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Lower jaws (containing the teeth), eyes, and skin samples were collected from harp seals (Pagophilus groenlandicus) in the southeastern Barents Sea for the purpose of comparing age estimates obtained by 3 different methods, the traditional technique of counting growth layer groups (GLGs) in teeth and 2 novel approaches, aspartic acid racemization (AAR) in eye lens nuclei and telomere sequence analyses as a proxy for telomere length. A significant correlation between age estimates obtained using GLGs and AAR was found, whereas no correlation was found between GLGs and telomere length. An AAR rate ([k.sub.Asp]) of 0.00130/year [+ or -] 0.00005 SE and a D-enantiomer to L-enantiomer ratio at birth (D/[L.sub.o] value) of 0.01933 [+ or -] 0.00048 SE were estimated by regression of D/L ratios against GLG ages from 25 animals (12 selected teeth that had high readability and 13 known-aged animals). AAR could prove to be useful, particularly for ageing older animals in species such as harp seals where difficulties in counting GLGs tend to increase with age. Age estimation by telomere length did not show any correlation with GLG ages and is not recommended for harp seals. DOI: 10.1644/10-MAMM-A-080.1. Key words: age determination, age estimation, amino acid racemization (AAR), aspartic acid, eye lens, growth layer group (GLG), Pagophilus groenlandicus, population management, telomere

Developing teeth are used to assess maturity and estimate age in several disciplines. The aim of the study was to determine which of the most well known dental age estimation methods was best at estimating age. The target sample of dental radiographs (N = 946, ages 3-16) was described by Maber et al. (Forensic Sci Int 159 (2006) S68-S73). Seven mandibular permanent teeth ([I.sub.1]-[M.sub.2]) were assessed, and dental age was calculated using four dental maturity scales and fifteen methods that use data for individual teeth. The mean difference between dental age and real age was calculated (bias) as well as several other measures of accuracy (mean/median absolute difference, percentage aged to within six months and to within 10% of real age). Most methods estimated age with significant bias and standard deviation of bias ranged from 0.86 to 1.03 years. Analysis by age group showed most methods over-aged younger children, and considerably under-aged older children. The method that performed best was the dental maturity scale of Willems et al. (J Forensic Sci 46 (2001) 893-895) with bias of -0.14 [+ or -] 0.86 years (N = 827), mean absolute difference of 0.66 years, 71% aged to 10% or less of age, and 49% aged to within six months. Two individual teeth, [P.sub.2] and [M.sub.2], estimated age with bias not significantly different to zero for most formation stages using methods based on a large reference sample (L9a Demirjian stages) and a uniform age distribution (N25a Moorrees stages). Standard deviation of bias was least for early crown stages and most for late root stages. Methods that average ages for individual teeth improve if schedules for 'mean age entering a stage' are adjusted for prediction. Methods that directly calculate 'mean age within stage' can be improved by drawing from a uniform age distribution. Am J Phys Anthropol 143:545-554, 2010. [c] 2010 Wiley-Liss, Inc. KEY WORDS dental age; age determination; radiograph; crown; root DOI 10.1002/ajpa.21349

