukemia who underwent UCB transplants have compared them to those having received unrelated donor marrow transplants. Results are similar. We compared our outcomes using UCB vs allogeneic-related hematopoietic stem cells in pediatric ALL patients since 1992. A total of 49 patients were analyzed. All patients were either in CR1 with high-risk features (n=21) or in CR2 (n=28) with initial remission less than 36 months. Patients received myeloablation with fractionated total body irradiation, cyclophosphamide, and etoposide and GVHD prophylaxis with cyclosporine and methotrexate. Antithymocyte globulin was added for UCB recipients to address the HLA differences. In all, 23 patients underwent allogeneic -related HSCT and 26 underwent UCB transplantation. Other than increased time to engraftment for UCB recipients, results are equivalent. The 3-year overall survival is 64% and 3-year event-free survival is 60% for both groups. Rates of GVHD and transplant-related mortality are also equivalent. UCB is a reasonable option for children with ALL who are referred for HSCT.

Electrical stimulation of the vagus nerve modulates the histamine content of mast cells in the rat jejunal mucosa.

Mast cells are best known for their participation in allergic reactions. However, a number of recent studies suggest that mast cells are subject to nervous control. In the gut mucosa, mast cells are intimately associated with nerves, and the psychologically conditioned release of RMCP II (a mucosal mast cell-derived mediator) has been reported. These data suggest the potential for CNS regulation of intestinal mucosal mast cells. In this study, we stimulated the cervical vagi and found an increased histamine content in mucosal mast cells, without apparent degranulation. Furthermore, these changes could be prevented by subdiaphragmatic vagotomy. These data support the potential for intestinal mucosal mast cell regulation by the central nervous system and suggest modulation of mast cells without degranulation.

Ivermectin distribution and the cultural context of forest onchocerciasis in South Province, Cameroon.

This investigation examined the cultural context of forest onchocerciasis in several communities in the Dja-Lobo Division of southern Cameroon. The study sought to elucidate behaviors that would enhance or diminish health status relative to forest onchocerciasis and other filarial infections, and to make culturally sensitive and appropriate recommendations regarding the development of health education materials and the long-term sustainability of the ivermectin distribution program in Dja-Lobo. The study consisted of two sequential components; the first was a qualitative study of a few severely affected villages and the second was a quantitative study of 212 randomly selected heads of households from eight villages. The Boulou and Baka peoples in these communities defined general filariasis (minak) as small worms under the skin, identified flies as important transmitters of the illness, and indicated that blindness and other skin and ocular problems were a consequence of the illness. Illness of the Dja (referring to an illness found near the Dja River) was another illness that was closely linked to onchocerciasis; local people indicated it was transmitted by the black flies found near the Dja River, resulting in severe itching and leopard skin. These and other cultural-behavioral data on filariasis were used to implement a health education and distribution program.

PIP: The cultural context of forest onchocerciasis was studied in the Boulou and Baka ethnic communities in the Dja-Lobo Division of southern Cameroon. A 2-day survey used focus group interviews followed by a questionnaire administered to 212 randomly selected individuals in 8 communities (88 male and 124 females heads of household) to assess their knowledge about onchocerciasis. Most people (98%) had some knowledge about the disease. Minak was the term used for filariasis by most people (97%) and people knew (90%) that black fly (nyamendimi) was responsible for its transmission. Other vectors of the illness identified were mosquitoes, dirty water, sorcery, and taboo foods. 81% thought that maternal transmission was possible and 66% indicated that filariasis could be transmitted sexually. Virtually all respondents associated itching and rash with minak (filariasis) and more than 60% also recognized the swelling of the skin and leopard skin as manifestations of filariasis. Filariasis, malaria, worms, and blindness were placed in the middle category when the severity of various diseases was ranked by 20 Boulou adults. In contrast, the Baka did not think that filariasis caused blindness, nor that it is linked to eye-worms. However, the 212 individuals ranked blindness as the most severe among other diseases (filaria, malaria, diarrhea, and intestinal worms). 80% of the Boulou and Baka adults had had filariasis in the previous year, but only 5% of the Boulou children and none of the Baka children had had filariasis during that time period. With respect to intestinal worms, 71% of the Boulou adults and 60% of the Baka adults had had intestinal worms in the previous year, while more than 90% of the Boulou children and all of the Baka children had had intestinal worms. Of the 90% who revealed that they had had filariasis at least once before, 69% sought treatment. 54% had tried traditional treatment, while 50% had tried Notezine, 49% had tried Phenergan, and 38% had tried M.G. Lumiere.

