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Theropithecus was a common large-bodied primate that co-occurred with hominins in many Plio-Pleistocene deposits in East and South Africa. Stable isotope analyses of tooth enamel from T. brumpti (4.0-2.5 Ma) and T. oswaldi (2.0-1.0 Ma) in Kenya show that the earliest Theropithecus at 4 Ma had a diet dominated by C4 resources. Progressively, this genus increased the proportion of C4-derived resources in its diet and by 1.0 Ma, had a diet that was nearly 100% C4-derived. It is likely that this diet was comprised of grasses or sedges; stable isotopes cannot, by themselves, give an indication of the relative importance of leaves, seeds, or underground storage organs to the diet of this primate. Theropithecus throughout the 4- to 1-Ma time range has a diet that is more C4-based than contemporaneous hominins of the genera Australopithecus, Kenyanthropus, and Homo; however, Theropithecus and Paranthropus have similar proportions of C4-based resources in their respective diets. [ABSTRACT FROM AUTHOR]

Abstract: Investigations of the well-known paleontological and archaeological site of Tangzigou in western Yunnan Province in 2003 and 2006 yielded plentiful mammalian remains and a large number of stone and bone artifacts. Among the mammalian remains were those of many micromammals representing modern taxa of Scandentia, Insectivora, and Rodentia. The micromammal assemblage is dominated by rodents, which constitute 92% of the total number of identifiable elements. Murids are the most common elements, followed by rhizomyids, sciurids, and hystricids. The Tangzigou deposits appear to have been created over a period of 200–300 years in the early to middle Holocene, judging from the tight cluster of AMS radiocarbon dates between 9000 and 8745 BP. Based on the known habitat preferences of the living species, most of the Tangzigou micromammals were arboreal or dwellers of the forest floor. The micromammal assemblage thus indicates that subtropical forest including bamboo dominated the environment around Tangzigou. The assemblage is remarkable for the near absence of very small micromammal species such as small mice. This bias appears to have been introduced by humans who collected the larger-bodied species of micromammals for food. This interpretation is supported by the presence of a large number of burned elements, especially dentaries. The analysis of the larger mammals also showed that Tangzigou was a place where prehistoric people gathered to butcher the hunted/scavenged animals. [Copyright &y& Elsevier]

Human skin pigmentation evolved as a compromise between the conflicting physiological demands of protection against the deleterious effects of ultraviolet radiation (UVR) and photosynthesis of UVB-dependent vitamin D3. Living under high UVR near the equator, ancestral Homo sapiens had skin rich in protective eumelanin. Dispersals outside of the tropics were associated with positive selection for depigmentation to maximize cutaneous biosynthesis of pre-vitamin D3 under low and highly seasonal UVB conditions. In recent centuries, migrations and high-speed transportation have brought many people into UVR regimes different from those experienced by their ancestors and, accordingly, exposed them to new disease risks. These have been increased by urbanization and changes in diet and lifestyle. Three examples—nutritional rickets, multiple sclerosis (MS) and cutaneous malignant melanoma (CMM)—are chosen to illustrate the serious health effects of mismatches between skin pigmentation and UVR. The aetiology of MS in particular provides insight into complex and contingent interactions of genetic and environmental factors necessary to trigger lethal disease states. Low UVB levels and vitamin D deficiencies produced by changes in location and lifestyle pose some of the most serious disease risks of the twenty-first century. [ABSTRACT FROM AUTHOR]

The article presents an examination into the evolution of human skin pigmentation. The author traces several periods of human evolution surrounding the emergence of Homo erectus and Homo sapiens, noting distinct points where differences in skin color developed as a natural selection response to ultraviolet radiation exposure and vitamin D absorption in varied latitudes. Conclusions are then offered asserting the disassociation of skin color and race.

Human skin pigmentation is the product of two dines produced by natural selection to adjust levels of constitutive pigmentation to levels of UV radiation (UVR). One dine was generated by high UVR near the equator and led to the evolution of dark, photoprotective, eumelanin–rich pigmentation. The other was produced by the requirement for UVB photons to sustain cutaneous photosynthesis of vitamin D3 in low–UVB environments, and resulted in the evolution of depigmented skin. As hominins dispersed outside of the tropics, they experienced different intensities and seasonal mixtures of UVA and UVB. Extreme UVA throughout the year and two equinoctial peaks of UVB prevail within the tropics. Under these conditions, the primary selective pressure was to protect folate by maintaining dark pigmentation. Photolysis of folate and its main se'rum form of 5–methyihydrofolate is caused by UVR and by reactive oxygen species generated by UVA. Competition for folate between the needs for cell division, DNA repair, and melanogenesis is severe under stressful, high–UVR conditions and is exacerbated by dietary insufficiency. Outside of tropical latitudes, UVB levels are generally low and peak only once during the year. The populations exhibiting maximally depigmented skin are those inhabiting environments with the lowest annual and summer peak levels of UVB. Development of facultative pigmentation (tanning) was important to populations settling between roughly 23° and 46° , where levels of UVB varied strongly according to season. Depigmented and tannable skin evolved numerous times in hominin evolution via independent genetic pathways under positive selection. [ABSTRACT FROM AUTHOR]