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.04.042 Byline: James M. Lewis (a), David R. Senn (b) Keywords: Forensic odontology; Dental age estimation; Third molars Abstract: When an individual reaches the age of legal majority, their treatment within the criminal and civil legal systems is changed dramatically in the United States. Forensic odontologists are often asked to assist government agencies in estimating the ages of persons who may or may not have reached that legally important age. The third molars are the only teeth useful as forensic estimators of chronological age in the target age group. This study reviews the principles, methodology, and population data of the most commonly used technique in the United States, the analysis of the third molar development based on modified Demirjian staging. The method analyzes the developing third molar to estimate mean age, age intervals and the empirical probability that an individual has reached the anniversary of her or his eighteenth birthday. Author Affiliation: (a) Center for Education and Research in Forensics, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA (b) Center for Education and Research in Forensics, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MC 7919, San Antonio, TX 78229-3900, USA Article History: Received 31 March 2010; Revised 22 April 2010; Accepted 25 April 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.04.019 Byline: M. Van Vlierberghe (a), E. BoAtacz-Rzepkowska (b), L. Van Langenhove (c), J. Aaszkiewicz (b), B. Wyns (d), D. Devlaminck (d), L. Boullart (d), P. Thevissen (a), G. Willems (a) Keywords: Gleiser and Hunt; Age estimation; Polish population; Third molar development; Orthopantomogram; Regression formulae Abstract: The aim of this study was to establish a third molar developmental database to model dental age of Polish youngsters, to investigate the rating level of the scores when dividing a year interval into a quarter of a year and to examine sex differences, left-right and upper-lower jaw asymmetry. Author Affiliation: (a) School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Department of Forensic Odontology, Katholieke Universiteit Leuven, Kapucijnenvoer 7, B 3000 Leuven, Belgium (b) Department of Conservative Dentistry, Endodontics and Periodontology, Medical University of AodA*, 92-216 AodA*, Pomorska 251, Poland (c) Department of Textiles, Ghent University, Technologiepark 907, 9052 Zwijnaarde, Belgium (d) Department of Electrical Energy, Systems and Automation, Ghent University, Technologiepark 913, 9052 Zwijnaarde, Belgium Article History: Received 16 March 2010; Accepted 11 April 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.02.032 Byline: H.M. Liversidge Keywords: Demirjian's method; Dental maturation; Dental age estimation; Radiograph Abstract: Although Demirjian's method is designed to assess dental maturity at the individual level, significant differences between average dental age and real age for groups have been interpreted as population differences. The aim of this study was to describe the variation in maturity score for age and age for maturity score from a large collaborative database of children and discuss methods adapted for groups in light of this. Tooth stages from radiographs of 4710 males and 4661 females (age 2-18) were used and dental maturity scores calculated using Demirjian and Goldstein . The mean, standard deviation, standard error and 95% confidence intervals of maturity score by age group (6 and 12 months groups) and age by maturity score (5 points) groups were calculated. Adapted maturity curves from 13 published studies of boys from Europe, Middle East, Africa, India, China and South America were compared to the database. Most adapted curves at the 50th percentile from world regions fell within the 95% confidence intervals. Those that did not, were hampered by small sample size or poorly fitting curves. This is complicates by the inclusion of mature individuals. Few studies adapting Demirjian's method provide sufficient or appropriate statistics to compare maturation of individual teeth. The wide 95% confidence intervals for maturity score by age, age by maturity score, age of individual tooth stages and large number of sequences suggest that the significant differences in dental maturity score do not reflect any biological difference in the timing of tooth formation stages at the population level. Demirjian's dental maturity method is inappropriate to assess population differences in dental maturity and adapting scores for age or age for scores for different groups of children is probably unnecessary. Author Affiliation: Queen Mary University of London, Barts & The London School of Medicine and Dentistry, Institute of Dentistry, Turner Street, London E1 2AD, United Kingdom Article History: Received 12 February 2010; Accepted 23 February 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.03.026 Byline: Niels Lynnerup (a), Henrik Kjeldsen (b), Ralf Zweihoff (c), Steffen Heegaard (d), Christina Jacobsen (a), Jan Heinemeier (b) Keywords: Age at death; Forensic; Chronology; Radiocarbon Abstract: Based on an actual case, where we were able to ascertain the year of birth of three dead babies found in a deep-freezer to within 1-2 years (1986, 1988 and 2004, respectively), we review the current state of forensic age determination/year of birth determination. The age of an individual (year of birth) is often a fundamental piece of data in connection with forensic identification of unidentified bodies. The methods most often used are based on determining various morphological, age-related, changes on the skeleton (or teeth, although odontological methods are not reviewed in this paper). As such, these methods are all relative, i.e. they do not furnish calendar ages or years, but an estimate of the age at death, with a rather large range, i.e. the methods rely on biological aging following the chronological aging. More recently, methods have been proposed using more direct ascertainment of age at death, e.g. protein racemisation, or, as in our case, radiocarbon methods. Especially the latter method may in fact yield absolute ages (years of birth), because.sup.14C activity, as measured in specific proteins in specific cells or tissues in the body, were in equilibrium with the so-called bomb-pulse, when these proteins were formed (at birth). The bomb pulse reflects a dramatic change in atmospheric.sup.14C content due to nuclear bomb testing, and these dramatic changes can be rather tightly related to single calendar years. Author Affiliation: (a) Department of Forensic Medicine, Faculty of Health Sciences, University of Copenhagen, Denmark (b) AMS.sup.14C Dating Centre, Department of Physics and Astronomy, Aarhus University, Denmark (c) Institute of Legal Medicine, Dortmund, Germany (d) Eye Pathology Section, Faculty of Health Sciences, University of Copenhagen, Denmark Article History: Received 19 January 2010; Revised 17 March 2010; Accepted 19 March 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.04.040 Byline: P.W. Thevissen (a), A. Alqerban (b), J. Asaumi (c), F. Kahveci (d), J. Kaur (a), Y.K. Kim (e), P. Pittayapat (a), M. Van Vlierberghe (a), Y. Zhang (f), S. Fieuws (g), G. Willems (a) Keywords: Forensic odontology; Age determination by teeth; Third molars; Country specific populations; Bayesian; Accuracy Abstract: Unquestionable forensic age investigations are based on statistical models constructed on a sample containing subjects of identical origin as the examined individual. In cases where corresponding models are unavailable, the established report has to describe the possible effects of this unrelated information on the predicted age outcome. The aim of this study is to collect country specific databases of third molar development and to verify how the related dental age estimations are influenced if we were to use dental developmental information only from Belgium or from all collected countries together. Data containing third molar developmental stages scored following Gleiser and Hunt (modified by Kohler) were collected from 9 country specific populations (Belgium, China, Japan, Korea, Poland, Thailand, Turkey, Saudi-Arabia and South-India). Age predictions were obtained from a training dataset and validated on a test dataset. Bayes rule using the repeated third molar scores is applied to get age predictions and prediction intervals. Three age predictions were compared for males and females separately. For the first prediction, the training dataset contains only Belgian subjects. For the second prediction, the training dataset for each country consists only of subjects