Community-based approach to schistosomiasis control.

With few exceptions, efforts to control schistosomiasis have relied upon ongoing community cooperation with "outsiders' rather than creating within the community the capacity and means for carrying out ongoing disease control measures with minimal external support. Offered as a useful model is a program in Kaele subdivision, Extreme North Province, Cameroon designed to establish and integrate within the primary health care (PHC) system the control of urinary schistosomiasis, hyperendemic in the region. At the community level, and with minimal dependence upon external resources, culturally appropriate and effective health education was instituted, the capacity to diagnose and treat schistosomiasis was created, diagnosis and drug therapy (praziquantel) was made available conveniently and at low cost, and, on a very limited basis, snails were controlled. Efforts were made to build upon and strengthen existing community structures and institutions rather than create new ones. The impact of the interventions was measured in terms of changes in knowledge and behavior, prevalence and intensity of infection, utilization of health services, and the ability to finance the control activities within the context of a generalized cost recovery system. Program successes and failures are discussed, as well as lessons learned and their implications.

Weaning and the nature of early childhood interactions among bofi foragers in central Africa.

Western scholarly literature suggests that (1) weaning is initiated by mothers; (2) weaning takes place within a few days once mothers decide to stop nursing; (3) mothers employ specific techniques to terminate nursing; (4) semi-solid foods (gruels and mashed foods) are essential when weaning; (5) weaning is traumatic for children (it leads to temper tantrums, aggression, etc.); (6) developmental stages in relationships with mothers and others can be demarcated by weaning; and (7) weaning is a process that involves mothers and children exclusively, with weaned children moving from close relationships with their mothers to strengthened relationships with other children. In many respects, these presumptions are consistent with contemporary Euroamerican practices: nursing stops early (usually before six months) relative to other cultures and takes place over a few days or weeks with the help of bottles and baby foods. Because bottles are available, weaning seldom appears traumatic, but it is seen as an important step in the establishment of independence between mothers and infants. By contrast, weaning from the bottle is often perceived as traumatic. Despite considerable academic and popular interest, weaning has seldom been studied systematically, especially in small-scale cultures. Qualitative and quantitative data from a study of Bofi foragers in Central Africa are used here to evaluate the cross-cultural applicability of the assumptions summarized above.

Culture and early infancy among central African foragers and farmers.

Everyday infant experiences among the Aka hunter-gatherers and the neighboring Ngandu farmers were observed and compared. Twenty Aka and 21 Ngandu 3- to 4-month-olds and 20 Aka and 20 Ngandu 9- to 10-month-olds were observed for 3 hr on each of 4 days so that all 12 daylight hr were covered. The Aka infants were more likely to be held, fed, and asleep or drowsy, whereas Ngandu infants were more likely to be alone and to fuss or cry, smile, vocalize, or play. The amount of crying, soothing, feeding, and sleeping declined over time in both groups. Distal social interaction increased over time among the Ngandu but not among the Aka. Despite striking cultural differences on many variables, however, functional context systematically affected the relative prominence of the infants' behavior in both cultural groups.

Accumulation of mast cells and macrophages in focal active gastritis of patients with Crohn's disease.

