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Objectives To examine the correlation between spheno-occipital synchondrosis fusion stages and the hand-wrist skeletal maturity index. Materials and Methods Digital records of 164 individuals (77 males, 87 females) aged 10 to 18 years old were examined. Three-dimensional CBCT scans and hand-wrist two-dimensional radiographs were scored for the spheno-occipital synchondrosis fusion stages and hand-wrist skeletal maturity index, respectively. Statistical analyses were performed for associations using R software with a significance threshold of P< .01. Results A significant positive relationship was demonstrated between spheno-occipital synchondrosis fusion stages and hand-wrist skeletal maturity in both sexes. The Kendall's rank correlation τ between hand-wrist skeletal maturity index and spheno-occipital synchondrosis fusion percentage were high and positive in males and females (r = .74 and r = .71, respectively). Conclusions The significant, positive relationship between the hand-wrist skeletal maturity index and spheno-occipital synchondrosis fusion stages support the idea of using spheno-occipital synchondrosis fusion as a biological indicator for craniofacial and mandibular growth spurt prediction.

Body and canine size dimorphism in fossils inform sociobehavioral hypotheses on human evolution and have been of interest since Darwin's famous reflections on the subject. Here, we assemble a large dataset of fossil canines of the human clade, including all available Ardipithecus ramidus fossils recovered from the Middle Awash and Gona research areas in Ethiopia, and systematically examine canine dimorphism through evolutionary time. In particular, we apply a Bayesian probabilistic method that reduces bias when estimating weak and moderate levels of dimorphism. Our results show that Ar. ramidus canine dimorphism was significantly weaker than in the bonobo, the least dimorphic and behaviorally least aggressive among extant great apes. Average male-to-female size ratios of the canine in Ar. ramidus are estimated as 1.06 and 1.13 in the upper and lower canines, respectively, within modern human population ranges of variation. The slightly greater magnitude of canine size dimorphism in the lower than in the upper canines of Ar. ramidus appears to be shared with early Australopithecus, suggesting that male canine reduction was initially more advanced in the behaviorally important upper canine. The available fossil evidence suggests a drastic size reduction of the male canine prior to Ar. ramidus and the earliest known members of the human clade, with little change in canine dimorphism levels thereafter. This evolutionary pattern indicates a profound behavioral shift associated with comparatively weak levels of male aggression early in human evolution, a pattern that was subsequently shared by Australopithecus and Homo.

Body and canine size dimorphism in fossils inform sociobehavioral hypotheses on human evolution and have been of interest since Darwin’s famous reflections on the subject. Here, we assemble a large dataset of fossil canines of the human clade, including all available Ardipithecus ramidus fossils recovered from the Middle Awash and Gona research areas in Ethiopia, and systematically examine canine dimorphism through evolutionary time. In particular, we apply a Bayesian probabilistic method that reduces bias when estimating weak and moderate levels of dimorphism. Our results show that Ar. ramidus canine dimorphism was significantly weaker than in the bonobo, the least dimorphic and behaviorally least aggressive among extant great apes. Average male-to-female size ratios of the canine in Ar. ramidus are estimated as 1.06 and 1.13 in the upper and lower canines, respectively, within modern human population ranges of variation. The slightly greater magnitude of canine size dimorphism in the lower than in the upper canines of Ar. ramidus appears to be shared with early Australopithecus, suggesting that male canine reduction was initially more advanced in the behaviorally important upper canine. The available fossil evidence suggests a drastic size reduction of the male canine prior to Ar. ramidus and the earliest known members of the human clade, with little change in canine dimorphism levels thereafter. This evolutionary pattern indicates a profound behavioral shift associated with comparatively weak levels of male aggression early in human evolution, a pattern that was subsequently shared by Australopithecus and Homo.

Although stone tools generally co-occur with early members of the genus Homo, they are rarely found in direct association with hominins. We report that both Acheulian and Oldowan artifacts and Homo erectus crania were found in close association at 1.26 million years (Ma) ago at Busidima North (BSN12), and ca. 1.6 to 1.5 Ma ago at Dana Aoule North (DAN5) archaeological sites at Gona, Afar, Ethiopia. The BSN12 partial cranium is robust and large, while the DAN5 cranium is smaller and more gracile, suggesting that H. erectus was probably a sexually dimorphic species. The evidence from Gona shows behavioral diversity and flexibility with a lengthy and concurrent use of both stone technologies by H. erectus, confounding a simple "single species/single technology" view of early Homo.

Among living mammals, only the African apes and some anteaters adopt knuckle-walking as their primary locomotor behavior. That Pan and Gorilla both knuckle-walk has been cited as evidence of their common ancestry and a primitive condition for a combined Homo, Pan, and Gorilla clade. Recent research on forelimb ontogeny and anatomy, in addition to recently described hominin fossils, indicate that knuckle-walking was independently acquired after divergence of the Pan and Gorilla lineages. Although the large-bodied, largely suspensory orangutan shares some aspects of the African ape bauplan, it does not regularly knuckle-walk when terrestrial. While many anatomical correlates of knuckle-walking have been identified, a functional explanation of this unusual locomotor pattern has yet to be proposed. Here, we argue that it was adopted by African apes as a means of ameliorating the consequences of repetitive impact loadings on the soft and hard tissues of the forelimb by employing isometric and/or eccentric contraction of antebrachial musculature during terrestrial locomotion. Evidence of this adaptation can be found in the differential size and fiber geometry of the forearm musculature, and differences in torso shape between the knuckle-walking and non-knuckle-walking apes (including humans). We also argue that some osteological features of the carpus and metacarpus that have been identified as adaptations to knuckle-walking are consequences of cartilage remodeling during ontogeny rather than traits limiting motion in the hand and wrist. An understanding of the functional basis of knuckle-walking provides an explanation of the locomotor parallelisms in modern Pan and Gorilla. Anat Rec, 301:496-514, 2018. © 2018 Wiley Periodicals, Inc.

