Archive for June, 2008

Osteology and Dental Anthropology —- at the Portuguese

Monday, June 30th, 2008

This internship project will be directed by Cidália Duarte at the Instituto Português de Arqueologia, located in Belem, Lisbon, Portugal.  The internship will focus on the skeletal remains from the Final Neolithic-Chalcolithic dolmens (burial tombs) of Monte Abraão, Estria and Pedra dos Mouros that were excavated in the late 19th and later housed in the Geological Museum though never thoroughly studied. The information obtained from these studies will be used in the doctoral dissertation of Rui Boaventura who is studying the dolmens in the region of Lisbon.
 
 
  Students will be given more latitude and independent work loads in this internship program and are expected to be already familiar with the basic principals and methodologies of osteology and/or dental anthropology.  While other skeletal material will be reviewed and studied, the bulk of the
 
  
 
 
 collections to be considered are the dental remains. This internship will deal primarily with dental anthropology and morphology, the description and classification of teeth as well as the various pathologies that are evident in teeth.
 
 
 Students will begin by washing, cataloging and inventorying the various collections which are comprised of hundreds of teeth.  Within individual collections, or dolmen, students will be instructed how to properly study, classify and analyze the skeletal remains in order to answer such questions as the quantity of individuals in each tomb, their age and sex as well as any evident pathologies
 

Nonmetric traits of deciduous dentitions from bronze age Tell Leilan, Syria

Monday, June 30th, 2008

Dental nonmetric traits were scored on eighty-nine deciduous teeth that were recovered from the ancient Mesopotamian site of Tell Leilan (mid-third millennium BC) in northeastern Syria. Notable features of the dentition include a mild form of shoveling on the maxillary incisors, presence of Carabelli’s trait in 71% of maxillary second molars, and a rarity of accessory cusps on the mandibular second molars. Although based on a small sample, this study is intended as a contribution to the very limited amount of published data on deciduous dental morphology.

Variation in dental crown size within and between populations living on the Malaysian Peninsula

Monday, June 30th, 2008

This study, based on 518 sets of dental models of secondary school children and adults from Kelantan and Perak State, aimed to characterize normal odontometric variation within and between Malaysian populations. The sample included the four main ethnic groups living on the Malaysian Peninsula; Malays, Chinese, Indians and Jahai. Mesiodistal and buccolingual crown dimensions of all permanent teeth, except third molars, were measured to an accuracy of 0.01mm with automatic digital callipers. Tooth size was larger in males than females for more than 75% of the variables in Malays, Chinese and Indians. The magnitude of sexual dimorphism in buccolingual diameters tended to be greater than for mesiodistal diameters in all groups studied. Our findings confirm that there is considerable variation within and between Malaysian populations in permanent tooth size and this variability needs to be taken into consideration when undertaking anthropological and forensic investigations.

 

Genetic continuity of West and Nuclear Mesoamerican populations

Monday, June 30th, 2008

The Kircchoff’s model considers to the West of Mesoamérica like a marginalized region, recent works have contributed to contrast this hypothesis. Information of the dental morphology variation has been found on Mesoamerican populations. This article gathers the greatest number of populations of Pre-Hispanic Mexico. In the following work, samples are provided by eight West Mesoamerican groups and compared with other six samples listed in the bibliography for Nuclear Mesoamerica. For the bio-distance and clustering analysis, the Dental Anthropology System of the Arizona State University (DAS/ASU) has been used. The correlation between the geographical and genetic distance is illustrated in a genetic barriers map among populations. The results are discussed on the basis of history and dynamics of populations, taking into account other anthropological disciplines. In Early Periods there was few isolation between West and Nuclear Mesoamerican populations, and in Late Period there was no real genetic barrier or genetic discontinuity

A Pilot Study of the Mandibular Angle and Ramus in Indian Population

Monday, June 30th, 2008

The objective of this study is to evaluate the mandibular angle and to analyze the relationship of the angle to the gender; height and breadth of the ramus of the mandible so as to study its role in the anthropological diagnosis. The angles, height and breadth of the ramus of adult dry human mandibles of both the sexes were measured using a mandibulometer. The values obtained were analyzed statistically. The present study showed a statistically significant difference in the angle as well as height of the ramus of the mandible between both the sexes. The mean mandibular angle of Indian population when compared to that of European population was found to be lower by 9 degrees. The findings of this study might be useful in providing anthropological data that can also be used in dental and medical practice. However, the Indian mandible cannot be used for sexual dimorphism as is usual in anthropological work, whereas it appears to possess important unfavourable anatomic factors that may predispose the individuals to difficult laryngoscopy or intubation.

