The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.
The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check for the status of the paper. Users should always cite the published version of record.
American journal of physical anthropology, Jan 18, 2015
Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic d... more Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic defects has been reported in chimpanzee canines from the Fongoli site, Senegal (Skinner and Pruetz: Am J Phys Anthropol 149 (2012) 468-482). Based on an observation in a localized enamel fracture surface of a canine of a chimpanzee from the Taï Forest (Ivory Coast), these authors inferred that a nonemergence of striae of Retzius could be the cause for the "missing perikymata" phenomenon in the Fongoli chimpanzees. To check this inference, we analyzed the structure of outer enamel in three chimpanzee canines. The teeth were studied using light-microscopic and scanning-electron microscopic techniques. Our analysis of the specimen upon which Skinner and Pruetz (Am J Phys Anthropol 149 (2012) 468-482) had made their original observation does not support their hypothesis. We demonstrate that the enamel morphology described by them is not caused by a nonemergence of striae of Retzius ...
The systematic exhumation of mass graves is becoming a frequent occurrence globally. Historically... more The systematic exhumation of mass graves is becoming a frequent occurrence globally. Historically, it has been mostly anthropologists with their particular expertise in osteology that have been engaged by non-governmental organizations (NGO) to monitor mass grave exhumations and postmortem examinations, conducted by a host country or international forensic team, to ensure competence and a concern for justice. The excavation of graves and examination of their contents for the purposes of personal identification of victims and/or collection of evidence for prosecution require the creation of standards that meet international concerns for forensic investigation of the highest quality. However, many anthropologists are not experienced with large sites; do not have much, if any, expertise in archaeology; and are not equipped by training to assess the quality of a forensic pathologist's autopsy. This contribution is directed to both the NGO and the bio-archaeologist who are involved in the exhumation of mass graves. The experience and skills appropriate for the bio-archaeological monitor are outlined; similarly, the policies and standard operating procedures (SOP's) of the NGO that will enable the bio-archaeologist to perform their task are detailed. It is becoming increasingly clear that how a grave site was created, filled, and concealed, along with subsequent processes of site formation (e.g. slumping, robbing, animal scavenging and taphonomic alteration), require the expertise of a forensic archaeologist to discover and record site complexity along with associated forensic evidence. Similarly, the bodies themselves which are often skeletonized, fragmented and commingled pose challenges for the anthropologists and pathologists whose postmortem examinations must be critically evaluated. A model protocol for observations to make at the site as well as at the mortuary facility is provided to guide the monitor and to provide a structure for reports which are of standardized content suitable for international agencies concerned with mass grave investigation.
We describe a developmental defect that manifests as a mild constricted ''waist" in anterior teet... more We describe a developmental defect that manifests as a mild constricted ''waist" in anterior teeth from seven of nine chimpanzee individuals from Taï National Park, Côte D'Ivoire. The sample consists of 21 canine teeth and one incisor, imaged in profile with a digital microscope. Twelve teeth are affected. The waist develops during tooth formation as an external, encircling depression in the contour of the outer enamel surface, more easily seen labially. It is not a thinning of enamel per se, but rather a slight decrement in dentinal crown volume, shown in microCT scans as a change in contour of the enamel-dentin junction, spanning between 3 and 6 years of age, varying among individuals, with maximum expression at about age 4.3 years. The timing and duration of coronal waisting are consistent with descriptions of the weaning process at Taï and other chimpanzee study sites. We propose that coronal waisting records variation in the individual infant chimpanzee's physiological experiences during the process of attaining independence, increased foraging efficiency, and lactational weaning.
The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.
A geographically and temporally widespread pattern of repetitive episodes of developmental stress... more A geographically and temporally widespread pattern of repetitive episodes of developmental stress, recorded as furrows of linear enamel hypoplasia (LEH) in most recent and fossil apes, requires explanation. I compared observations of LEH recurrence among museum specimens of Pan troglodytes and Pan paniscus with historical weather records of seasonally recurrent combinations of lower temperature, higher rain and wind (“cold discomfort”). I imaged samples of 34 canine teeth (N = 20 animals, 54 independent LEH) from P. troglodytes from Fongoli, Senegal, and Tai Forest, Cote d’Ivoire and P. paniscus from the Democratic Republic of Congo with a scanning electron microscope and counted perikymata between and within LEH events. I converted counts to time using published Retzius periodicities (the number of days taken to form enamel layers, visible in thin sections) and compared their recurrence and duration to seasonal peaks of incidence and the intensity of cold discomfort. Using the longest Retzius periodicity (9 days), chimpanzees and bonobos show LEH lasting about 7–9 weeks, respectively, recurring annually. Most bonobos also show just-under semiannual recurrence of LEH. “Colder, wetter, windier” weeks recur annually at the P. troglodytes locations and semiannually at P. paniscus sites. When the combination of “below median temperatures, above median rain and winds” peaks in intensity and incidence over a 7-week period, daily “minimum hourly” temperatures average 20–21°C (7–9°C below lower critical body temperature for chimpanzees) with wind 3 times and rainfall 30 times higher than usual. These findings suggest that seasonal cold discomfort may be an important factor in episodic enamel hypoplasia in many nonhuman primates.