of the country itself. For the final prediction, subjects from all countries are pooled into one common training dataset. Besides the (absolute) difference between the chronological age and the predicted age, specific interest lies in the juvenile-adult distinction. In the age range from 16 to 22 years 6982 subjects (3189 male and 3793 female) were analyzed. Using information on third molar development from Belgium compared to information from the country specific databases hardly increased the mean absolute differences (MAD) and mean squared errors (MSE): the MAD and MSE increased on average with 0.5 and 2.5 months with maximal increases of, respectively 1.6 and 7.3 months. Using information from all countries pooled compared to country specific information provided even on average negligible increases (0.05 and 0.2 months for MAD and MSE, respectively). For the juvenile-adult discrimination, using information from all countries instead of country specific information yielded comparable performances. Using Belgium instead of country specific information increased the percentage of correctly identified juveniles, but decreased the percentage of correctly identified adults. The adult-juvenile discrimination based on information used from Belgium provides judicially the best applied reference. Author Affiliation: (a) Katholieke Universiteit Leuven, Faculty of Medicine, School of Dentistry, Forensic Odontology Department, Kapucijnenvoer 7, Leuven B-3000, Belgium (b) Riiyadh Military Hospital (RKH), Dental Department, Building 131, Riyadh, Saudi Arabia (c) Department of Oral and Maxillofacial Radiology, Field of Tumor Biology, Okayama University Graduate School of Medicine and Dentistry, 5-1, Shikata-cho, 2-Chome, Okayama 700-8525, Japan (d) Gulumse Agiz Ve Dis Sagligi Klinigi, Perpa t.m. b blok kat:8, Okmeydani, Sisli, Turkey (e) Department of Oral Medicine and Oral Diagnosis, School of Dentistry & Dental Research Institute, Seoul National University, Yunkeon-Dong 28, Chongro-Ku, Seoul 110-749, Republic of Korea (f) Dalian Stomatological Hospital, No. 959 Changjiang Road, Shahekou District 116021, PR China (g) I-BioStat, Katholieke Universiteit Leuven and Universiteit Hasselt. Kapucijnenvoer 35, Blok D, bus 7001, B-3000 Leuven, Belgium Article History: Received 16 March 2010; Revised 20 April 2010; Accepted 25 April 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2010.04.054 Byline: P.W. Thevissen (a), S. Fieuws (b), G. Willems (a) Keywords: Forensic odontology; Third molars development; Country specific populations; Ethnicity; Age determination by teeth Abstract: The majority of age estimation models based on third molar development are constructed on samples from populations with described and outlined origin. Due to unlike research protocols these studies can rarely be compared for the evaluation of possible geographical or ethnical influences on third molar development. The aim of this study is to evaluate country specific third molar development on standardized collected and analyzed data. On panoramic radiographs selected from subjects out of 9 country specific populations (Belgium, China, Japan, Korea, Poland, Thailand, Turkey, Saudi-Arabia and South-India) the four third molar scores were registered, according to a modified Gleiser and Hunt methodology. To obtain for each subject a (factor) score which represents the degree of third molar development, a generalized linear mixed model for multivariate ordinal data was fitted on the repeated third molar scores. Differences between countries are analyzed using gender-specific regression models for these factor scores with age and country as predictors. Comparisons between countries revealed differences in speed and onset of development. However, although reaching statistical significance, differences in actual value were small and not constant over the considered age range. In all countries, at all ages, males were ahead in third molar development compared to females. Author Affiliation: (a) Katholieke Universiteit Leuven, Faculty of Medicine, School of Dentistry, Forensic Odontology Department, Kapucijnenvoer 7, Leuven B-3000, Belgium (b) I-BioStat, Katholieke Universiteit Leuven and Universiteit Hasselt, Kapucijnenvoer 35, Blok D, bus 7001, Leuven B-3000, Belgium Article History: Received 31 March 2010; Revised 24 April 2010; Accepted 29 April 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.09.008 Byline: E. Cunha (a), E. Baccino (b), L. Martrille (b), F. Ramsthaler (c), J. Prieto (d), Y. Schuliar (e), N. Lynnerup (f), C. Cattaneo (g) Keywords: Aging; Forensic anthropology; Forensic odontology; Human remains; Living; FASE (Forensic Anthropology Society of Europe) Abstract: Forensic anthropology is affected by the unavoidable limits concerning difficulties in standardization of methods and procedures; age estimation is one of the main tasks of forensic anthropology and odontology, both on the dead and the living: literature has shown several methods of age estimation, and although they may be thought of as equivalent, every procedure has its limits, mean error, practical situation and age range where it gives the best results; the lack of standardization and consensus concerning which method can be used, as well as the lack of a practical approach in different cases is the main limit in a correct age estimation process. This review aims at exposing the experience of the authors working in the FASE (Forensic Anthropology Society of Europe) subsection of IALM (International Academy of Legal Medicine) in the field of age estimation both on the dead and the living, at highlighting advantages and limits of each method, and suggesting practical solutions concerning the age estimation process for adults and subadults, dead and living, and pedopornographic material. Author Affiliation: (a) Department of Anthropology, Instituto Nacional de Medicina Legal, University of Coimbra, Largo da Se-Nova, 3000 Coimbra, Portugal (b) Service de Medecine Legale, Centre Hospitalier Universitaire, Hopital Lapeyronie, Avenue du Doyen Gaston Giraud, 34295 Montpellier, Cedex 5, France (c) Department of Legal Medicine, University of Frankfurt/Main, Kennedyallee 104, 60596 Frankfurt/Main, Germany (d) Laboratory of Forensic Anthropology and Odontology, Instituto AnatA[sup.2]mico Forense de Madrid, Ciudad Universitaria, Avenida Complutense, 28040 Madrid, Spain (e) Service de sante des armees, Institut de Recherche Criminelle de la Gendarmerie Nationale, 1, Bd Theophile Sueur, 93111 Rosny-sous-bois, France (f) Section of Forensic Pathology, Department of Forensic Medicine, University of Copenhagen, Frederik d. 5s Vej 11, DK-2100 A Copenhagen, Denmark (g) LABANOF, Laboratorio di Antropologia ed Odontologia Forense, Dipartimento di Morfologia Umana e Scienze Biomediche, Sezione di Medicina Legale, Universita degli Studi di Milano, Via Mangiagalli 37, 20133 Milan, Italy Article History: Received 5 January 2009; Revised 8 September 2009; Accepted 14 September 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.05.023 Byline: U. Baumann (a), R. Schulz (b), W. Reisinger (c), A. Heinecke (d), A. Schmeling (b), S. Schmidt (a) Keywords: Forensic age estimation; Skeletal age; Radius; Ulna Abstract: Hand radiographs from 554 male and 288 female subjects aged 10-30 years, which had been taken due to traumatological indications, were evaluated. A classification into five ossification stages was applied to assess the epiphyseal development of distal radius and distal ulna (1: epiphysis not ossified; 2: epiphysis ossified, nonunion of the epiphysis and metaphysis; 3: partial union of the epiphysis and metaphysis; 4: complete union of the epiphysis and metaphysis, epiphyseal scar visible; 5: complete union of the epiphysis and metaphysis, epiphyseal scar nondiscernable). It was established that male subjects with an ossification stage 4 of the radius or ulna and female subjects with an ossification stage 5 of the radius were at least 14 years old. The occurrence of ossification stage 5 of the radius proves that a male individual has reached the age of 18 years. Author Affiliation: (a) Institut fur Rechtsmedizin, Charite - Universitatsmedizin Berlin, Turmstrasse 21, 10553 Berlin, Germany (b) Institut fur Rechtsmedizin, Universitatsklinikum Munster, Rontgenstrasse 23, 48149 Munster, Germany (c) Institut fur Radiologie (CCM), Charite - Universitatsmedizin Berlin, Schumannstrasse 20/21, 10117 Berlin, Germany (d) Institut fur Medizinische Informatik und Biomathematik, Universitatsklinikum Munster, DomagkstraAe 9, 48149 Munster, Germany Article History: Received 24 August 2008; Revised 17 February 2009; Accepted 30 May 2009