BACKGROUND/AIMS: Recent studies have shown that focal active gastritis seems to be the typical gastric pathology in Crohn's disease. The aim of this study was to compare the incidence of focal active gastritis, Helicobacter pylori infection and distribution of gastric mast cells and macrophages in patients with Crohn's disease, ulcerative colitis and H. pylori gastritis without inflammatory bowel disease. METHODOLOGY: Patients with histologically confirmed Crohn's disease (n = 25) or ulcerative colitis (n = 25) and control patients without inflammatory bowel disease (n = 25) were included in this study. Biopsy specimens were obtained from the antrum and corpus of each patient, and stained with hematoxylin and eosin and immunostained using antibodies to tryptase (AA1) and CD68. The number of mast cells and macrophages located in the lamina propria was determined. RESULTS: Focal active gastritis was detected in 54% of H. pylori-negative patients with Crohn's disease, but it was not found in patients with ulcerative colitis nor in the control group. The density of mast cells and macrophages in the lamina propria of H. pylori-positive patients was significantly higher than in H. pylori-negative patients in all groups. In the Crohn's disease group, the number of mast cells (antrum; 83 +/- 11, body; 89 +/- 11/mm2) and macrophages (antrum; 94 +/- 22, body; 92 +/- 17/mm2) in the lamina propria of H. pylori-negative patients with focal active gastritis was halfway between that in H. pylori-positive and H. pylori-negative patients. In focal active gastritis, mast cells accumulated at the border of focal active gastritis, whereas macrophages accumulated in the center of such lesions. CONCLUSIONS: Our findings indicated that the diagnosis of focal active gastritis, using immunostain for mast cells and macrophages, is the histological hallmark of gastric Crohn's disease. Macrophages might be associated with the formation of focal active gastritis in patients with Crohn's disease.

Demography and childcare in preindustrial societies.

PIP: The preliminary comparison of hunter gatherers, horticulturalists, and pastoralists is based on 57 preindustrial populations with demographic and child care data out of a potential of 1264 documented cultures from the Ethnographic Atlas. The purpose of this effort is to demonstrate that the demographic characteristics of a population influence its child care practices and provides clues to understanding child care patterns. Traditional practices and provides clues to understanding child care patterns. Traditional practices including multiple caregiving, multistage play groups, and parents or siblings as cultural transmitters are reviewed in a demographic context. Other emerging practices are also discussed: the role of stepparents and differential parental investment in sons and daughters. Anthropological data published and unpublished included only those using standardized methods on total fertility, infant or child mortality, and/or sex/age distribution. Problems with the data set include limited cultural representation, small study sizes, limited time trends, and reliability. There is a concentration on the ]Kung San, Efe, Aka, Gidjingali, Yanomamo, Dusan, Semai, and Kipsigis. Only 7 of the 57 are outside the tropics. Foragers are farmers are primarily represented, because the pastoralists are primarily East African and smaller samples. Tables provide cultural specific data on total fertility rates (TRF), infant and child mortality, and sex ratios at birth and among the juvenile and adult population. Sections are devoted to methods, general patterns, traditional characteristics of childcare based on 5 hypotheses, and emergent trends with 2 more hypotheses on stepparenting and male preference. 2 patterns prevail: 1) hunter gatherers and horticulturalists/pastoralists show great intercultural variability in fertility and mortality rates, and 2) the ranges and means of both groups are very similiar. In the discussion of specific cultures, the hypothesis is proposed and then examples are drawn from the 57 studies to provide support or rejection of the hypothesis. The 1st postulated that the level of multiple care increases with the number of adult women without children increasing. The 2nd hypothesis is that the greater the density or compactness of the settlement, the greater the level of multiple care. It is reasoned in the 3rd that fertility and mortality patterns influence the nature of indulgent care of infants. The 4th hypothesis is that sex and age distributions and compactness of the camp influence the nature of the play ground and type of supervision. The 5th is that father involvement will be greater in societies with low population densities or isolated. The 6th is that a child rarely stays with natural parents throughout the dependency period. The 7th is that male biased juvenile sex ratios will exist in societies where the cost of raising males is or = that of raising families, or where males contribute more calories to the diet, or where male mortality is high.^ieng

[Outbreak of Ebola hemorrhagic fever in the Republic of the Congo, 2003: a new strategy?]. / L'épidémie de fièvre hémorragique à virus Ebola en République du Congo, 2003: une nouvelle stratégie?

