Tremendous progress has been made since cementum analysis first applications in the 1950s. Today, with a better understanding of cementum biology, robust, replicable protocols support promising innovative research. Now, cementum should be considered within a broader evolutionary framework and cementogenesis tested from chronobiology theoretical assumptions to identify genetic or environmental variables affecting its circannual growth. With the rise of image analysis automation and optimization of species-specific standardized protocols, cementochronology is mature for site-level experiments. Also, the groundbreaking evolution of noninvasive, 3D cementochronology opens opportunities to study the fossil record, from stem-mammals to our Homo lineage. The breadth of applications across disciplines is a testament to cementochronology as a unique tool to investigate age and season at death, mobility patterns, life-history events, or mammalian evolutionwhich should be deployed broadly in anthropology. The goal of this volume is to promote collaborative efforts and stimulate interdisciplinary opportunities to renew diverse anthropology themes using cementum in anthropology.

The purpose of this volume is to gather interdisciplinary scholars to explore and implement cementochronology, the analysis of cementum growth, from a chronobiology perspective. Chronobiology, the study of biological rhythms, rests on the premise that the regular rotation of the earth around its central axis and the sun produces two fundamental periodicities to which all life has become adapted. The evolutionary "clock-shop" model posits that circadian clocks govern daily rhythmicity, and circannual clocks provide a seasonal endogenous calendar. We present current theories explaining and interpreting cyclic growth marks observed in hard tissues, especially cementum. Repeated empirical and validation studies are now available to explain cementum's annual/seasonal periodicity, even though specific molecular pathways are still needed. We present our evidence in three parts covering cementum biology, protocols, and anthropological applications and argue that cementochronology with its regular and continuous growth characteristics should have a privileged place among skeletal age indicators.

Paleodemographic mortality profiles are flawed due in part to well-understood methodological problems with individual age-at-death estimates. Cementochronology combined with probability density analysis potentially provides a solution. In this chapter we apply cementochronology as a single age indicator to reconstruct the mortality profile and life table of an archaeological sample of deciduous and permanent teeth from 119 individuals in France. Our results are consistent with the parish register data and demonstrate that cementochronology is effective in estimating the mortality of those under the age of 35. However, the method appears to underestimate the age-at-death for elderly individuals. This research points to the need for additional testing in elderly subjects. In addition, to improve the representativeness of archaeological samples, expanding this approach to other types of teeth for adults and subadults remains a major issue.

The activities’ spatial organization of Neanderthal’s territory is often explored by studying stone tool production and use, and its economy, but not their hunting behavior. Consequently, the hypothesis that Neanderthals lacked planning potential or complex land-use strategies during the Mousterian, such as collaborative hunting and food storage, has been questioned. A cementochronology analysis of reindeer in Quina and Discoidal Denticulate in four neanderthal sites in southwestern France suggests a repeated use of specific sites at a precise time of the year for similar hunting purposes scheduled according to a year-round pattern. The development of landmark sites during the late Middle Paleolithic used every year, at the same moment, indicates that the predation system began to structure the activity’s organization within the territory in time and space and that the preys’ behavior directly impacted the social organization of the hunting groups.

Accurate age-at-death estimates are essential for inferring health, identity, diversity, and demography within archaeological skeletal samples. Unfortunately, the macroscopic skeletal structures may be compromised by dysplastic, endocrine, and circulatory disorders. Cementochronology provides a reliable alternative approach for evaluating acellular cementum banding. Using cementochronology, we present an age-at-death estimate for a pre-Columbian, adult female with a combined skeletal dysplasia, achondroplasia and Leri-Weill dyschondrosteosis. Cementochronology has re-defined the age-at-death estimate between 30 to 34 years. These results not only assist in developing a more accurate age-at-death estimation and biological profile, but they also facilitate creating nuanced interpretations for a physically challenged, pregnant female in her Middle Woodland social context. Further, this analysis emphasizes the utility of cementochronology in estimating age-at-death of skeletal individuals with pathological conditions that compromise commonly used macroscopic methods and encourages researchers to consider this technique in paleodemography, paleoepidemiology, and forensic anthropology.

The evolution of nomadic collectors' fertility and mortality before the agriculture invention in independent centers 10,000 years ago is still debated. Skeletal samples are the only way to observe prehistoric demographic patterns directly. Each assemblage is critical for direct investigation since pre-farming groups exhibit high residential mobility. Cabeçuda is a funerary mound (sambaqui) in Santa Catarina State, Brazil. Its occupation (4,180BP-1,800BP) corresponds to its expansion peak and decline with horticulturalists' arrival. A cementochronology analysis of 93 skeletons suggests a high frequency of young adults and a lack of adults past 60, which departs from contemporary collector models but is common in catastrophic samples or migratory events. The metabolic load model predicts that a group of semi-nomadic fisher-gatherers should display transitional fertility between sedentary farmers and nomadic collectors. This is the case for Cabeçuda with a 15P5 ratio below and a TFR within all contemporary pre-farming groups. However, within a quasi-stable hypothesis, several variables can produce the same output, and we lack the data to evaluate the death structure.

In recent years, the Tooth Cementum Annulations method has been demonstrated to be highly effective at estimating age at death in permanent teeth. Prior to this study, no validation studies have attempted to use TCA to age deciduous teeth. Deciduous teeth provide unique challenges for anthropologists seeking to use the TCA method. Among these are the constraint that cementum annulations are only countable immediately before and after the root apex closes, and the fact that in healthy teeth the cementum record is destined to be destroyed by rhizolysis, so cementum annulations will only be available in teeth that are surgically extracted, or in teeth from juvenile decedents. From a practical standpoint, we found that methods that had previously yielded good results in permanent teeth worked much less well in deciduous teeth. The use of high magnification, bright-field illumination, and analyzing multiple regions of interest per tooth are all recommended for best results.

Age-at-death mortality profiles provide an important supplementary record of mortality risks that archaeological populations faced. We use hazard modeling to calculate the risk of death by age for adults to establish a mortality profile for the Petra North Ridge sample. Age-at-death estimates were generated using cementochronology from 66 individuals, which not only provides more accurate age estimates but increases our sample size due to the fragmented and commingled nature of the Petra assemblage. Our results indicate that the mortality profile from Petra resembles that of an attritional sample. The regional and local political-economic, physical and social environments resulted in age-specific mortality risks lower than that typically expected for an ancient, urban population and potentially reflected immigration of young adults into Petra.