The original version of this article unfortunately contained mistakes. Table 5 is the comparison of upper and lower molars. However, the published edition only showed the sub-title of the upper molars, and the sub-title of the lower molars are missing. [ABSTRACT FROM AUTHOR]

There are thousands of fossils of hominins, but no fossil chimpanzee has yet been reported. The chimpanzee (Pan) is the closest living relative to humans. Chimpanzee populations today are confined to wooded West and central Africa, whereas most hominin fossil sites occur in the semi-arid East African Rift Valley. This situation has fuelled speculation regarding causes for the divergence of the human and chimpanzee lineages five to eight million years ago. Some investigators have invoked a shift from wooded to savannah vegetation in East Africa, driven by climate change, to explain the apparent separation between chimpanzee and human ancestral populations and the origin of the unique hominin locomotor adaptation, bipedalism. The Rift Valley itself functions as an obstacle to chimpanzee occupation in some scenarios. Here we report the first fossil chimpanzee. These fossils, from the Kapthurin Formation, Kenya, show that representatives of Pan were present in the East African Rift Valley during the Middle Pleistocene, where they were contemporary with an extinct species of Homo. Habitats suitable for both hominins and chimpanzees were clearly present there during this period, and the Rift Valley did not present an impenetrable barrier to chimpanzee occupation. [ABSTRACT FROM AUTHOR]

Humans skin is the most visible aspect of the human phenotype. It is distinguished mainly by its naked appearance, greatly enhanced abilities to dissipate body heat through sweating, and the great range of genetically determined skin colors present within a single species. Many aspects of the evolution of human skin and skin color can be reconstructed using comparative anatomy, physiology, and genomics. Enhancement of thermal sweating was a key innovation in human evolution that allowed maintenance of homeostasis (including constant brain temperature) during sustained physical activity in hot environments. Dark skin evolved pari passu with the loss of body hair and was the original state for the genus Homo. Melanin pigmentation is adaptive and has been maintained by natural selection. Because of its evolutionary lability, skin color phenotype is useless as a unique marker of genetic identity. In recent prehistory, humans became adept at protecting themselves from the environment through clothing and shelter, thus reducing the scope for the action of natural selection on human skin. [ABSTRACT FROM AUTHOR]

Modern hippopotamuses are strongly dependent on permanent water because of the structure and properties of their skin, and because they forage on vegetation located close to watercourses. In the fossil record of Asia, the disappearance of hippopotamids (best represented by Hexaprotodon sivalensis) during the late Neogene and Pleistocene was due to a dramatic increase in seasonal patterns of rainfall and river flow, which would have resulted in many river systems being dry for months of the year. The lack of permanent water resulted in the disappearance of He. sivalensis from Asia. Heightened seasonality of rainfall resulted from an intensification of the winter and summer monsoons during the period between 3.6 and 2.6 Ma. Because of the exquisite sensitivity of hippopotamuses to the availability of permanent water, well-established dates for the last appearance of He. sivalensis in Asian fossil sequences can be used as direct indicators of the onset of highly seasonal patterns of rainfall and river flow. [Copyright &y& Elsevier]

A relatively complete skeleton of the fossil papionin, Theropithecus brumpti, from the site of Lomekwi, west of Lake Turkana, Kenya, is here described. The specimen, KNM-WT 39368, was recovered at the site of LO 5 (3°51′N and 35°45′E), from sediments dated to approximately 3·3 Ma. The skeleton is that of an old adult male and preserves a number of articulated elements, including most of the forelimbs and tail. The cranial morphology is that of a large, early T. brumpti, exhibiting a deep mandible with a deeply excavated mandibular corpus fossa, and mandibular alveoli and cheek teeth arrayed in a reversed Curve of Spee. The forelimb skeleton exhibits a unique mixture of characteristics generally associated with a terrestrial locomotor habitus, such as a narrow scapula and a highly stable elbow joint, combined with those more representative of habitual arborealists, such as muscle attachments reflecting a large rotator cuff musculature and a flexible shoulder joint. The forelimb of KNM-WT 39368 also presents several features, unique toTheropithecus , which represent adaptations for manual grasping and fine manipulation. These features include a large, retroflexed medial humeral epicondyle (to which large pronator, and carpal and digital flexor muscles attached) and proportions of the digital rays that denote capabilities for precise opposition between the thumb and index finger. Taken together, these features indicate that one of the earliest recognized representatives of Theropithecus exhibited the food harvesting and processing anatomy that distinguished the genus through time and that contributed to its success throughout the later Pliocene and Pleistocene. Based on the anatomy of KNM-WT 39368 and the known habitat preference of T. brumpti, the species is reconstructed as being a generally terrestrial but highly dexterous, very large-bodied, sexually dimorphic, and possibly folivorous papionin. T. brumpti was adapted for propulsive quadrupedal locomotion over generally even ground, and yet was highly adept at manual foraging. The estimate of 43·8 kg body mass for KNM-WT 39368 renders unlikely the possibility that the species, or at least adult males of the species, were highly arboreal. T. brumpti, as represented by KNM-WT 39368, is seen as a large, colorfully decorated, and basically terrestrial papionin that was restricted to riverine forest habitats in the Lake Turkana Basin from the middle to latest Pliocene. [Copyright &y& Elsevier]