The original version of this article unfortunately contained mistakes in the citation in text and... more The original version of this article unfortunately contained mistakes in the citation in text and References. Author Julia Boughner's surname was inadvertently spelled as "Broughner".
The advent of markedly delayed maturation in human evolution is not known. Seasonal stress is pot... more The advent of markedly delayed maturation in human evolution is not known. Seasonal stress is potentially discernible in fossilised hard tissues and could serve as markers of the passage of absolute time. Uniform spacing between episodes of linear enamel hypoplasia (LEH) in free-ranging Pan troglodytes and Gorilla gorilla has been ascribed to semi-annual stress. We extend our study of LEH in non-human primates to Dryopithecus laietanus and D. Crusafonti from Middle to Late Miocene sites, especially Can Llobateres, from north-eastern Spain housed at the Institut de Paleontologia Dr. Crusafont (Sabadell). Of 90 teeth examined with an 8× hand lens, 46% of permanent teeth (n=78) and 8% of primary teeth (n=12) were affected by mild enamel hypoplasia. A total of 74 instances of LEH were observed. Thirty-one permanent teeth showed two or more episodes of LEH; the interval between each pair of episodes was measured with a Mitutoyo dial caliper (.05mm precision). Interval width (n=44 widths)...
For more than a century archaeologists and physical anthropologists have been engaged in the reco... more For more than a century archaeologists and physical anthropologists have been engaged in the recovery and analysis of ancient human skeletons and artifacts, in order to understand the appearance and behaviour of past peoples. Their aim, maximum information retrieval, parallels that of the police officer confronted with recent bones which might be human and possibly of forensic significance. The methods employed by archaeologists and physical anthropologists, both in the field and in the laboratory, are of immediate and obvious use to the investigating officer. Unfortunately, a gap in communication and cooperation persists between the police and the academic, to the disadvantage of both. The investigation of suspected crime can be significantly enhanced by application of the techniques of archaeological excavation. Similarly, physical anthropologists, with skills freshly honed by investigations leading to the identification of missing individuals, can turn to prehistoric and fossil b...
Discovery of a new hominin (Homo naledi) in the same geographical area as Australopithecus africa... more Discovery of a new hominin (Homo naledi) in the same geographical area as Australopithecus africanus creates the opportunity to compare developmental dental stress in higher latitude hominins with low that in latitude apes, among whom repetitive linear enamel hypoplasia (rLEH) recurs seasonally at about 6 or 12 months. In contrast to equatorial Africa, a single rainy/dry cycle occurs annually in non-coastal southern Africa. It is predicted that LEH will recur annually but not differ in duration between ancient and more recent hominins. Data were collected from epoxy casts of anterior teeth attributed to H. naledi (18 incisors, 13 canines) and A. africanus (29 incisors, 8 canines) using a digital microscope, surface scanner and scanning electron microscope. The location, number, width, depth and distance between defects (including perikymata counts and spatial measurements) of 136 LEH events were compared among crown moieties (deciles 4–6 and 7–9), tooth types and taxa. Enamel defect...
The prevalence of enamel hypoplasia in 229 Pan and Gorilla, from the Republic of Cameroon, is des... more The prevalence of enamel hypoplasia in 229 Pan and Gorilla, from the Republic of Cameroon, is described. A substantially higher proportion of gorillas (76%) than chimpanzees (58%) was affected. The incidence of enamel hypoplasia was not a function of sex, body size, or pathology. A study of tooth formation, from radiographs of a further series of immature apes, indicated that the mandibular canine bore 99% of all information about hypoplasia events. In both species a marked regularity of hypoplastic grooving with an interval of about 11.4% of canine crown height was observed. This appears to reflect a semi-annual cycle of stress which is tentatively linked to the twice-yearly rainy season. Uniform spacing of hypoplastic grooves has been observed in a variety of fossil hominids. Readily observable hypoplastic time markers in the teeth have potential for disclosing growth rates in early Hominidae. This is considered important because of the profound significance which prolonged maturation and longevity characteristic of recent human beings have for the transmission of learned behavior and social bonding.