A new method for estimating adult age-at-death from the first rib was developed as a modification of the Kunos et al. (Am J Phys Anthropol 110 (1999) 303-323) method. Data were collected on three aspects of the first rib (costal face, rib head, and tubercle facet) for 470 known-age males of Balkan ancestry collected as evidence during investigations conducted by the International Criminal Tribunal for the former Yugoslavia (ICTY). Ages-at-death range from 12 to 90 years (mean of 47.7 years). Several variables were extracted from the original study utilizing all three skeletal aspects of the first rib. This list was modified to 11 variables as preliminary tests on seriations of the samples were undertaken. A cumulative probit model with age measured on a log scale was used to calculate the mean and standard deviation of the ages-of-transition for each component. Multi-variate analysis of the three components was also performed. The lowest correlation (r = 0.079, controlling for age) was between the geometric shape of the costal face and the surface texture of the tubercle facet. Assuming a correlation of zero, these two traits were used to calculate the highest posterior density regions for estimating individual ages-at-death. Age-at-death estimates generated from 50 and 95% posterior density regions indicate that this method captures age-related change reaching the ninth decade. The Bayesian statistical approach used here produced a valuable and promising new method for estimating age-at-death. Additional research is necessary to determine if these highest posterior density regions produce results highly correlated with age in other samples and its applicability to females. KEY WORDS age estimation; forensic anthropology; bioarcheology; transition analysis; paleodemography