Runners frequently experience pain in the hip, pelvis, and thigh. The differential diagnosis is broad, and pain in these regions often presents a diagnostic and therapeutic challenge. Common conditions include muscle strain, proximal hamstring tendinopathy, greater trochanteric pain syndrome, snapping hip syndrome, iliopsoas bursitis/tendonitis, and femoroacetabular impingement. A detailed understanding of potential etiologies as well as performing a detailed history and physical examination is critical to establish a diagnosis and to initiate appropriate treatment. Physical therapy and running gait analysis with retraining are essential in treating hip, pelvic, and thigh pain in the runner. More high-quality and runner-specific research is needed to determine optimal treatments.

Background Several sacroiliac joint (SIJ) provocative tests used to assess posterior pelvic pain involve moving and stressing the hip. It is unknown if there is a subgroup of patients with posterior pelvic pain who have underlying hip deformity that could potentially influence performance and interpretation of these tests. Objective To describe the prevalence of radiographic hip deformity and hip osteoarthritis in a group of adults 40 years old and under who met the clinical diagnostic criteria for treatment of posterior pelvic pain with an image guided intra-articular SIJ injection. Design Retrospective cohort study. Setting Tertiary university orthopedic department PATIENTS (OR PARTICIPANTS): One hundred and forty-eight patients were evaluated (83% (123/148) female; mean age 31.3 ± 6.2 years). All had completed a trial of comprehensive noninvasive treatment for posterior pelvic pain and had a minimum of three positive SIJ provocative tests on physical examination. Methods Retrospective review identified patients undergoing SIJ injection for pain recommended and performed by seven physiatrists between 2011 and 2017. Hip radiographs were read by a physician with expertise in hip measurements with previously demonstrated excellent intrarater reliability. Main outcome measurements Percentage of patients with hip deformity findings. Results No patients meeting the inclusion criteria had significant radiographic hip osteoarthritis (Tonnis ≥2 indicating moderate or greater radiographic hip osteoarthritis) and 4/148 (3%) were found to have mild radiographic hip osteoarthritis. Prearthritic hip disorders were identified in 123 (83%, 95% CI: 76, 89%) patients. For those patients with prearthritic hip disorders, measurements consistent with femoroacetabular impingement (FAI) were seen in 61 (41%) patients, acetabular dysplasia in 49 (33%) patients, and acetabular retroversion in 85 (57%) patients. Acetabular retroversion was identified in 43% (crossover sign) and 39% (prominent ischial spine) of patients. Conclusions Approximately 57% of adult patients under the age of 40 years with the clinical symptom complex of SIJ pain were found to have radiographic acetabular retroversion. This is a higher percentage than the 5%-15% found in asymptomatic people in the current literature. Further study is needed to assess links between hip structure, hip motion, and links to pelvic pain including peri and intra-articular SIJ pain. Level of evidence III.

Previously, we described several features of the carpometacarpal joints in extant large-bodied apes that are likely adaptations to the functional demands of vertical climbing and suspension. We observed that all hominids, including modern humans and the 4.4-million-year-old hominid Ardipithecus ramidus, lacked these features. Here, we assess the uniqueness of these features in a large sample of monkey, ape, and human hands. These new data provide additional insights into the functional adaptations and evolution of the anthropoid hand. Our survey highlights a series of anatomical adaptations that restrict motion between the second and third metacarpals (MC2 and MC3) and their associated carpals in extant apes, achieved via joint reorganization and novel energy dissipation mechanisms. Their hamate-MC4 and -MC5 joint surface morphologies suggest limited mobility, at least in Pan. Gibbons and spider monkeys have several characters (angled MC3, complex capitate-MC3 joint topography, variably present capitate-MC3 ligaments) that suggest functional convergence in response to suspensory locomotion. Baboons have carpometacarpal morphology suggesting flexion/extension at these joints beyond that observed in most other Old World monkeys, probably as an energy dissipating mechanism minimizing collision forces during terrestrial locomotion. All hominids lack these specializations of the extant great apes, suggesting that vertical climbing was never a central feature of our ancestral locomotor repertoire. Furthermore, the reinforced carpometacarpus of vertically climbing African apes was likely appropriated for knuckle-walking in concert with other novel potential energy dissipating mechanisms. The most parsimonious explanation of the structural similarity of these carpometacarpal specializations in great apes is that they evolved independently.

The Early Pliocene Sagantole Fm. in the Gona Project area, Afar State, Ethiopia, is noted for discoveries of the early hominin Ardipithecus ramidus. A large series of fossil cercopithecid primates dated to between 4.8 and 4.3 Ma has also been collected from these sediments. In this paper, we use qualitative analysis and standard dental and postcranial measures to systematically describe the craniodental remains and tentatively allocate postcrania to taxa where we are able to. We then use these data to compare these specimens to fossil assemblages from contemporary sites, interpret their paleobiology, and discuss implications for the paleoecology of the Gona Sagantole Fm. We recognize three cercopithecid species in the Gona Sagantole Fm. Pliopapio alemui makes up approximately two-thirds of the identifiable specimens; nearly all of the rest are allocated to Kuseracolobus aramisi, and a single molar indicates the presence of a second, somewhat larger but morphologically distinct papionin. Among the Early Pliocene cercopithecids from Gona are also a number of postcranial elements. None of the postcranial remains are directly associated with any of the cranial material. Nonetheless, some of the distal humeri and proximal femora can be tentatively allocated to either Pl. alemui or K. aramisi based on a combination of size, as the latter is approximately 50% larger than the former, and morphology. If these assignments are correct, they suggest K. aramisi was primarily arboreal and similar to most extant colobines, whereas Pl. alemui was more mixed in its substrate use, being more terrestrially adapted than K. aramisi, but less so than extant Papio or Theropithecus. Thus, we interpret the predominance of Pl. alemui over K. aramisi is consistent with a somewhat more open environment at Gona than at Aramis.