Method, Theory, and Archaeological Perspectives, 2001
Postburial Disturbance of Graves in Bosnia-Herzegovina 15 MARK F. SKINNER HEATHER P. YORK MELISSA... more Postburial Disturbance of Graves in Bosnia-Herzegovina 15 MARK F. SKINNER HEATHER P. YORK MELISSA A. CONNOR Contents Introduction 294 Background 294 Historical Propaganda and ... Exposure of the bodies was accomplished by backhoe supplemented by shovels ...
worn mandibular le8 molars, is described in a female Native American from the Pendar Canal site (... more worn mandibular le8 molars, is described in a female Native American from the Pendar Canal site (DeRt 2). British Columbia, dating from lo90 & 130 B.P. This is thejirst archeological evidence among prehistoric peoples of cauterization as a medical treatment for infected oral tissues.
Homo erectus individual (KNM-ER 1808) from Koobi Fora, Kenya dating from I .6 + 0.1 million years... more Homo erectus individual (KNM-ER 1808) from Koobi Fora, Kenya dating from I .6 + 0.1 million years exhibits pathological apposition of bone on long bone shafts. This was originally attributed to hypervitaminosis A from the consumption of carnivore livers. Bee brood has a sufficiently high concentration of vitamin A that protracted ingestion could theoretically produce hypervitaminosis A. The ecology of the East African bee, Apir mellifera scutelatta, is investigated to show that the density of nests with their brood contents within a reasonable foraging area ofearly Homo erectus would yield an ample and reliable energy source with deleteriously high vitamin A content. A potentia1 role of honey gathering and insect larvae consumption in hominine behavioural and physical evolution is discussed.
The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.
The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check for the status of the paper. Users should always cite the published version of record.
American journal of physical anthropology, Jan 18, 2015
Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic d... more Recently, a lower than expected number of perikymata between repetitive furrow-type hypoplastic defects has been reported in chimpanzee canines from the Fongoli site, Senegal (Skinner and Pruetz: Am J Phys Anthropol 149 (2012) 468-482). Based on an observation in a localized enamel fracture surface of a canine of a chimpanzee from the Taï Forest (Ivory Coast), these authors inferred that a nonemergence of striae of Retzius could be the cause for the "missing perikymata" phenomenon in the Fongoli chimpanzees. To check this inference, we analyzed the structure of outer enamel in three chimpanzee canines. The teeth were studied using light-microscopic and scanning-electron microscopic techniques. Our analysis of the specimen upon which Skinner and Pruetz (Am J Phys Anthropol 149 (2012) 468-482) had made their original observation does not support their hypothesis. We demonstrate that the enamel morphology described by them is not caused by a nonemergence of striae of Retzius ...
The systematic exhumation of mass graves is becoming a frequent occurrence globally. Historically... more The systematic exhumation of mass graves is becoming a frequent occurrence globally. Historically, it has been mostly anthropologists with their particular expertise in osteology that have been engaged by non-governmental organizations (NGO) to monitor mass grave exhumations and postmortem examinations, conducted by a host country or international forensic team, to ensure competence and a concern for justice. The excavation of graves and examination of their contents for the purposes of personal identification of victims and/or collection of evidence for prosecution require the creation of standards that meet international concerns for forensic investigation of the highest quality. However, many anthropologists are not experienced with large sites; do not have much, if any, expertise in archaeology; and are not equipped by training to assess the quality of a forensic pathologist's autopsy. This contribution is directed to both the NGO and the bio-archaeologist who are involved in the exhumation of mass graves. The experience and skills appropriate for the bio-archaeological monitor are outlined; similarly, the policies and standard operating procedures (SOP's) of the NGO that will enable the bio-archaeologist to perform their task are detailed. It is becoming increasingly clear that how a grave site was created, filled, and concealed, along with subsequent processes of site formation (e.g. slumping, robbing, animal scavenging and taphonomic alteration), require the expertise of a forensic archaeologist to discover and record site complexity along with associated forensic evidence. Similarly, the bodies themselves which are often skeletonized, fragmented and commingled pose challenges for the anthropologists and pathologists whose postmortem examinations must be critically evaluated. A model protocol for observations to make at the site as well as at the mortuary facility is provided to guide the monitor and to provide a structure for reports which are of standardized content suitable for international agencies concerned with mass grave investigation.