This study completes previously reported ages for timing of epiphyseal union in the post-cranial skeleton in a recent sample, with data from the scapula, clavicle, humerus, radius, and ulna. A sample of 121 individuals between the ages of 9 and 29 (females = 65, males = 56) was derived from the Lisbon documented skeletal collection. Epiphyseal union was scored at 16 anatomical locations, using a three-stage scheme: 1) no union; 2) partial union; and 3) completed union, all traces of fusion having disappeared. In the upper limb, the epiphyses of the elbow are the first to fuse at around 11 to 15 years of age, followed by those of the shoulder and wrist. In the scapular girdle, the coracoid area is the first to fuse, followed by the glenoid surface and remaining epiphyses, with the medial clavicle fusing last, by the age of 25-27. There is a sex difference in maturation, with females showing an advance relative to males of about 2 years in the upper limb. Sex differences in maturation are less noticeable in the scapular girdle, but data suggest that females are also ahead of males. Results suggest overall similar age ranges for stages of union as previous dry bone observations, but some studies show significant divergences which seem to derive from methodological issues. Although some radiographic reference standards provide comparable age ranges, they should probably be avoided when aging skeletal remains. KEY WORDS skeletal age; bone maturation; dry bone; Lisbon collection

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2007.03.013 Byline: Roberto Cameriere (a), Luigi Ferrante (b) Keywords: Age determination; Carpals; Teeth; Linear regression; Illegal immigration Abstract: Estimation of skeletal age using radiographic images is widely used in assessing biological growth in clinical and auxological studies. The most frequently used areas for age estimation in children and adolescents are tooth and wrist/hand, both giving good results with only a low level of radiation. This pilot study of a sample of 150 Italian children and adolescents aged between 5 and 15 years focused on analyzing the possible applications of the proportion of carpal area (Ca) and teeth mineralization as a criterion of age estimation. The regression model, describing age as a linear function of gender (g), the ratio between carpal bones area and carpal area (Bo/Ca) and the measurement of open apices, yielded the following equation: Age=4.619+0.401g+0.551N.sub.0-0.647s+7.163Bo/Ca-0.123N.sub.0s. The model explained 93% of the total variance (R.sup.2 =0.93), the median of the absolute values of residuals (observed age minus predicted age) was 0.465 years, with an inter-quartile range (IQR) equalling 0.529 years, and a standard error of estimate of 0.73 years. Author Affiliation: (a) Institute of Legal Medicine, University of Macerata, Via D. Minzoni 9, 62100 Macerata, Italy (b) Institute of Biochemical Biotechnologies, Faculty of Medicine, Polytechnical University of Marches, via Ranieri 65, 60100 Ancona, Italy Article History: Received 13 October 2006; Revised 1 February 2007; Accepted 15 March 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2007.03.009 Byline: Stella Martin-de las Heras (a), Pedro Garcia-Fortea (b), Angie Ortega (a), Sara Zodocovich (c), Aurora Valenzuela (a) Keywords: Forensic odontology; Dental age estimation; Third molar mineralization; Ethnicity Abstract: Spain is frequently the entrance country into the European Union for undocumented immigrants, especially those from the Magreb (Northern Africa). Forensic age estimates for these persons are difficult because systematic studies of dental maturity are lacking. Three different populations were analyzed to determine the pattern of development of third molars as a tool for age estimation in people of different ethnic and geographic origin. Orthopantomograms from two different populations of Spanish origin (Galicia in northwestern continental Spain, and Ceuta, a Spanish province in Northern Africa) were compared to radiographs of molars from a Magrebian population (Northern Africa) resident in Ceuta. Orthopantomograms were obtained from a private dental clinic (n =344) in Galicia and from the Public Oral Health Services (n =228) in Ceuta. We looked for differences in third molar mineralization (determined with the Demirjian scale) that might serve as age indicators (older versus younger than 18 years). Differences in maturation patterns were found between sexes and populations of origin. Mineralization of tooth 38 was more advanced in males than females among subjects 18 years of age and older in all three populations. Moreover, mineralization of tooth 38 in subjects aged 18 years and older was significantly slower in the Spanish-Galicia population than in the Magrebian-Ceuta population. We found no significant differences between Magrebian and Spanish individuals from Ceuta. We conclude that differences in tooth 38 mineralization may be related more with socio-geographical than ethnic origin (ancestry), and thus constitute evidence of the relevance of socio-geographic rather than genetic factors in third molar development. We used ROC analysis to determine the accuracy of the examiner's ability to correctly estimate age as younger or older than 18 years. The results suggest that Demirjian stage for tooth 38 can be considered a good indicator of age in all three populations. Author Affiliation: (a) Department of Forensic Medicine and Forensic Odontology, University of Granada, Avenida de Madrid 11, 18071 Granada, Spain (b) Health Department, Government Office, Malaga, Spain (c) Private Dental Practice, Ferrol, Spain Article History: Received 5 March 2007; Accepted 13 March 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2006.08.023 Byline: Stefan Strasser (a), Albert Zink (a), Gerald Kada (c), Peter Hinterdorfer (c), Oliver Peschel (d), Wolfgang M. Heckl (a)(b), Andreas G. Nerlich (e), Stefan Thalhammer (a)(f) Keywords: AFM; Force spectroscopy; Forensic medicine; Age determination; Blood spots Abstract: We present a new tool for the estimation of the age of bloodstains, which could probably be used during forensic casework. For this, we used atomic force microscopy (AFM) for high-resolution imaging of erythrocytes in a blood sample and the detection of elasticity changes on a nanometer scale. For the analytic procedure we applied a fresh blood spot on a glass slide and started the AFM detection after drying of the blood drop. In a first step, an overview image was generated showing the presence of several red blood cells, which could easily be detected due to their typical 'doughnut-like' appearance. The consecutively morphological investigations in a timeframe of 4 weeks could not show any alterations. Secondly, AFM was used to test the elasticity by recording force-distance curves. The measurements were performed immediately after drying, 1.5h, 30h and 31 days. The conditions were kept constant at room temperature (20[degrees]C) and a humidity of 30%. The obtained elasticity parameters were plotted against a timeline and repeated several times. The elasticity pattern showed a decrease over time, which are most probably influenced by the alteration of the blood spot during the drying and coagulation process. The preliminary data demonstrates the capacity of this method to use it for development of calibration curves, which can be used for estimation of bloodstain ages during forensic investigations. Author Affiliation: (a) Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universitat, Munich, Germany (b) Deutsches Museum, Museumsinsel 1, Munich, Germany (c) Institute for Biophysics, Johannes-Kepler-University, Linz, Austria (d) Department of Forensic Medicine, Ludwig-Maximilians University, Munich, Germany (e) Department of Pathology, Academic Hospital Munich-Bogenhausen, Germany (f) Institute of Radiation Protection, GSF-National Research Center for Environment and Health, Germany Article History: Received 16 February 2006; Revised 7 July 2006; Accepted 30 August 2006

To study forest dynamics without relying on the space-for-time substitution, one must be able to follow a population or stand of trees back or forward in time. The method of stand reconstruction looks back in time by aging all the live trees and aging and dating the time of death of dead standing and fallen trees. However, dead trees are lost by decomposition so the record becomes increasingly incomplete with passage of time. Here we present a model of the passage of trees from dead standing to dead decomposed but still datable to completely decomposed and thus undatable or lost. We then generalize a method for calculating the falling rate of dead trees originally proposed in 1985 by A. P. Gore, E. A. Johnson, and H. P. Lo. We do this by removing the assumption that no trees are lost by decomposition, i.e., by using the decomposition rate. Finally, in the most important result, the model allows estimation of how far back a good estimate of the numbers in the population can be made if the decomposition rates are known. Key words: dead tree falling rate; dendrochronology; forest reconstruction; log decay rate; stand history; stand reconstruction; succession; tree populations.