Homo erectus was anatomically variable and behaviorally flexible using both Oldowan and Acheulian artifacts., Although stone tools generally co-occur with early members of the genus Homo, they are rarely found in direct association with hominins. We report that both Acheulian and Oldowan artifacts and Homo erectus crania were found in close association at 1.26 million years (Ma) ago at Busidima North (BSN12), and ca. 1.6 to 1.5 Ma ago at Dana Aoule North (DAN5) archaeological sites at Gona, Afar, Ethiopia. The BSN12 partial cranium is robust and large, while the DAN5 cranium is smaller and more gracile, suggesting that H. erectus was probably a sexually dimorphic species. The evidence from Gona shows behavioral diversity and flexibility with a lengthy and concurrent use of both stone technologies by H. erectus, confounding a simple “single species/single technology” view of early Homo.

Objective To determine the prevalence of stress fractures, menstrual dysfunction and disordered eating attitudes in elite female soccer athletes. Design Cross-sectional descriptive study. Setting Female soccer athletes were recruited from a national level youth soccer club, an NCAA Division I university team, and a women's professional team. Participants Two hundred twenty female soccer athletes with a mean age of 16.4 ± 4 years and BMI of 20.8 ± 2 kg/m 2 completed the study, representing all athletes from the included teams. Methods One-time surveys completed by the athletes. Main Outcome Measurements Height and weight were recorded, and body mass index (BMI) was calculated for each athlete. Athletes reported age of menarche, history of missing 3 or more menses within a 12-month period and stress fracture. The Eating Attitudes Test (EAT-26) was used to assess the athlete's body perception and attitudes toward eating. Results Of the 220 soccer athletes, 3 athletes (1.6%) had a low BMI for their age, and 19 (8.6%) reported stress fractures of the lower extremity. Among athletes who had reached menarche, the average onset was 13 + 1 year; menstrual dysfunction were present in 21 (19.3%). On the EAT-26, 1 player scored in the high risk range (>20) and 17 (7.7%) scored in the intermediate risk range (10-19) for eating disorders. Athletes with an EAT-26 score ≥ 10 points had a significantly higher prevalence of menstrual dysfunction in the past year compared to athletes with an EAT-26 score of less than 10 ( P = .02). Conclusions Elite female soccer athletes are susceptible to stress fractures and menstrual dysfunction and have delayed onset of menarche despite normal BMI and appropriate body perception and attitudes towards eating. Further studies are needed to better understand stress fracture risk in female soccer athletes and in other team sports to determine how these findings relate to long-term bone health in this population.

This study examines the relationship between spheno-occipital synchondrosis (SOS) closure and puberty onset in a modern American population. It also investigates the timing and the rate of SOS closure in males and females.The sample includes cross-sectional and longitudinal 3D Cone Beam Computed Tomography (CBCT) scans of 741 individuals (361 males and 380 females) aged 6-20 years. Each CBCT scan is visualized in the mid-sagittal plane, and the spheno-occipital synchondrosis (SOS) is scored as completely open, partially fused, mostly fused, and completely fused. The Menarche commencement is used as an indicator of puberty onset in females.Mean ages of open, partially-fused, mostly-fused, and completely fused SOS were 11.07, 12.95, 14.44, and 16.41 years in males, and 9.75, 11.67, 13.25, and 15.25 in females, respectively. The results show there is a significant association between the SOS closure stage and the commencement of menarche (Fisher's Exact Test p0.001). It was found that females had a higher SOS closure rate (38.60%) per year than males at the age of 10 years. The closure rate in males appears slower than females at age 10, but it lasts a longer time, ranging between 22 and 26% per year from age 11 to 14 years.There is a significant relationship between puberty onset and SOS closure, suggesting its closure is at least partially affected by systemic, hormonal changes in the growing adolescent. Also, SOS closure occurs at a faster rate and at an earlier age in females compared to males.

Ancient terrestrial ecosystems cannot be observed directly, but a wide variety of approaches and techniques have been developed that provide indirect evidence of many aspects of ecosystem functioning. By integrating multiple lines of evidence about the climate, vegetational structure, and fauna of a given location at a particular time, a relatively complete paleoecological picture of a fossil locality can be generated. This volume reviews some of the most commonly used techniques for paleobiological and paleoecological analysis; in this chapter, we briefly introduce these approaches and the insights they can provide. They include techniques for: inferring attributes of particular mammal species and/or individuals (body mass, locomotor adaptations, diet, life history variables); interpreting ancient soils (paleosols), trace fossils (ichnofossils), organic biomolecules, and plant remains of various types (pollen, phytoliths, macrofossils); analyzing isotopic and geometric morphometric data to answer a range of ecological and environmental questions; and seeking patterns in data across broad taxonomic, geographic, and/or temporal scales (ecomorphology, ecometrics, and ecological diversity analysis).

