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This guide to scoring crown and root traits in human dentitions substantially builds on a seminal 1991 work by Turner, Nichol, and Scott. It provides detailed descriptions and multiple illustrations of each crown and root trait to help guide researchers to make consistent observations on trait expression, greatly reducing observer error. The book also reflects exciting new developments driven by technology that have significant ramifications for dental anthropology, particularly the recent development of a web-based application that computes the probability that an individual belongs to a particular genogeographic grouping based on combinations of crown and root traits; as such, the utility of these variables is expanded to forensic anthropology. This book is ideal for researchers and graduate students in the fields of dental, physical, and forensic anthropology and will serve as a methodological guide for many years to come.

While the study of dental wear has enjoyed wide popularity for over 100 years, dental chipping, or microfractures of the tooth crown, has received little attention. Observations on dental chipping in populations from the Arctic (St. Lawrence Island, Alaska) and Europe (medieval Norway and Spain) reveal patterns of microtrauma that provide insights into the dietary and tooth-tool use behaviour of earlier populations. St. Lawrence Island Inuit, with an emphasis on consuming tough and frozen foods, in combination with extensive tooth-tool use, exhibit a pattern of chipping that is characterised as 'molar dominant'. The two European samples exhibit an 'incisor-dominant' pattern but contrast markedly in frequencies, with medieval Norwegians showing significantly more chipping than medieval and post-medieval Spanish. The systematic study of chipping promises to provide a new perspective on how populations used and/or abused their dentitions in earlier times.

SignificanceThe frequency of the human-specific EDAR V370A isoform is highly elevated in North and East Asian populations. The gene is known to have several pleiotropic effects, among which are sweat gland density and ductal branching in the mammary gland. The former has led some geneticists to argue that the near-fixation of this allele was caused by selection for modulation of thermoregulatory sweating. We provide an alternative hypothesis, that selection instead acted on the allele’s effect of increasing ductal branching in the mammary gland, thereby amplifying the transfer of critical nutrients to infants via mother’s milk. This is likely to have occurred during the Last Glacial Maximum when a human population was genetically isolated in the high-latitude environment of the Beringia.

Until recently, the settlement of the Americas seemed largely divorced from the out-of-Africa dispersal of anatomically modern humans, which began at least 50,000 years ago. Native Americans were thought to represent a small subset of the Eurasian population that migrated to the Western Hemisphere less than 15,000 years ago. Archeological discoveries since 2000 reveal, however, that Homo sapiens occupied the high-latitude region between Northeast Asia and northwest North America (that is, Beringia) before 30,000 years ago and the Last Glacial Maximum (LGM). The settlement of Beringia now appears to have been part of modern human dispersal in northern Eurasia. A 2007 model, the Beringian Standstill Hypothesis, which is based on analysis of mitochondrial DNA (mtDNA) in living people, derives Native Americans from a population that occupied Beringia during the LGM. The model suggests a parallel between ancestral Native Americans and modern human populations that retreated to refugia in other parts of the world during the arid LGM. It is supported by evidence of comparatively mild climates and rich biota in south-central Beringia at this time (30,000-15,000 years ago). These and other developments suggest that the settlement of the Americas may be integrated with the global dispersal of modern humans.

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Summary In order to assess the reliability and repeatability of transthoracic echocardiography for detecting serial changes in cardiac function in horses, day to day variability of a number of echocardiographic indices of ventricular function were studied. The variables investigated were, from 2‐dimensional (2‐D) and M‐mode echocardiography ‐ aortic diameter in systole (AoS), pulmonary artery diameter in systole (PaS), left ventricular internal diameter in systole (LLVIDS) and diastole (LLVIDd), and left ventricular fractional shortening (%FS) and estimated ejection fraction (EF). From pulsed Doppler echocardiography ‐ maximum velocity (Vmax) and acceleration (dv/dtmax) of aortic and pulmonary arterial blood flow, left and right ventricular velocity time integral (AoVTI and PAVTI) and estimated cardiac output (COLV, and CORV), left and right ventricular ejection time (LVET and RVET) and pre‐ejection period (LVPEP and RVPEP), and heart rate. Maximum velocity of early rapid right ventricular filling (ETV) and late right ventricular filling due to right atrial contraction (ATV) were measured. Maximum deceleration and time for deceleration of early rapid filling (dv/dtTV and dtTV) were also determined. Seven healthy mature Thoroughbred horses weighing 490–600 kg were studied. The horses' management regimes and environment were standardised and an echocardiographic examination was carried out on each horse at the same time every day for 6 consecutive days. Two statistical measures of repeatability were calculated for each variable: the intraclass correlation coefficient (rI) and the 95% confidence intervals for error free value of a single measurement. In general, the dimensions and indices of cardiac function derived from 2‐D and M‐mode echocardiography showed better repeatability for individual horses than did the indices derived from Doppler echocardiography. Overall the 95% confidence intervals for an error‐free value of all variables derived from Doppler echocardiography were wide. This must be appreciated when attributing serial measured changes of Doppler echocardiographic variables in an individual animal to effects of a treatment or disease.