Because absolute mammalian age is difficult to measure directly, various methods have been used for its estimation. Among these methods, the degree of molar eruption and wear are considered to be the most reliable indicators of relative age. We used the nature and extent of maxillary molar toothrow eruption and wear to assign individuals of the solitary South African endemic Cape dune mole-rat (Bathyergus suillus) collected from a single population on the grounds of Cape Town International Airport, Cape Town, South Africa, to 9 relative age classes. We then used cranial morphometric analysis, and for comparative purposes, an assessment of the nature and extent of variation in body mass and body length, to investigate the nature and extent of sexual dimorphism and age variation in this little-studied species of mole-rat. Both univariate and multivariate analyses distinguished relative age classes 2 and 3 from 6-9, but age classes 4 and 5 were intermediate between the 2 other age-class groupings, suggesting that individuals of age classes 4 and 5 may be at a point on a hypothetical growth curve where the curve begins to stabilize. Examination of our data showed the absence of sexual dimorphism in younger individuals of age classes 2-5, and its presence in older individuals of age classes 6-9. Together with a proposed study of microsatellites, our analyses may improve our understanding of the population structure of the Cape dune mole-rat. Key words: age variation, Bathyergus suillus, body mass/length, Cape dune mole-rat, cranial morphology, molar morphology, morphometrics, sexual dimorphism, southern Africa

Patterns of growth and development provide information critical for documenting population demographics. Herein we document the reproductive biology for and provide equations that accurately predict the ages of 2 widely sympatric species of bats from central Indiana--the northern myotis (Myotis septentrionalis) and the little brown myotis (Myotis lucifugus). Young of M. septentrionalis were born synchronously (within a 6-day period) and within a narrow size range (mean length of forearm = 12.78 mm, 95% confidence interval [95% CI] = [+ or -] 0.52 mm; mass = 1.91 g, 95% CI = [+ or -] 0.11 g). Young of M. lucifugus were born during a 42-day period and within a narrow size range (mean length of forearm = 14.26 mm, 95% CI = [+ or -] 0.23 mm; mean body mass = 2.19 g, 95% CI = [+ or -] 0.08 g). Young of M. septentrionalis were born significantly smaller (t = 4.52, d.f. = 137, P < 0.001) and lighter (t = 2.57, d.f. = 137, P < 0.05) than were young of M. lucifugus. We developed species-specific equations that made it possible to estimate the age of both species of bat to within 1 day. These results indicate that similar-sized and closely related bats grow at comparable rates and provide the 1st detailed information about reproductive biology of M. septentrionalis. Key words: bats, demographics, growth models, Myotis lucifugus, Myotis septentrionalis, reproduction

New Zealand fur seals (Arctocephalus forsteri) are common in the Australian-New Zealand region, but vital demographic data are lacking. Accurate determination of the age of individuals is critical to the study of age-specific life-history parameters. A cross-sectional sample of female and male New Zealand fur seals was caught and animals were individually marked on Kangaroo Island, South Australia, between 2000 and 2003. Seals were aged through examination of a postcanine tooth, which was removed from each animal. Annual formation of cementum layers was confirmed and accuracy in age estimation was determined by examination of teeth removed from individuals of known age. Indirect methods of assessing reproductive maturity based on characteristics of mammary teats indicated that females 1st gave birth between 4 and 8 years of age, with an average age at reproductive maturity (ARM) of 5 years. No females were observed to breed beyond 22 years. Age of 1st territory tenure in males ranged from 8 to 10 years. Variation in ARM between individuals appears to be related in part to body size and condition. Classification of mammary teat status in combination with techniques for aging live animals provided a means of assessing ARM in the absence of extensive longitudinal data. Key words: age estimation, Arctocephalus forsteri, cementum, longevity, reproduction

Histological methods for the estimation of age at death using cortical bone are based on the evaluation of microstructural changes over time. Since histological analysis is a destructive method, most techniques attempt to limit the amount of cortical bone needed for analysis. Sample location, however, can have a significant effect on the accuracy of these methods. Furthermore, research demonstrates that both intersection and intrasection variation is present at the midshaft of the femur, which is the primary location for estimating age at death in humans. This research determines the extent of regional variation within the adult human femur and its effect on age estimation. Secondary osteon lamellae and Haversian canal ratio and cortical thickness were quantified. Thompson's All Males Left Femur regression equation was used to estimate age. Results show that significant regional variation occurs in the estimated ages derived from the posterior aspect of the femoral shaft and significant intrasection variation occurs in age estimates from the mid and mid-distal cross-sections. Thus, the inter and intrasection variation that occurs in bone remodeling within the femoral cortex has the potential to produce significant differences amongst age estimates taken from various femoral diaphyseal locations compared to the age estimated from the standard location used in Thompson's core method (1978). The results indicate that the use of this histological method is dependant on the ability to correctly identify the four anatomical locations, but the extracted core used for age estimation is not necessarily confined to the anterior midshaft. KEY WORDS forensic anthropology; age estimation; histomorphology; osteon