Functional analyses of the 4.4 Ma hominin Ardipithecus ramidus postcrania revealed a previously unknown and unpredicted locomotor pattern combining arboreal clambering and a form of terrestrial bipedality. To date, all of the fossil evidence of Ar. ramidus locomotion has been collected from the Aramis area of the Middle Awash Research Project in Ethiopia. Here, we present the results of an analysis of additional early Pliocene Ar. ramidus fossils from the Gona Project study area, Ethiopia, that includes a fragmentary but informative partial skeleton (GWM67/P2) and additional isolated manual remains. While we reinforce the original functional interpretations of Ar. ramidus of having a mixed locomotor adaptation of terrestrial bipedality and arboreal clambering, we broaden our understanding of the nature of its locomotor pattern by documenting better the function of the hip, ankle, and foot. The newly recovered fossils document a greater adaptation to bipedality in the Ar. ramidus ankle and hallux than previously recognized. In addition, a newly discovered scaphoid bone with a fusing os centrale provides further evidence about the nature of hominin hand evolution.

Background In young and middle-aged adults with and without hip deformity, hip pain receives treatment focused primarily related to hip structure. Because this hip pain may be chronic, these patients develop other coexisting, modifiable disorders related to pain that may go undiagnosed in this young and active population, including insomnia and anxiety. Objective The objective of this study was to compare assessments of insomnia and anxiety in young and middle-aged adults presenting with hip pain with no greater than minimal osteoarthritis (OA) compared to asymptomatic healthy controls. Comparisons between types of hip deformity and no hip deformity in hip pain patients were performed to assess whether patients with specific hip deformities were likely to have insomnia or anxiety as a cofounding disorder to their hip pain. Design Prospective case series with control comparison. Setting Two tertiary university physiatry outpatient clinics. Participants A total of 50 hip pain patients aged 18-40 years and 50 gender- and age-matched healthy controls. Methods Patients were enrolled if 2 provocative hip tests were found on physical examination and hip radiographs had no or minimal OA. Radiographic hip deformity measurements were completed by an independent examiner. Comparisons of insomnia and anxiety were completed between 50 hip pain patients and 50 controls and between patients with different types of hip deformity. Main Outcome Measures Insomnia Severity Index (ISI) and Pain Anxiety Symptoms Scale (PASS). Results A total of 50 hip pain patients (11 male and 39 female) with mean age of 31.2 ± 8.31 years enrolled. Hip pain patients slept significantly less ( P = .001) per night than controls. Patients experienced significantly greater insomnia ( P = .0001) and anxiety ( P = .0001) compared to controls. No differences were found in insomnia and anxiety scores between hip pain patients with and without hip deformity or between different types of hip deformity. Conclusion Hip pain patients with radiographs demonstrating minimal to no hip arthritis with and without hip deformity experience significant cofounding yet modifiable disorders of sleep and anxiety. If recognized early in presentation, treatment of insomnia and anxiety ultimately will improve outcomes for hip patients treated either conservatively or surgically for their hip disorder. Level of Evidence II

Eurygnathohippus is a genus of hipparionine horse that evolved in and was confined to the African continent from the late Miocene to Pleistocene interval. Eurygnathohippus woldegabrieli is a new species from Aramis, Ethiopia, dated between 4.4 and 4.2 Ma. The hypodigm is currently restricted to 157 specimens from 14 Aramis localities and one nearby Gona locality. We nominate a mandible as the type and a maxillary dentition and two complete metacarpal IIIs as paratypes. Our analysis reveals that Eurygnathohippus woldegabrieli is derived compared with late Miocene Eurygnathohippus feibeli in its overall size, cheek tooth crown height, mandibular symphysis length, and robusticity of distal limb elements. It is primitive in mandibular symphysis length and robusticity of distal limb elements compared with the more advanced medial Pliocene species Eurygnathohippus hasumense. A study of Eurygnathohippus woldegabrieli's paleodiet as measured by two mesowear methods, corroborated by carbon isotope studies...

Kolpochoerus (Mammalia: Suidae) is a suine genus represented by a number of species from Plio-Pleistocene sites in Africa. While the general trends in Kolpochoerus evolution are broadly known, gaps in the fossil record preclude an understanding of the details of its evolutionary tempo and mode. Here, we describe a new species, Kolpochoerus millensis, based on new fossil material from the Woranso-Mille and Gona sites in the Central Afar region of Ethiopia and dated to 3.5–3.8 million years ago (Ma). Third molars of K. millensis are metrically and morphologically intermediate between the early Pliocene K. deheinzelini and earliest late Pliocene K. afarensis. It appears that K. deheinzelini, K. millensis, and K. afarensis are temporally disjunct and phenetically distinguishable parts of a single evolving lineage. The recognition of these chronospecies provides additional evidence for anagenetic evolution. It demonstrates clearly the presence of transitional forms in the fossil record. The extensive and well-dated Kolpochoerus fossil record serves as one of the best documented examples of the occurrence of phyletic evolution. Moreover, K. millensis is one of the best biochronological markers in eastern Africa for the time between 3.5 and 3.8 Ma.

The Middle Awash Ardipithecus ramidus sample comprises over 145 teeth, including associated maxillary and mandibular sets. These help reveal the earliest stages of human evolution. Ar. ramidus lacks the postcanine megadontia of Australopithecus . Its molars have thinner enamel and are functionally less durable than those of Australopithecus but lack the derived Pan pattern of thin occlusal enamel associated with ripe-fruit frugivory. The Ar. ramidus dental morphology and wear pattern are consistent with a partially terrestrial, omnivorous/frugivorous niche. Analyses show that the ARA-VP-6/500 skeleton is female and that Ar. ramidus was nearly monomorphic in canine size and shape. The canine/lower third premolar complex indicates a reduction of canine size and honing capacity early in hominid evolution, possibly driven by selection targeted on the male upper canine.