 

Mesio-distal of mandibular canine as a Sex and intercanine as the Age determinant

Monday, June 30th, 2008

Teeth are an excellent material in living and non-living populations for anthropological, genetic, odontologic and forensic investigations. To define the morphometric criteria for teeth in Haryana, the present study has been conducted in 102 patients (Male: 52, Female: 50) in the age group of 17-28 years. It was seen that statistically significant sexual dimorphism exist in the mandibular canine and intercanine distance weather measurements are taken on casts or intra-orally. It is concluded that whenever the mesio-distal diameter of mandibular canine is greater than 7.2 mm, the probability of sex being male is hundred percent. If the intercanine distance is greater than 25 mm, the age of male and female is more than 14 and 12 years in male and female respectively.

 

Tobacco and Areca nut Chewing induces Dental attrition and sensitivity

Monday, June 30th, 2008

Very little is known about the role of chewing of tobacco and areca nut on the oral dental hard tissues. An attempt was made to observe the effects of these materials on dental hard tissues. A total of 365 subjects (168 chewers and 197 non chewers) were enrolled randomly. The chewers were addicted to different chewing preparations. Examination of teeth was carried out clinically and dental attrition and staining were observed. The results indicated significantly higher frequency of dental attrition, sensitivity and staining of teeth among chewers than non-chewers. Further, analysis of data indicated a significantly higher attrition score for molar and anterior teeth among chewers with respect to non-chewers. The attrition score was also higher for premolar but this was not statistically significant with respect to non-chewers. The chewing these materials also leads to staining of teeth, which was also significantly higher among chewers.  Chewing areca nut and tobacco have the adverse effect on dentine structure and function as more dentine attrition and sensitivity was observed among chewers than non-chewers.

Sexual variation in bucco-lingual dimensions in Iranian dentition

Monday, June 30th, 2008

Sexual variation in the human skeleton and dentition is of great concern for both anthropologists and odontologists. Assessment of variation in dental size gives a clue about the behavior of a population, and also differences between the sexes. The purpose of this study was to analyze dental dimensions and sexual variation in Iranians and develop forensic techniques to identify human remains from the teeth when any other technique is not available or not reliable. The study is composed of 100 stone casts of Azad University dental students from Iranian population of either sex ranging age from 18 to 24 years. Bucco-lingual breadths from 14 teeth (I1 through M2 of the maxilla and mandible) are taken from the left side and analyzed using the discriminant function statistics. Results of the study revealed that males exceeded females significantly (P < 0:001) in dimensions. Stepwise discriminant function statistics suggested that upper M2 and lower C are the most contributory teeth to the function. In conclusion this research supports earlier studies that sexual dimorphism is population specific.

 

Canine Tooth Strength Provides Clues To Behavior Of Early Human Ancestors

Monday, June 30th, 2008

 

Measuring and testing the teeth of living primates could provide a window into the behavior of the earliest human ancestors, based on their fossilized remains. Research funded by the National Science Foundation and led by University of Arkansas anthropologist Michael Plavcan takes us one step closer to understanding the relationship between canine teeth, body size and the lives of primates.

In an article published in American Journal of Physical Anthropology, Plavcan and colleague Christopher B. Ruff of Johns Hopkins School of Medicine report on an initial examination of the function of the shape of canine teeth in primates. This is the first published comparative analysis of canine strength for primates.

Understanding more about the function of canine teeth can lead to new models for understanding human evolution. Plavcan has been studying primate teeth and skulls for 24 years and spent four years collecting dental data for this analysis.