We describe a developmental defect that manifests as a mild constricted ''waist" in anterior teet... more We describe a developmental defect that manifests as a mild constricted ''waist" in anterior teeth from seven of nine chimpanzee individuals from Taï National Park, Côte D'Ivoire. The sample consists of 21 canine teeth and one incisor, imaged in profile with a digital microscope. Twelve teeth are affected. The waist develops during tooth formation as an external, encircling depression in the contour of the outer enamel surface, more easily seen labially. It is not a thinning of enamel per se, but rather a slight decrement in dentinal crown volume, shown in microCT scans as a change in contour of the enamel-dentin junction, spanning between 3 and 6 years of age, varying among individuals, with maximum expression at about age 4.3 years. The timing and duration of coronal waisting are consistent with descriptions of the weaning process at Taï and other chimpanzee study sites. We propose that coronal waisting records variation in the individual infant chimpanzee's physiological experiences during the process of attaining independence, increased foraging efficiency, and lactational weaning.
The version in the Kent Academic Repository may differ from the final published version. Users ar... more The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.
A geographically and temporally widespread pattern of repetitive episodes of developmental stress... more A geographically and temporally widespread pattern of repetitive episodes of developmental stress, recorded as furrows of linear enamel hypoplasia (LEH) in most recent and fossil apes, requires explanation. I compared observations of LEH recurrence among museum specimens of Pan troglodytes and Pan paniscus with historical weather records of seasonally recurrent combinations of lower temperature, higher rain and wind (“cold discomfort”). I imaged samples of 34 canine teeth (N = 20 animals, 54 independent LEH) from P. troglodytes from Fongoli, Senegal, and Tai Forest, Cote d’Ivoire and P. paniscus from the Democratic Republic of Congo with a scanning electron microscope and counted perikymata between and within LEH events. I converted counts to time using published Retzius periodicities (the number of days taken to form enamel layers, visible in thin sections) and compared their recurrence and duration to seasonal peaks of incidence and the intensity of cold discomfort. Using the longest Retzius periodicity (9 days), chimpanzees and bonobos show LEH lasting about 7–9 weeks, respectively, recurring annually. Most bonobos also show just-under semiannual recurrence of LEH. “Colder, wetter, windier” weeks recur annually at the P. troglodytes locations and semiannually at P. paniscus sites. When the combination of “below median temperatures, above median rain and winds” peaks in intensity and incidence over a 7-week period, daily “minimum hourly” temperatures average 20–21°C (7–9°C below lower critical body temperature for chimpanzees) with wind 3 times and rainfall 30 times higher than usual. These findings suggest that seasonal cold discomfort may be an important factor in episodic enamel hypoplasia in many nonhuman primates.
The original version of this article unfortunately contained mistakes in the citation in text and... more The original version of this article unfortunately contained mistakes in the citation in text and References. Author Julia Boughner's surname was inadvertently spelled as "Broughner".
The advent of markedly delayed maturation in human evolution is not known. Seasonal stress is pot... more The advent of markedly delayed maturation in human evolution is not known. Seasonal stress is potentially discernible in fossilised hard tissues and could serve as markers of the passage of absolute time. Uniform spacing between episodes of linear enamel hypoplasia (LEH) in free-ranging Pan troglodytes and Gorilla gorilla has been ascribed to semi-annual stress. We extend our study of LEH in non-human primates to Dryopithecus laietanus and D. Crusafonti from Middle to Late Miocene sites, especially Can Llobateres, from north-eastern Spain housed at the Institut de Paleontologia Dr. Crusafont (Sabadell). Of 90 teeth examined with an 8× hand lens, 46% of permanent teeth (n=78) and 8% of primary teeth (n=12) were affected by mild enamel hypoplasia. A total of 74 instances of LEH were observed. Thirty-one permanent teeth showed two or more episodes of LEH; the interval between each pair of episodes was measured with a Mitutoyo dial caliper (.05mm precision). Interval width (n=44 widths)...