Genomic comparisons have established the chimpanzee and bonobo as our closest living relatives. However, the intricacies of gene regulation and expression caution against the use of these extant apes in deducing the anatomical structure of the last common ancestor that we shared with them. Evidence for this structure must therefore be sought from the fossil record. Until now, that record has provided few relevant data because available fossils were too recent or too incomplete. Evidence from Ardipithecus ramidus now suggests that the last common ancestor lacked the hand, foot, pelvic, vertebral, and limb structures and proportions specialized for suspension, vertical climbing, and knuckle-walking among extant African apes. If this hypothesis is correct, each extant African ape genus must have independently acquired these specializations from more generalized ancestors who still practiced careful arboreal climbing and bridging. African apes and hominids acquired advanced orthogrady in parallel. Hominoid spinal invagination is an embryogenetic mechanism that reoriented the shoulder girdle more laterally. It was unaccompanied by substantial lumbar spine abbreviation, an adaptation restricted to vertical climbing and/or suspension. The specialized locomotor anatomies and behaviors of chimpanzees and gorillas therefore constitute poor models for the origin and evolution of human bipedality.

Spontaneous vertebral fractures are a common occurrence in modern humans, yet these fractures are not documented in other hominoids. Differences in vertebral bone strength between humans and apes associated with trabecular bone microarchitecture may contribute to differences in fracture incidence. We used microcomputed tomography to examine trabecular bone microarchitecture in the T8 vertebra of extant young adult hominoids. Scaled volumes of interest from the anterior vertebral body were analyzed at a resolution of 46 microm, and bone volume fraction, trabecular thickness, trabecular number, trabecular separation, structure model index, and degree of anisotropy were compared among species. As body mass increased, so did trabecular thickness, but bone volume fraction, structure model index, and degree of anisotropy were independent of body mass. Bone volume fraction was not significantly different between the species. Degree of anisotropy was not significantly different among the species, suggesting similarity of loading patterns in the T8 vertebra due to similar anatomical and postural relationships within each species' spine. Degree of anisotropy was negatively correlated with bone volume fraction (r(2) = 0.85, P < 0.05) in humans, whereas the apes demonstrated no such relationship. This suggested that less dense human trabecular bone was more preferentially aligned to habitual loading. Furthermore, we theorize that trabeculae in ape thoracic vertebrae would not be expected to become preferentially aligned if bone volume fraction was decreased. The differing relationship between bone volume fraction and degree of anisotropy in humans and apes may cause less dense human bone to be more fragile than less dense ape bone.

Background Papillary breast lesions comprise a spectrum of histopathologic diagnoses ranging from benign papillomas to papillary carcinomas. There is ongoing controversy regarding the management of papillary lesions diagnosed by core needle biopsy (CNB). Some authors advocate observation of papillary lesions when the CNB is benign, while others recommend surgical excision of all papillary lesions. The current study assessed the adequacy of CNB in evaluating papillary breast lesions. Methods A search of the pathology database at our institution identified 122 papillary lesions diagnosed by CNB. The study population consisted of 71 papillary lesions that were subsequently surgically excised. Results Of the 71 papillary lesions excised, 8 were malignant, 16 were atypical, and 47 were benign at the time of CNB. Of the 47 papillary lesions thought to be benign, 13 (28%) revealed atypia and 4 (9%) revealed malignancy upon surgical excision. Of the 13 atypical papillary lesions on CNB, 7 lesions (54%) were associated with malignancy upon excision. Slightly over half the upgrades were due to finding atypia or malignancy in the tissue surrounding the papillary lesion. The total rate of upgrades from the CNB diagnosis to the excisional diagnosis was 38%. Conclusions When a core biopsy of a papillary lesion is encountered, there is a strong likelihood of discovering atypia or malignancy in the index lesion or in close proximity. Therefore, surgical excision should be performed to avoid missing a malignancy and to allow for accurate breast cancer risk assessment that can impact survival and decisions regarding chemoprevention.

The discovery of 4.5-million-year-old fossils of the hominid Ardipithecus ramidus increases our knowledge of a fascinating stage of human evolution, before hominids left the forests for the open savanna. Fossil finds of this age are rare, but deposits in Gona, Ethiopia, have yielded material from at least nine individuals. Their context shows that they lived in an environment of moderate rainfall woodland, and grasslands. Comparative biomolecular studies suggest that the last common ancestor of humans and chimpanzees, our closest living relatives, lived during the Late Miocene–Early Pliocene1,2. Fossil evidence of Late Miocene–Early Pliocene hominid evolution is rare and limited to a few sites in Ethiopia3,4,5, Kenya6 and Chad7. Here we report new Early Pliocene hominid discoveries and their palaeoenvironmental context from the fossiliferous deposits of As Duma, Gona Western Margin (GWM), Afar, Ethiopia. The hominid dental anatomy (occlusal enamel thickness, absolute and relative size of the first and second lower molar crowns, and premolar crown and radicular anatomy) indicates attribution to Ardipithecus ramidus. The combined radioisotopic and palaeomagnetic data suggest an age of between 4.51 and 4.32 million years for the hominid finds at As Duma. Diverse sources of data (sedimentology, faunal composition, ecomorphological variables and stable carbon isotopic evidence from the palaeosols and fossil tooth enamel) indicate that the Early Pliocene As Duma sediments sample a moderate rainfall woodland and woodland/grassland.