Comparison of different adult age estimation methods on the same skeletal sample with unknown ages could forward paleodemographic inference, while researchers sort out various controversies. The original aging method for the auricular surface (Lovejoy et al., 1985a) assigned an age estimation based on several separate characteristics. Researchers have found this original method hard to apply. It is usually forgotten that before assigning an age, there was a seriation, an ordering of all available individuals from youngest to oldest. Thus, age estimation reflected the place of an individual within its sample. A recent article (Buckberry and Chamberlain, 2002) proposed a revised method that scores theses various characteristics into age stages, which can then be used with a Bayesian method to estimate an adult age distribution for the sample. Both methods were applied to the adult auricular surfaces of a Pre-Columbian Maya skeletal population from Copan, Honduras and resulted in age distributions with significant numbers of older adults. However, contrary to the usual paleodemographic distribution, one Bayesian estimation based on uniform prior probabilities yielded a population with 57% of the ages at death over 65, while another based on a high mortality life table still had 12% of the individuals aged over 75 years. The seriation method yielded an age distribution more similar to that known from preindustrial historical situations, without excessive longevity of adults. Paleodemography must still wrestle with its elusive goal of accurate adult age estimation from skeletons, a necessary base for demographic study of past populations. KEY WORDS skeletal adult age estimation; bayesian estimation; auricular surface seriation

Variation in the size of structures within mature cortical bone is relevant to our understanding of apparent differences between human samples, and it is relevant to the development of histologically based age-estimation methods. It was proposed that variation may reflect effects of physical activity, through biomechanical and/or metabolic mechanisms. If these factors are local, femoral osteon area (On.Ar) should be more histologically variable than On.Ar in ribs. Ribs should show a higher variation in Haversian canal area (H.Ar) if they are sites of more remodeling activity and hence of arrested refilling of secondary osteons at time of death. This study compares On.Ar and H.Ar of secondary osteons from femora (15) and ribs (29) from 44 Holocene (Later Stone Age) foragers from South Africa (M = 19, F = 25) to values from paired femora and ribs from historic samples (Spitalfields and St. Thomas, 20 pairs from each). Fixed-effects analysis of variance demonstrates rib On.Ar to be significantly smaller than femur, but with no sex or age effects. The femur-to-rib On.Ar ratio is lower for the Holocene foragers than for the two modern samples because of relatively large rib On.Ar. Femora and ribs from the same skeleton normally show femoral On.Ar larger than rib On.Ar (37/44 pairs). Mean femoral values of On.Ar are more diverse than rib On.Ar values, but within-sample coefficients of variation are similar. Values for H.Ar are highly variable and do not reflect anatomical site, age, sex, or population effects. The patterning of osteon size does not appear to be linked to physical activity or to different rates of metabolic activity within the skeleton, at least not in a straightforward way. KEY WORDS bone remodeling; histomorphology; adult age estimation

Otolith-based age estimates for Greenland halibut (Reinhardtius hippoglossoides) have low precision, and there is general uncertainty about their accuracy in older fish (Anon. (1); Alpoim et al. (2)). Low precision [...]

New Re-Os dates obtained from black shales overlying the Sturtian and Areyonga glacial deposits in southern and central Australia, respectively, challenge the prevailing consensus of three Neoproterozoic glaciations. The end of Sturtian glaciation in the Adelaide Rift Complex is constrained by a Re-Os date of 643.0 [+ or -] 2.4 Ma from the overlying Tindelpina Shale Member (basal Tapley Hill Formation). A Re-Os date of 657.2 [+ or -] 5.4 Ma for the basal Aralka Formation constrains the age of the underlying Areyonga glacial deposits in the Amadeus Basin. The Re-Os ages show that the Sturtian and Areyonga glacial deposits are younger than other radiometrically dated (ca. 685-750 Ma) Neoproterozoic glacial intervals previously regarded as possible correlatives. Thus, the 'Sturtian' ice age was markedly diachronous, and/or there was more than one 'Sturtian'-type glaciation. Some Neoproterozoic glacial deposits may represent the products of regional and diachronous glaciation associated with protracted breakup of the supercontinent Rodinia rather than 'snowball' or 'slushball' Earth ice ages. Keywords: Neoproterozoic, age determination, Australia, black shale, rhenium, osmium.

An increasing number of statistical problems arise in connection with functional calibration. In each case, inexpensive indirect data in a particular context are combined with direct expensive-to-acquire data from different but related settings to estimate quantities in the former case. Sometimes (e.g., in chemometrics problems where spectroscopic calibration is used) the indirect data are functional. But more commonly, they are scalar or vector-valued, and the functional component is the quantity that we wish to estimate. The problem treated here is of the latter type. We observe data that give us access to the distribution of U given V, and from these and data on U, we wish to estimate the density of V. The motivating real datasets are of age and covariate information in fish populations. We suggest two methodologies, each of which is based on transforming the problem to one involving inversion of a symmetric linear operator. Our techniques have connections to methods for functional data analysis and for a variety of mixture and deconvolution problems, as well as to calibration techniques. KEY WORDS: Calibration; Deconvolution; Density estimation; Functional data analysis; Ill-posed problem; Kernel methods; Mixture model; Principal components; Regularization; Smoothing.