This article describes the last Ebola haemorrhagic fever (EHF) outbreak that occurred in the Cuvette Ouest Region of the Republic of Congo from January to April 2003. Epidemiological study demonstrated that the first patient, in whom diagnosis was made retrospectively, became ill on December 25, 2002. Subsequently until May 7, 2003, a total of 143 cases were recorded in the Mbomo and Kéllé health districts including 129 fatalities. Thirteen cases were laboratory confirmed and 130 were epidemiologically linked. Fifty-three percent of patients were male. Age ranged form 5 days to 80 years. Transmission involved direct contact with an infected person especially within families. Epidemiological data traced introduction of Ebola virus into the population to three primary cases mainly involving hunters. In all three cases development of the disease followed contact with non-human primates (gorillas) and other mammals (antelope) that had either been killed or found dead. Three health care workers were infected during the epidemic but nosocomial transmission played a minor role in the epidemic. On June 5, the Minister of Health and Population of the Congo Republic officially declared that the outbreak of EHF was over in the Cuvette Ouest Region. The last case was recorded on April 22 in the small village of Ndjoukou.

Anthropological contributions to a community-based schistosomiasis control project in northern Cameroun.

This paper describes how anthropological contributions and extensive cooperation between tropical medicine and medical anthropology researchers contributed to a successful community-based cost recovery schistosomiasis control project in northern Cameroun. The project led to increased knowledge about urinary schistosomiasis by local people, significant decreases in prevalence and intensity of the disease, and increased utilization of primary health care centers.

Exploration and mating range in African Pygmies.

The distributions of exploration range and of mating range were studied among Aka Pygmies of the Central African Republic. Exploration range is defined and methods of estimation for single individuals suggested. A simple exponential distribution is found for individual Aka Pygmies, with variation of exploration range (the parameter defining mobility) with sex, age and ethnic affiliation. Distribution of distances from birthplace and place of residence are compared and show modest differences. The frequency of visits to a given place has also been studied. The average distance between birthplaces of mates is very similar to the mean exploration range. Correlations between individual exploration and mating ranges suggest that it is the male who may be choosing a marriage partner among Pygmies. A theory by Boyce, Küchemann & Harrison (1967) on the relations between "neighbourhood knowledge" and mating distance is inapplicable because of its reliance on the Pareto distribution, which does not apply in the present case, and of other unnecessary assumptions, but the general principle of a close relationship between exploratory activity and mating distance seems valid, at least in the present case. Suggestions are made for causes for the difference between the present distributions and those with other shapes observed in less primitive economies.

Immunohistochemical evidence for estrogen receptors in meibomian glands.