Fluvio-lacustrine sediments of the Hadar and Busidima Formations along the northern Awash River (Ethiopia) archive almost three million years (3.4 to

A 4.5 Ma record of fluvial and lacustrine deposits is well exposed at Gona, in the Afar Depression of Ethiopia. We use isotopic values of pedogenic carbonate and fossil teeth to reconstruct Plio–Pleistocene environmental change at Gona. An increase in δ13C values of pedogenic carbonates since 4.5 Ma points to a shift from woodlands to grassy woodlands in the early Pliocene, −10.4 to −3.9‰ (VPDB), to more open but still mixed environments in the late Pleistocene, −3.0 to −1.4‰ (VPDB). This pattern is also seen in isotopic records elsewhere in East Africa. However, at 1.5 Ma the higher proportion of C4 grasses at Gona is largely a result of a local facies shift to more water-limited environments. The wide range of δ13C values of pedogenic carbonate within single stratigraphic levels indicates a mosaic of vegetation for all time intervals at Gona that depends on depositional environment. Elements of this mosaic are reflected in δ13C values of both modern plants and soil organic matter and Plio–Pleistocene soil carbonate, indicating higher amounts of C4 grasses with greater distance from a river channel in both the modern and ancient Awash River systems. δ18O values of pedogenic carbonates increase up-section from −11.9‰ in the early Pliocene to −6.4‰ (VPDB) in the late Pleistocene. The wide range of δ18O values in paleovertisol carbonates from all stratigraphic levels probably reflects short-term climate changes and periods of strong evaporation throughout the record. Based on the comparison between δ18O values of Plio–Pleistocene pedogenic carbonates and modern waters, we estimate that there has been a 6.5‰ increase in mean annual δ18O values of meteoric water since 4.5 Ma. δ18O values of pedogenic carbonate from other East African records indicate a similar shift. Increasing aridity and fluctuations in the timing and source of rainfall are likely responsible for the changes in δ18O values of East African pedogenic carbonates through the Plio–Pleistocene.

CRAFT Research Center, 419 N. Indiana Avenue, Indiana University, Bloomington, IN, 47405, USA Department of Anthropology, Southern Connecticut State University, 501 Crescent Street, New Haven, CT 06515-1355, USA Department of Geosciences, University of Arizona, Tucson, AZ, 85721, USA Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, USA Department of Earth and Planetary Science, University of California, Berkeley, CA 94709, USA Departmento de Prehistoria y Arquelogia, Facultad de Geografia, e Historia, Universidad Complutense de Madrid, Ciudad Universitaria 28040, Madrid, Spain Department of Anthropology and CRAFT Research Center, 419 N. Indiana Avenue, Indiana University, Bloomington, IN, 47405, USA Sterkfontein Research Unit, University of Witwatersrand, WITS 2050, Johannesburg, South Africa Department of Anatomy, Case Western Reserve University-School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106-4930, USA Laboratory of Physical Anthropology, Cleveland Museum of Natural History, Cleveland, OH 44106, USA

Objectives This study examines the relationship between spheno-occipital synchondrosis (SOS) closure and puberty onset in a modern American population. It also investigates the timing and the rate of SOS closure in males and females. Materials and methods The sample includes cross-sectional and longitudinal 3D Cone Beam Computed Tomography (CBCT) scans of 741 individuals (361 males and 380 females) aged 6–20 years. Each CBCT scan is visualized in the mid-sagittal plane, and the spheno-occipital synchondrosis (SOS) is scored as completely open, partially fused, mostly fused, and completely fused. The Menarche commencement is used as an indicator of puberty onset in females. Results Mean ages of open, partially-fused, mostly-fused, and completely fused SOS were 11.07, 12.95, 14.44, and 16.41 years in males, and 9.75, 11.67, 13.25, and 15.25 in females, respectively. The results show there is a significant association between the SOS closure stage and the commencement of menarche (Fisher's Exact Test p < 0.001). It was found that females had a higher SOS closure rate (38.60%) per year than males at the age of 10 years. The closure rate in males appears slower than females at age 10, but it lasts a longer time, ranging between 22 and 26% per year from age 11 to 14 years. Conclusion There is a significant relationship between puberty onset and SOS closure, suggesting its closure is at least partially affected by systemic, hormonal changes in the growing adolescent. Also, SOS closure occurs at a faster rate and at an earlier age in females compared to males.

Among living mammals, only the African apes and some anteaters adopt knuckle-walking as their primary locomotor behavior. That Pan and Gorilla both knuckle-walk has been cited as evidence of their common ancestry and a primitive condition for a combined Homo, Pan, and Gorilla clade. Recent research on forelimb ontogeny and anatomy, in addition to recently described hominin fossils, indicate that knuckle-walking was independently acquired after divergence of the Pan and Gorilla lineages. Although the large-bodied, largely suspensory orangutan shares some aspects of the African ape bauplan, it does not regularly knuckle-walk when terrestrial. While many anatomical correlates of knuckle-walking have been identified, a functional explanation of this unusual locomotor pattern has yet to be proposed. Here, we argue that it was adopted by African apes as a means of ameliorating the consequences of repetitive impact loadings on the soft and hard tissues of the forelimb by employing isometric and/or eccentric contraction of antebrachial musculature during terrestrial locomotion. Evidence of this adaptation can be found in the differential size and fiber geometry of the forearm musculature, and differences in torso shape between the knuckle-walking and non-knuckle-walking apes (including humans). We also argue that some osteological features of the carpus and metacarpus that have been identified as adaptations to knuckle-walking are consequences of cartilage remodeling during ontogeny rather than traits limiting motion in the hand and wrist. An understanding of the functional basis of knuckle-walking provides an explanation of the locomotor parallelisms in modern Pan and Gorilla. Anat Rec, 301:496-514, 2018. © 2018 Wiley Periodicals, Inc.