Gibbons are small arboreal apes that display an accelerated rate of evolutionary chromosomal rearrangement and occupy a key node in the primate phylogeny between Old World monkeys and great apes. Here we present the assembly and analysis of a northern white-cheeked gibbon (Nomascus leucogenys) genome. We describe the propensity for a gibbon-specific retrotransposon (LAVA) to insert into chromosome segregation genes and alter transcription by providing a premature termination site, suggesting a possible molecular mechanism for the genome plasticity of the gibbon lineage. We further show that the gibbon genera (Nomascus, Hylobates, Hoolock and Symphalangus) experienced a near-instantaneous radiation ~5 million years ago, coincident with major geographical changes in Southeast Asia that caused cycles of habitat compression and expansion. Finally, we identify signatures of positive selection in genes important for forelimb development (TBX5) and connective tissues (COL1A1) that may have been involved in the adaptation of gibbons to their arboreal habitat.

Describes an extinct subspecies of the Javan lutung, Trachypithecus auratus sangiranensis, based on an isolated, tooth-bearing upper-jaw. Location where the specimen was found; Morphological similarities of the fossil monkey to the living species of leaf monkey from Java; Etymology.

Assesses feeding and masticatory function in western tarsiers from field study. Videotaped recordings of foraging, feeding behavior and chewing of wild-caught animals in temporary captivity; Dissection of temporomandibular joint and muscles of mastication; Scanning microscopic (SEM) examination of wear features of teeth.

Of the many peculiarities that enable the giant panda (Ailuropoda melanoleuca), a member of the order Carnivora, to adapt to life as a dedicated bamboo feeder, its extra "thumb" is arguably the most celebrated yet enigmatic. In addition to the normal five digits in the hands of most mammals, the giant panda has a greatly enlarged wrist bone, the radial sesamoid, that acts as a sixth digit, an opposable "thumb" for manipulating bamboo. We report the earliest enlarged radial sesamoid, already a functional opposable "thumb," in the ancestral panda Ailurarctos from the late Miocene site of Shuitangba in Yunnan Province, China. However, since the late Miocene, the "thumb" has not enlarged further because it must be balanced with the constraints of weight bearing while walking in a plantigrade posture. This morphological adaptation in panda evolution thus reflects a dual function of the radial sesamoid for both bamboo manipulation and weight distribution. The latter constraint could be the main reason why the panda's false thumb never evolved into a full digit. This crude "thumb" suggests that the origin of the panda's dedicated bamboo diet goes back to as early as 6–7 Ma. [ABSTRACT FROM AUTHOR]

A dentate mandible and proximal femur of Mesopithecus pentelicus Wagner, 1839 are described from the Shuitangba lignite mine in Zhaotong Prefecture, northeastern Yunnan Province, China. The remains were retrieved from sediments just below those that yielded a juvenile Lufengpithecus cranium and are dated at about ∼6.4 Ma. The mandible and proximal femur were found in close proximity and are probably of the same individual. The lower teeth are metrically and morphologically closely comparable with those of confirmed M. pentelicus from Europe, and on this basis, the specimen is assigned to this species. The anatomy of the proximal femur indicates that the Shuitangba Mesopithecus was a semiterrestrial quadruped that engaged in a range of mostly arboreal activities, including walking, climbing, and occasional leaping, with an abducted hip joint. The Shuitangba Mesopithecus is dentally typical for the genus but may have been more arboreal than previously described for M. pentelicus. M. pentelicus is well known from late Miocene (MN 11–12) sites in Europe and southwest Asia. Its estimated average rate of dispersal eastward was relatively slow, although it could have been episodically more rapid. The presence of a colobine, only slightly lower in the same section at Shuitangba that produced Lufengpithecus , is one of the only two well-documented instances of the near or actual co-occurrence of a monkey and ape in the Miocene of Eurasia. At Shuitangba, M. pentelicus occupied a freshwater-margin habitat with beavers, giant otters, swamp rabbits, and many aquatic birds. The presence of M. pentelicus in southwest China near the end of the Miocene further attests to the ecological versatility of a species long recognized as widespread and adaptable. The modern colobines of Asia, some or all of which are probable descendants of Mesopithecus , have gone on to inhabit some of the most highly seasonal and extreme habitats occupied by nonhuman primates. [ABSTRACT FROM AUTHOR]