PURPOSE: To look for sex hormone receptor distribution in three structures contributing to the normal human tear film: the conjunctiva, the accessory lacrimal glands, and the meibomian glands. DESIGN: An immunohistochemical study. TISSUES AND CONTROLS: Forty-one upper eyelid specimens were collected from 15 male and 26 female patients (age range, 1.5-85 years) during blepharoptosis surgery via posterior tarsoconjunctival mullerectomy (Fasanella-Servat or Gavaris). In addition, control sections of histologically normal breast, prostate, and skin tissue were obtained. METHODS: Immunohistochemical staining using mouse monoclonal antibodies against estrogen, progesterone, and androgen receptors was performed on all tissues and controls. Quantitation of the receptors was performed and expressed as percentage nuclear positivity. Specimens were divided into three groups based on the age of the patient: <12 years (n = 9); 18-55 years (n = 1); >55 years (n = 12). RESULTS: Forty-one specimens contained conjunctiva. All were negative for estrogen, progesterone, and androgen receptors. Twenty-four specimens contained accessory lacrimal glands of Wolfring. All were negative for the three receptors. Twenty-two specimens contained meibomian glands. All were positive for estrogen receptors; one was positive for progesterone receptors and one for androgen receptors. Using Minitab statistical software (Minitab Inc. State College, PA), analysis of variation revealed no statistical difference between sexes or between age groups studied. The sebaceous glands of skin were uniformly positive for androgen receptors. Sebaceous glands of the face and scalp (3 of the 15 skin samples) were also positive for estrogen receptors. CONCLUSIONS: Estrogen receptors are present in the meibomian glands of the upper eyelid. Unlike sebaceous glands elsewhere on the skin, the meibomian glands lack androgen receptors. Estrogen receptors may play a role in modulation of the lipid layer of the tear film, and their activity may be linked to meibomian gland dysfunction and dry eye syndrome.

Characterization of adrenergic receptors in the accessory lacrimal glands of the upper eyelid.

PURPOSE: To identify the histologic location as well as the exact subtype of adrenergic receptors in the accessory lacrimal glands of the upper eyelid. METHODS: Upper eyelid specimens were collected from 19 patients undergoing routine blepharoptosis correction via a posterior tarsoconjunctival mullerectomy. Immunohistochemical staining using polyclonal antibodies against human alpha 1, alpha 2, beta 1, and beta 2 receptors was performed on all specimens. RESULTS: beta 1 receptors were the predominant adrenergic receptor subtype in the glands of Wolfring. CONCLUSIONS: The presence of beta 1 receptors in the accessory lacrimal glands of the upper eyelid may suggest a possible role for selective beta 1 agonists in the treatment of keratitis sicca.

Insulin-like growth factors in pygmies. The role of puberty in determining final stature.

We measured the serum concentrations of insulin-like growth factors (IGF) I and II and testosterone in pygmy children, adolescents, and adults, as well as in controls, to determine more precisely the role of these factors in controlling growth. We had previously shown that growth hormone levels were normal in pygmies. Prepubertal pygmy children and controls did not differ in linear growth or in serum concentrations of IGF I and II. In pygmy adolescent boys, the mean (+/- SEM) serum concentration of IGF I was only one third that in control adolescents, who were similar to the pygmies in age and Tanner stage of development (154 +/- 22 vs. 435 +/- 37 ng per milliliter; P less than 0.01). A similar difference in IGF I concentration was observed in girls (278 +/- 18 vs. 570 +/- 25 ng per milliliter; P less than 0.01). IGF II and testosterone levels were normal in all groups. There was a significant difference in growth between controls and pygmies only during puberty. There was a marked acceleration of growth in the controls during adolescence, but such an acceleration was absent or blunted in the pygmies. These findings suggest that the short stature of adult pygmies is due primarily to a failure of growth to accelerate during puberty. We postulate that IGF I is the principal factor responsible for normal pubertal growth and that testosterone does not accelerate growth appreciably in the absence of an increase in the level of IGF I.

Intradermal transgenic expression of granulocyte-macrophage colony-stimulating factor induces neutrophilia, epidermal hyperplasia, Langerhans' cell/macrophage accumulation, and dermal fibrosis.

Granulocyte-macrophage colony-stimulating factor (GM-CSF), a pleiotropic cytokine, is up-regulated in a number of chronic skin inflammatory diseases, particularly atopic dermatitis. However, its role in these conditions remains largely unclear. To explore its function, we have established a rat intradermal transgene model by using a replication-deficient adenoviral vector expressing GM-CSF. Intradermal GM-CSF gene transfer led to a prolonged compartmentalized expression of transgene protein in the dermis. This expression induced an unexpectedly wide spectrum of pathologies in both epidermis and dermis, including neutrophilia, epidermal hyperplasia (acanthosis), an increased number of epidermal Langerhans' cells, accumulation of MHC II-positive macrophages, as well as mild eosinophilia in the dermis at earlier stages and upper dermal fibrosis at later stages. These findings thus identify GM-CSF as a potent multifunctional cytokine at skin site that is capable of evolving numerous inflammatory processes ranging from the early acute neutrophilia to later chronic fibrotic responses, and also suggest the important role of this cytokine in the development and perpetuation of pathologic changes in chronic skin inflammatory conditions including chronic atopic dermatitis. In addition, our study presents a novel model of adult normal animals that is useful for identifying and studying key cytokines involved in inflammatory skin diseases.