A new method for estimating skeletal age at death from the morphology of the auricular surface of the ilium is presented. It uses a multiple regression analysis with dummy variables, and is based on the examination of 700 modern Japanese skeletal remains with age records. The observer using this method needs only to check for the presence or absence of nine (for a male) or seven (for a female) features on the auricular surface and to select the parameter estimates of each feature, calculated by multiple regression analysis with dummy variables. The observer can obtain an estimated age from the sum of parameter estimates. It is shown that a fine granular texture of the auricular surface is typical of younger individuals, whereas a heavily porous texture is characteristic of older individuals, and that both of these features are very useful for estimating age. Our method is shown here to be more accurate than other methods, especially in the older age ranges. Since the auricular surface allows more expedient observations than other parts of the skeleton, this new method can be expected to improve the overall accuracy of estimating skeletal age at death. KEY WORDS modern Japanese; multiple regression analysis; dummy variables; binary classification

The microstructure, shape and appearance of the growth rings in statoliths of Nassarius reticulatus (L.) were investigated. This species possesses two statocysts, each containing a single spherical statolith of calcium carbonate of up to 0.22 mm in diameter in the largest animals. The relationship between statolith diameter (SD) and total shell height (TSH) is exponential [ln(TSH)=26.3SD-0.842], although the function is site specific. Statoliths of the largest whelks (>29 mm) contained three or four clearly defined rings, corresponding to TSH values of ~1.1, 4.6-C5.3, 12.0-C13.5 and 18.5 mm, respectively. The first ring likely represents the 'metamorphic' ring that was deposited at the time of larval metamorphosis when the post-larval whelk adopted a benthic lifestyle. The estimated size of the whelks at formation of the second, third and fourth statolith rings closely matched the TSH inferred from the shell rings. It is concluded that the patterns of growth rings present in statoliths can provide information about the age and growth of N. reticulates., Introduction Rings observed on fish otoliths, bones and scales and on bivalve and gastropod shells have, during the past 30-40 years, been widely used for age estimation and growth analysis [...]

Two social factors that could influence age differences in blame attributions were examined: relationship outcome ambiguity (ROA) and personal identification with the characters. ROA is the degree of uncertainty as to the successful resolution of a relationship dilemma. Blame attributions were examined individually for primary and secondary characters in the vignettes. Individuals read vignettes that varied in level of relationship outcome ambiguity. Participants rated the degree to which they blamed and they identified with each character. At high levels of ROA, age differences emerged in that older adults blamed primary characters more than younger adults did. At low levels of ROA, personal identification was the more robust predictor of blaming tendencies. In vignettes high in ROA, salvaging a relationship may take precedence over self-concerns, especially for older adults.

Indirect estimates of instantaneous natural mortality rate (M) are widely used in stock assessment and fisheries management. They are essentially a form of meta-analysis, in which prior information on M [...]

Abstract--Growth parameters were estimated for porbeagle shark (Lamna nasus) in the northwest Atlantic Ocean on the basis of vertebral annuli. A total of 578 vertebrae was analyzed. Annuli were validated [...]

The accuracy and precision of tooth wear for aging gray wolves is evaluated.

Ages of Montana ungulates determined by eruption-wear criteria were often overestimated for younger animals and underestimated for older animals. Ages determined by eruption-wear criteria did not give an accurate estimate of age structure and relative cohort significance for population modelling.

An experiment was conducted to evaluate the effectiveness of the otolith structure found in the King George whitings in Australia in fish age and population research. Three criteria were considered in relating otolith growth to fish age. Results revealed that very thick otoliths hindered the transmittance of light and limited the observation of the internal zonal structure. Opaque zones of the fish sagittae were formed during spring which supported the results of the marginal increment analysis. Otolith count was interpreted based on time of otolith-zone formation and fish's life history.

Researchers investigated the accuracy of estimating sea otter age by counting the number of layers of cementum in their teeth. This practice has been employed in a number of pieces of research but the technique has not been validated. The researchers asked three readers to estimate the ages of 20 sea otters and compared the results with the known ages. The researchers found that the readers used different criteria to interpret the layers. The three readers produced estimates of mean ages of 4.4, 5.9 and 7 years, compared to the actual mean age of 5.1 years.

Hoof growth accurately and reliably predicts neonatal age of white-tailed deer. Linear regression representing hoof growth describes 87% of variations and classifies 74% of the fawns within 3 days of age. The hoof growth model has the minimum squared deviation between actual and predicted ages. All morphometric measures except tail, hindfoot, and head length are low among fawns with low protein-fed dams. Primary body measures are associated with fawn age. Body mass, chest girth, and total length are influenced by maternal protein.

A study has been conducted to evaluate the aging techniques used for waterfowls and to compare the performance of aging birds by using discriminant functions and a posteriori clustering methods. The results revealed that all aging methods may be effective if the appropriate feather variables are used. A posteriori clustering was more effective in measuring large populations than discriminant functions because it avoids errors caused by biased estimators.

We used linear discriminant analysis to test the ability of commonly collected antler characteristics to discriminate ages in an isolated elk population. A discriminant model was developed using three sets of prior classification probabilities; (1) equal among all age-classes, (2) proportional to the sample used to construct the model and (3) mimicking hunter selection bias in Michigan. Antler characteristics were an imprecise predictor of age in harvested bull elk regardless of prior classification probabilities, with overall successful classification rates of 53-67%. Despite popular beliefs, antler characteristics are poor indicators of bull elk ages, even in a small, geographically isolated population such as Michigan's.