Previously, we described several features of the carpometacarpal joints in extant large-bodied apes that are likely adaptations to the functional demands of vertical climbing and suspension. We observed that all hominids, including modern humans and the 4.4-million-year-old hominid Ardipithecus ramidus, lacked these features. Here, we assess the uniqueness of these features in a large sample of monkey, ape, and human hands. These new data provide additional insights into the functional adaptations and evolution of the anthropoid hand. Our survey highlights a series of anatomical adaptations that restrict motion between the second and third metacarpals (MC2 and MC3) and their associated carpals in extant apes, achieved via joint reorganization and novel energy dissipation mechanisms. Their hamate-MC4 and -MC5 joint surface morphologies suggest limited mobility, at least in Pan. Gibbons and spider monkeys have several characters (angled MC3, complex capitate-MC3 joint topography, variably present capitate-MC3 ligaments) that suggest functional convergence in response to suspensory locomotion. Baboons have carpometacarpal morphology suggesting flexion/extension at these joints beyond that observed in most other Old World monkeys, probably as an energy dissipating mechanism minimizing collision forces during terrestrial locomotion. All hominids lack these specializations of the extant great apes, suggesting that vertical climbing was never a central feature of our ancestral locomotor repertoire. Furthermore, the reinforced carpometacarpus of vertically climbing African apes was likely appropriated for knuckle-walking in concert with other novel potential energy dissipating mechanisms. The most parsimonious explanation of the structural similarity of these carpometacarpal specializations in great apes is that they evolved independently.

The arrival of Europeans in the New World had profound and long-lasting results for the native peoples. The record for the impact of this fundamental change in culture, society, and biology of Native Americans is well documented historically. This paper reviews the biological impact of the arrival of Europeans on native populations via the study of pre- and postcontact skeletal remains in Spanish Florida, the region today represented by coastal Georgia and northern Florida. The postcontact skeletal series, mostly drawn from Roman Catholic mission sites, are among the most comprehensive in the Americas, providing a compelling picture of adaptation and stress in this setting. Study of paleopathology, dental and skeletal indicators of physiological stress, stable isotope (carbon and nitrogen) analysis, tooth microwear, and skeletal morphology (cross-sectional geometry) reveals major alterations in quality of life and lifestyle. The bioarchaeological record indicates a general deterioration in health, declining dietary diversity and nutritional quality, and increasing workload in the contact period. The impact of contact in Spanish Florida appears to have been more dramatic in comparison with other regions, which likely reflects the different nature of contact relations in this setting versus other areas (e.g., New England, New France). The bioarchaeological record represents an important information source for understanding the dynamics of biocultural change resulting from colonization and conquest.

The Maka locality in Ethiopia's Middle Awash area has yielded new craniodental remains dated to 3.4 million years (myr) in age. These remains are described and assessed functionally and systematically. The fossils are assigned to Australopithecus afarensis. Maka thus joins Hadar and Laetoli as the third major locality yielding this species. As with previous site samples, the Maka collection displays a wide range of size variation. The nearly complete and undistorted MAK-VP-1/12 adult mandible from Maka is an excellent match for Hadar and Laetoli counterparts, confirming the geographic and temporal distribution of A. afarensis. This specimen shows that this taxon is functionally and developmentally hominid in its incisor/canine/premolar complex. A postulated evolutionary trajectory through A. anamensis to A. afarensis would have involved postcanine megadontia and other adaptations to a more heavily masticated diet relative to the earlier Ardipithecus ramidus. Am J Phys Anthropol 111:45–68, 2000. © 2000 Wiley-Liss, Inc.

Human first ribs demonstrate predictable, sequential changes in shape, size, and texture with increasing age, and thus, can be used as an indicator of age at death. Metamorphosis of the first rib's head, tubercle, and costal face was documented in a cross-sectional sample of preadult and adult first ribs of known age at death from the Hamann-Todd skeletal collection (Cleveland Museum of Natural History, Cleveland, Ohio). Blind tests of the usefulness of the first rib as an age indicator were conducted, including tabulation of intraobserver and interobserver inaccuracies and biases. First rib age estimates show inaccuracies and biases by decade comparable to those generated by other aging techniques. Indeed, the first rib method is useful as an isolated age indicator. When used in conjunction with other age indicators, the first rib improves the quality of summary age assessments.

The lack of an adequate hominid fossil record in eastern Africa between 2 and 3 million years ago (Ma) has hampered investigations of early hominid phylogeny. Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus . This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo . Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm–to–lower arm ratio.