The researchers compared the size, shape and strength of canine teeth from 144 primates with similar measurements taken from 45 carnivores. They examined the relationship of the size of primates’ canines to body size and the relative strength of the teeth. This comparison could help answer the speculation about the function of male primates’ canine teeth in the competition for females. Are the canines used as weapons or simply for display?

“The reason we wanted to use the carnivores is that we know carnivores use their canines for killing,” Plavcan said. “If primates’ canines are too weak to function as weapons, then they’re all just for show.”

Among anthropoid primates, it is well known that the canine teeth of males are up to four times as long as those of females. The researchers compared the canine teeth of male and female primates.

“If the male’s canines are stronger than the female’s canines that would imply there is sexual selection for strength and that the tooth is actually used as a weapon,” Plavcan said. “Female’s canines are short, and shorter, stubbier objects are harder to break. So, if the long, thin male canines are as strong or stronger than those of the female, that would also suggest they are capable of being used for fighting.”

The results were mixed in an interesting way.

“We found that the primate canines are generally as strong as or stronger than carnivore canines,” Plavcan said. “But they are not associated with any sort of estimate of sexual selection.”

Generally the canines of males and females were equally strong. Given that primates have such strong teeth in general, the researchers suggested a couple of possible explanations. It could be that all primate males have strong teeth because of a significant risk to reproductive success for any male who breaks a canine tooth. Or it could be that the strong teeth are due to basic inherited design.

Hominids – the primate family that produced humans – retain body mass sexual dimorphism; that is, males typically have a greater body mass size than females. At the same time, the difference in size in canine teeth between males and females is lost.

“This goes back to the earliest hominids,” Plavcan said. “In fact, one of the few diagnostic characteristics of hominid evolution is reduction in canine size dimorphism while maintaining strong body mass dimorphism.”

For example, gorillas have chunky teeth set in massive bodies. To have canines proportionately as long as other primates, a male gorilla’s canines would have to be 25 centimeters long, and the teeth at the base would then be too wide for his jaw.

“This suggests that there may be an upper limit on canine size in primates simply due to spatial constraints on fitting such teeth in the jaws,” the researchers wrote.

The difference in body size between male and female hominids has been the subject of study because it is an obvious and important trait. Yet there are drawbacks to using body size to understand sexual selection. A change in body size can impact many other aspects of life, including metabolism, feeding patterns and vulnerability to predators. Canine teeth, on the other hand, are a far simpler system.

“With canines, we can go in and effectively construct an experiment that allows us to control for all these other variables and look at only one thing,” Plavcan said. “The same phenomenon that works on the canines, we can translate into the body mass and then into behavioral models for the fossil record.”

Plavcan is an associate professor of anthropology in the J. William Fulbright College of Arts and Sciences at the University of Arkansas. He and Ruff are authors of “Canine Size, Shape, and Bending Strength in Primates and Carnivores” in the May issue of American Journal of Physical Anthropology.

 

Dental Anthropology & dental analyses helps determine age in chinese excavation

Thursday, June 19th, 2008

No crystal skulls, no alien corpses were found. But the archaeological excavations in Boljoon town, south of Cebu, offer just as interesting—and more realistic—finds on Cebuano culture and tradition.

chinese excavation siteNew discoveries have led to more questions, that need expert study, said Jose Eleazar “Jobers” Bersales, chairman of the Department of Sociology and Anthropology of the University of San Carlos.

Bersales reported the group’s findings in last Thursday’s lecture held at the Cebu Cathedral Museum that was also attended by Cebu Archbishop Ricardo Cardinal Vidal.

Bersales, an archeologist, said among those unearthed a few meters from the Patrocino de Maria Parish in Boljoon town south of Cebu province were 26 burials, antique ceramic dishes and jars, a necklace of precious stones and one large gold earring.

Even after three phases of excavations that began in February last year, they failed to find the original foundation of the centuries-old church. If found, it would help determine the actual date of the parish’s founding that had been debated by historians.