Measuring collagen fiber orientation: a two-dimensional quantitative macroscopic technique.

This paper describes the design, evaluation, and application of a new system for quantifying two-dimensional collagen fiber orientation in soft tissue. Series of transmitted polarized light images were collected using a custom-designed macroscope. Combined analysis of pixel brightness, and hue from images collected with a compensator plate, permitted the assignment of each pixel into the appropriate orientation band. Experiments were performed to quantify the linearity and noise of the system. Validation was performed on a specimen composed of strain-birefringent plastic strips at various orientations. Preliminary collagen fiber orientation data is presented from a tendon specimen. This study demonstrates the utility of this approach for studying collagen fiber orientation across large areas.

T cell-mediated exocrine pancreatic damage in major histocompatibility complex class II-deficient mice.

BACKGROUND & AIMS: Recent observations suggest a role for lymphocytes in human pancreatitis. However, existing animal models of pancreatitis are not immunologically based. In studies on major histocompatibility complex (MHC) II-deficient mice backcrossed five generations onto a C57BL/6 background, we discovered a progressive wasting disease due to pancreatic damage. The purpose of this study was to characterize this model of immune-based pancreatic injury. METHODS: The pathology was characterized histologically and functionally by assaying for pancreatic enzymes and glucose. RESULTS: By 6 months, a periductal lymphocytic infiltrate was observed that later developed into pancreatic lesions with extensive, but selective, destruction of acinar cells. Mice eventually lost weight, developed a hunched appearance, and began to pass large, pale pellets. Histology of affected mice revealed pancreatic atrophy with almost complete loss of acinar cells, although islets remained intact. Serum levels of amylase, lipase, and glucose confirmed the selective loss of the exocrine pancreas, with both amylase and lipase levels being significantly decreased in affected mice. However, glucose levels remained unaffected. Adoptive transfer of splenic mononuclear cells to athymic mice was found to transfer the disease. CONCLUSIONS: Aged MHC II-deficient mice develop an immune-based pancreatitis with selective loss of exocrine cells and function.

Cultural variation in Africa: role of mechanisms of transmission and adaptation.

Cultural inheritance can be considered as a mechanism of adaptation made possible by communication, which has reached its greatest development in humans and can allow long-term conservation or rapid change of culturally transmissible traits depending on circumstances and needs. Conservativeness/flexibility is largely modulated by mechanisms of sociocultural transmission. An analysis was carried out by testing the fit of three models to 47 cultural traits (classified in six groups) in 277 African societies. Model A (demic diffusion) is conservation over generations, as shown by correlations of cultural traits with language, used as a measure of historical connection. Model B (environmental adaptation) is measured by correlation to the natural environment. Model C (cultural diffusion) is the spread to neighbors by social contact in an epidemic-like fashion and was tested by measuring the tightness of geographic clustering of the traits. Most traits examined, in particular those affecting family structure and kinship, showed great conservation over generations, as shown by the fit of model A. They are most probably transmitted by family members. This is in agreement with the theoretical demonstration that cultural transmission in the family (vertical) is the most conservative one. Some traits show environmental effects, indicating the importance of adaptation to physical environment. Only a few of the 47 traits showed tight geographic clustering indicating that their spread to nearest neighbors follows model C, as is usually the case for transmission among unrelated people (called horizontal transmission).