The author focuses on recommendations by the U.S. Preventive Services Task Force (USPSTF) recommendations about counseling patients in self-management of prevention and early detection of skin cancer. Topics discussed include counseling young adults, adolescents, children, and parents of young children about minimizing exposure to ultraviolet radiation and for patients and clinicians to consider the presence of risk factors for skin cancer.

Introduction: Hyperpigmentation disorders are very frequent, affect the quality of life and may become a psychological burden for afflicted patients. Many anti‐pigmenting or depigmenting agents are available with various efficacy and almost no comparative data. 2‐mercaptonicotinoyl glycine (2‐MNG) was recently proposed as a viable candidate showing safe and effective results on hyperpigmentation control in vitro and in vivo. Objectives: A Bayesian network meta‐analysis (BNMA) was conducted to map and rank the anti‐pigmenting and depigmenting efficacy of 2‐MNG 0.5% on UV daylight (UVDL)‐induced pigmentation together with 13 other reference molecules. A comparison in the kinetics of 2‐MNG 0.5% was also performed. Methodology: Fourteen studies were conducted, for each, on 15–30 women of skin phototype III in Shanghai, China and Paris, France. The products were applied on mini zone, in randomized and blinded protocol, on the back, 5 days a week during 6 weeks, at a dose of 4 mg/cm2. During the second week, volunteers were exposed under to varying minimum erythemal dose of UVDL during 4 consecutive days—adapted to obtain a similar induction of skin pigmentation regardless of the population. Assessments were performed instrumentally using Chromameter®. Ascorbic acid 7% was used as a positive control for all experiments. A Bayesian network meta‐analysis was then established to map and follow the kinetics of 2‐MNG 0.5% performance with 13 reference molecules (glutathione 2%, kojic acid 1%, hydroquinone 4%, ascorbyl glucoside 2%, niacinamide 4%, etc.). Results: 2‐MNG 0.5% dominated the ranking at all time points with a significant high probability of strong efficacy against UVDL‐induced pigmentation. Ascorbic acid 7% ranks second after 4 days of irradiations (D12) whereas hydroquinone 4% ranks second 1 month after irradiations (D40). In the kinetics, 2‐MNG at 0.5% was effective as from the end of irradiations (D12) to the study endpoint (D40). This suggested an immediate and persistent efficacy across all timepoints evaluated. Conclusion: The BNMA revealed a rapid and lasting efficacy of 2‐MNG 0.5% on the anti‐pigmenting and depigmenting phases of the clinical protocol. 2‐MNG 0.5% ranked first, with immediate and lasting effect compared to 13 other references. This study is the first allowing comparison between reference anti‐pigmenting and depigmenting agents and will help clinicians for proposing the most effective approach for their patients. [ABSTRACT FROM AUTHOR]

Objectives: Mildred Trotter was an anatomist and physical anthropologist whose studies on hair morphology, growth, somatic distribution, and trait relationships to age and ethnogeographic population were foundational to the field of microscopical hair analysis. The collection of human hair samples she assembled for her research has been an underutilized resource for studies on human hair variation. We applied updated methods and reviewed Trotter's original data to reassess the relationship hair traits have to diverse population labels. Methods: Hair form and pigmentation patterns were measured from a subset of the hair samples accumulated by Trotter and we compared our data to Trotter's original results. Variability in hair traits were tested within individuals, within populations, and among ethnogeographic groups. Results: Measured hair cross‐section dimensions and melanosome density and distribution revealed substantial variability within individuals and ethnogeographic populations. Hair traits were found to not be distinctly separable by ancestry but instead showed continuous variation across human populations. Trotter's measurements were precise and the dataset she compiled remains valid, though the conclusions should be reviewed in light of our current understanding of human variation. Discussion: Our findings support moving away from categorical ancestry classifications and eliminating the use of outdated racial typologies in favor of more descriptive trait analysis. Detailed analysis of trait pattern distributions are presented that may be useful for future research on human variation. We point to the need for additional research on human variation and hair trait relationships with reference to known population affinity. [ABSTRACT FROM AUTHOR]

Critiques an article which was written by John N. Relethford in 1997, pertaining to the hemispheric difference in human skin color. Relethford's suggestion that human skin was darker in the Southern than in the Northern Hemisphere at equivalent latitude, and suggested that ultraviolet (UV) radiation was a contributing factor; Analysis of erythemally weighted UV exposures at the earth's surface; Findings of the analysis.