The differences in limb lengths and proportions between humans and chimpanzees are widely known. Humans have relatively shorter forelimbs and longer hind limbs than chimpanzees. Humans have a longer period of long bone formation than chimpanzees. Recent advances in estimating age-at-death in chimpanzees from their dentition have allowed us to reexamine long bone growth in chimpanzees using their skeletal remains and compare it with similar data for humans. A chronological normalization procedure allowing direct interspecific comparison of long bone growth is presented. The preadult chimpanzee sample (n = 43) is from the Hamann-Todd Osteological Collection from the Cleveland Museum of Natural History. All human specimens (n = 202) are from the late Woodland Libben Population currently housed at Kent State University. Relying on these cross-sectional data, we conclude that both species elongate their femora at similar absolute (length per unit time) but different relative (length relative to normalized dental age) rates. The species differ in the absolute growth rate of the humerus but share a common normalized rate of growth. Forelimb segment proportion differences between species are due to differential elongation rates of the segments. Hind limb diaphyseal proportions are the same in both species, which suggests that changes in segment length are proportional. Therefore, alternative developmental mechanisms exist in these closely related species which can produce changes in limb length.

The sternal surface of the 4th rib has been suggested as a useful predictor of adult age-at-death (Iscan et al.: Journal of Forensic Sciences 29:1094-1104, 1984; American Journal of Physical Anthropology 65:147-156, 1984). We tested its ability to do so in two tests. In the first, we developed a method of seriation and target age assignment for the 4th rib so that inaccuracy and bias of the method could be assessed by decade. We found that the 4th rib shows characteristic changes in morphology with age and can be included in multifactorial age estimates. In the second test, we applied the phase method developed by Iscan et al. (Journal of Forensic Sciences 29:1094-1104, 1984). The results of our three judges were generally similar to those reported by Iscan and Loth (Journal of Forensic Sciences 31:122-132, 1986). Measures of race differences in 4th rib morphology were included in both tests. Americans of African descent (black) showed a non-significant trend for the rib changes to be delayed compared to Americans of European descent (white). This is in contrast to the work of Iscan et al., which predicted that blacks would show a tendency toward accelerated rib changes compared to whites, especially after the early 30s (phases 5-7) (Iscan et al.: Journal of Forensic Sciences 32(2):452-466, 1987).

New data on hominoid dental development are presented. Individual bivariate pairings of all mandibular teeth were made for African apes and humans. Data were analyzed with a full linear regression model. No statistically significant differences were found among apes, although a consis- tent pattern of earlier incisal development was observed in Pan relative to Gorilla. This is concordant with an earlier fusion of the premaxil1ary:maxil- lary suture in Pan. Only one tooth pair differed significantly by sex among apes. Two biologically distinct human samples (Libben and Hamann-Todd), although assessed differently (extraction and radiography) yielded virtually identical results. Humans differ from apes only by earlier relative calcification of their anterior teeth. This can be viewed as a consequence of reduced facial prognathism and a shift in hominid canine function. That relative dental development (espe- cially of the cheek teeth) directly reflects prolongation of somatic maturation in homi- nids has become a long-standing, widely held view (Mann, 1975; Gould, 1977; Smith, 1986, 1989; Dean and Wood, 1981; Dean, 1987, 1989). Although the timing of human dental development is relatively well known (Nolla, 1960; Moorrees et al., 1963; Fanning, 1961; Anderson et al., 19761, our knowledge of ape dental development is restricted to a few early reports (Schultz, 1935; Nissen and Rie- sen, 1964; Willoughby, 1978) which were based on very limited samples. A more exten- sive study of pongid development was con- ducted by Dean and Wood (1981) for the expressed purpose of establishing an arche- typical developmental schedule for pongids. A primary consequence of the methods em- ployed to achieve this goal was a requisite suppression of variation within the samples used. Therefore, these same data cannot be used to accurately judge the taxonomic or developmental affinity of additional speci- mens. Thus, the use of these standards to identify the developmental pattern of indi- vidual fossils is inappropriate (contra Smith, 1986). In an effort to resolve these issues, we recently presented a comparison of the rela- tive rates of maturation of the permanent teeth in modern humans and the African apes (Simpson

Genomic comparisons have established the chimpanzee and bonobo as our closest living relatives. However, the intricacies of gene regulation and expression caution against the use of these extant apes in deducing the anatomical structure of the last common ancestor that we shared with them. Evidence for this structure must therefore be sought from the fossil record. Until now, that record has provided few relevant data because available fossils were too recent or too incomplete. Evidence from Ardipithecus ramidus now suggests that the last common ancestor lacked the hand, foot, pelvic, vertebral, and limb structures and proportions specialized for suspension, vertical climbing, and knuckle-walking among extant African apes. If this hypothesis is correct, each extant African ape genus must have independently acquired these specializations from more generalized ancestors who still practiced careful arboreal climbing and bridging. African apes and hominids acquired advanced orthogrady in parallel. Hominoid spinal invagination is an embryogenetic mechanism that reoriented the shoulder girdle more laterally. It was unaccompanied by substantial lumbar spine abbreviation, an adaptation restricted to vertical climbing and/or suspension. The specialized locomotor anatomies and behaviors of chimpanzees and gorillas therefore constitute poor models for the origin and evolution of human bipedality.

The Middle Awash Ardipithecus ramidus sample comprises over 145 teeth, including associated maxillary and mandibular sets. These help reveal the earliest stages of human evolution. Ar. ramidus lacks the postcanine megadontia of Australopithecus. Its molars have thinner enamel and are functionally less durable than those of Australopithecus but lack the derived Pan pattern of thin occlusal enamel associated with ripe-fruit frugivory. The Ar. ramidus dental morphology and wear pattern are consistent with a partially terrestrial, omnivorous/frugivorous niche. Analyses show that the ARA-VP-6/500 skeleton is female and that Ar. ramidus was nearly monomorphic in canine size and shape. The canine/lower third premolar complex indicates a reduction of canine size and honing capacity early in hominid evolution, possibly driven by selection targeted on the male upper canine.