“Boljoon figures large in the defense against Islamic marauders,” he said on the significance of the parish in Cebuano history. The church was built in 1783 and was renovated during the time of paroko kapitan Julian Bermejo, one of only two priests given the title, Bersales said.

Archaeological finds

“We think this is a Christian burial site,” Bersales said. “Cebu was never Islamized.”

In a separate lecture on the skeletal remains, physical anthropologist and osteologist Bonn Vito Aure said the bones recovered on site were individually identified and sorted.

They determined the gender from the cranial (head) and pelvic forms. Age was determined through dental analysis of the wear and tear of the teeth.

Aure said there were two children—one aged three–three adolescents, seven young adults, seven middle adults and six old adults.

“Eighty percent of the individuals have caries (tooth decay), which indicates that they consumed a starch-rich diet. This means the people were already involved in agriculture,” he said.

Aure also noted the early use of toothpicks and the practice of tooth filing possibly for aesthetic purposes. But this needs further study since teeth filing in other Asian countries like Indonesia is functional to enable people to eat sago, a type of powdery starch.

Pre-Spanish Cebuanos in the town had osteomyelitis or bone infection which usually results from bacterial contamination, abscess or injury, based on the remains found.

Items 500 to 600 years old were dug up.

“This is the first time that gold was excavated,” the archeology professor noted. He cited one large tubular earring worn on the right ear of a male.

A similar sample, dated between the 14th and 16th century, is found in the Bangko Sentral ng Pilipinas Gold Collection.

There was also a necklace made from six carnelian gemstones, four red glass beads, six gold spacers and three gold pendants with carvings.

Other unearthed objects:

- Three ceramic dishes made during the time of Chinese Emperor Wan Li, the Zhangzhou period between 1573 and 1620

- two bowls from Anxi kiln in Fujian province in China produced between the 1590s and 1620s.

•A jar of the late Ming Dynasty (1590 and 1620)

Bersales said a similar artifact was recovered from the Dutch East Indies ship, Witte Leeuw, that sank in 1613 while on its way back to Holland.

•Five daggers and spears , some with fiber marks which could be abaca weave or sinamay.

In other excavation sites near the convent, experts unearthed bones of wild pigs and cows, piles of stones, small shells, broken pieces of ceramics and bronze Christian medallions.

Notable archeological facts

Males were also found buried with their hands clasped across their chests. The females were buried with their hands covering their genital area, said Bersales in a separate e-mail.

age of toothTwo distinct burial positions were noted. Some skeletons showed the head facing the south or oriented north-south. Another group was buried with the head oriented east-west.

The bones did not indicate that those buried were fisherfolk. They were likely traders.

“We have not found net sinkers or shells lining the grave that would be normally expected from burials found near the shore or beach,” Bersales said.

“This is the first time in the history of archeology in the Philippines where the head is covered with two ceramic wares since recorded excavations began in the 1920s,” he added.

Carbon dating of four bone samples sent to to the University of Arizona revealed that the skeletal remains are between 340 and 500 years old.

PUBLIC INTEREST

In a message to lecture participants, Cardinal Vidal said the interest in treasures unearthed in Boljoon is “not only the concern of the academe and the Church. It is everybody’s concern.”

Some of the archaeological finds are on display at the Cebu Cathedral Museum.

“Museums are a source of national pride and national consciousness and it is important for the children to see what it is like to be part of their country,” said Vidal, who opened the exhibit.

Vidal said experts had managed to discover “details of ordinary life” of the Cebuanos’ ancestors.

Other questions have to be resolved, said Bersales, who admitted it would take more than a decade of research at a cost of more than P1 million for archaeologists to fully assess the items discovered in Boljoon.

“Is the area a settlement or a burial site? It could be both, but we found one unit was topsy turvy,” he said.

Bersales also said they have to determine whether the items were from the colonial or pre-colonial period or both.

“When did Boljoon enter the orbit of permanent Augustinian work?” he asked.

“Excavations on the entire are of the church complex are needed, the publication of this book and video production to support the documentation of the findings,” he said.

Source: CEBU Daiily News