For more than a century archaeologists and physical anthropologists have been engaged in the reco... more For more than a century archaeologists and physical anthropologists have been engaged in the recovery and analysis of ancient human skeletons and artifacts, in order to understand the appearance and behaviour of past peoples. Their aim, maximum information retrieval, parallels that of the police officer confronted with recent bones which might be human and possibly of forensic significance. The methods employed by archaeologists and physical anthropologists, both in the field and in the laboratory, are of immediate and obvious use to the investigating officer. Unfortunately, a gap in communication and cooperation persists between the police and the academic, to the disadvantage of both. The investigation of suspected crime can be significantly enhanced by application of the techniques of archaeological excavation. Similarly, physical anthropologists, with skills freshly honed by investigations leading to the identification of missing individuals, can turn to prehistoric and fossil b...
Discovery of a new hominin (Homo naledi) in the same geographical area as Australopithecus africa... more Discovery of a new hominin (Homo naledi) in the same geographical area as Australopithecus africanus creates the opportunity to compare developmental dental stress in higher latitude hominins with low that in latitude apes, among whom repetitive linear enamel hypoplasia (rLEH) recurs seasonally at about 6 or 12 months. In contrast to equatorial Africa, a single rainy/dry cycle occurs annually in non-coastal southern Africa. It is predicted that LEH will recur annually but not differ in duration between ancient and more recent hominins. Data were collected from epoxy casts of anterior teeth attributed to H. naledi (18 incisors, 13 canines) and A. africanus (29 incisors, 8 canines) using a digital microscope, surface scanner and scanning electron microscope. The location, number, width, depth and distance between defects (including perikymata counts and spatial measurements) of 136 LEH events were compared among crown moieties (deciles 4–6 and 7–9), tooth types and taxa. Enamel defect...
The prevalence of enamel hypoplasia in 229 Pan and Gorilla, from the Republic of Cameroon, is des... more The prevalence of enamel hypoplasia in 229 Pan and Gorilla, from the Republic of Cameroon, is described. A substantially higher proportion of gorillas (76%) than chimpanzees (58%) was affected. The incidence of enamel hypoplasia was not a function of sex, body size, or pathology. A study of tooth formation, from radiographs of a further series of immature apes, indicated that the mandibular canine bore 99% of all information about hypoplasia events. In both species a marked regularity of hypoplastic grooving with an interval of about 11.4% of canine crown height was observed. This appears to reflect a semi-annual cycle of stress which is tentatively linked to the twice-yearly rainy season. Uniform spacing of hypoplastic grooves has been observed in a variety of fossil hominids. Readily observable hypoplastic time markers in the teeth have potential for disclosing growth rates in early Hominidae. This is considered important because of the profound significance which prolonged maturation and longevity characteristic of recent human beings have for the transmission of learned behavior and social bonding.
Method, Theory, and Archaeological Perspectives, 2001
Postburial Disturbance of Graves in Bosnia-Herzegovina 15 MARK F. SKINNER HEATHER P. YORK MELISSA... more Postburial Disturbance of Graves in Bosnia-Herzegovina 15 MARK F. SKINNER HEATHER P. YORK MELISSA A. CONNOR Contents Introduction 294 Background 294 Historical Propaganda and ... Exposure of the bodies was accomplished by backhoe supplemented by shovels ...
worn mandibular le8 molars, is described in a female Native American from the Pendar Canal site (... more worn mandibular le8 molars, is described in a female Native American from the Pendar Canal site (DeRt 2). British Columbia, dating from lo90 & 130 B.P. This is thejirst archeological evidence among prehistoric peoples of cauterization as a medical treatment for infected oral tissues.
Homo erectus individual (KNM-ER 1808) from Koobi Fora, Kenya dating from I .6 + 0.1 million years... more Homo erectus individual (KNM-ER 1808) from Koobi Fora, Kenya dating from I .6 + 0.1 million years exhibits pathological apposition of bone on long bone shafts. This was originally attributed to hypervitaminosis A from the consumption of carnivore livers. Bee brood has a sufficiently high concentration of vitamin A that protracted ingestion could theoretically produce hypervitaminosis A. The ecology of the East African bee, Apir mellifera scutelatta, is investigated to show that the density of nests with their brood contents within a reasonable foraging area ofearly Homo erectus would yield an ample and reliable energy source with deleteriously high vitamin A content. A potentia1 role of honey gathering and insect larvae consumption in hominine behavioural and physical evolution is discussed.
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