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In the last 300 thousand years, the genus Chlorocebus expanded from equatorial Africa into the southernmost latitudes of the continent, where colder climate was a probable driver of natural selection. We investigated population-level genetic variation in the mitochondrial uncoupling protein 1 (UCP1) gene region—implicated in non-shivering thermogenesis (NST)—in 73 wild savannah monkeys from three taxa representing this southern expansion (Chlorocebus pygerythrus hilgerti, Chlorocebus cynosuros and Chlorocebus pygerythrus pygerythrus) ranging from Kenya to South Africa. We found 17 single nucleotide polymorphisms with extended haplotype homozygosity consistent with positive selective sweeps, 10 of which show no significant linkage disequilibrium with each other. Phylogenetic generalized least-squares modelling with ecological covariates suggest that most derived allele frequencies are significantly associated with solar irradiance and winter precipitation, rather than overall low temperatures. This selection and association with irradiance is demonstrated by a relatively isolated population in the southern coastal belt of South Africa. We suggest that sunbathing behaviours common to savannah monkeys, in combination with the strength of solar irradiance, may mediate adaptations to thermal stress via NST among savannah monkeys. The variants we discovered all lie in non-coding regions, some with previously documented regulatory functions, calling for further validation and research. [ABSTRACT FROM AUTHOR]

Vervet monkeys ( Chlorocebus aethiops) exhibit bright blue scrotal skin which may function to mediate social interactions by acting as a socio-sexual signal. Previous research on scrotal coloration among vervet monkeys was limited to experimental work on captive Ch. a. sabaeus, the least colorful vervet subspecies, and two field studies of the more colorful Ch. a. pygerythrus. In a study of free-ranging and captive vervet monkeys in South Africa ( Ch. pygerythrus), West Africa ( Ch. a. sabaeus) and the Caribbean ( Ch. a. sabaeus), we examined scrotal color variation across geographically distant subspecies. We provide an exploration of how digital photographs may be used to quantify and analyze blue and green skin coloration by examining the blue-yellow opponency channel and luminance channel as color measures. We found that that at all ages the scrotal color of Ch. a. pygerythrus males was always bluer and darker than that of Ch. a. sabaeus males. Among Ch. a. pygerythrus scrotal color becomes bluer and lightens with increasing age, while the color of Ch. a. sabaeus males also lightens, but becomes less blue with increasing age. We suggest that color variation is related to maturation and may function as an age-related signal among Ch. a. pygerythrus and Ch. a. sabaeus. We also found color was related to three morphological features among adults. For Ch. a. pygerythrus, higher body weight is associated with more blue color and longer canine length is associated with lighter color. Lighter color was associated with longer body lengths among Ch. a. sabaeus. Future studies focused on color variation within age classes are needed to examine the potential signal content of color in this species. Am. J. Primatol. 75:752-762, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In the last 300 thousand years, the genus Chlorocebus expanded from equatorial Africa into the southernmost latitudes of the continent, where colder climate was a probable driver of natural selection. We investigated population-level genetic variation in the mitochondrial uncoupling protein 1 ( UCP1 ) gene region-implicated in non-shivering thermogenesis (NST)-in 73 wild savannah monkeys from three taxa representing this southern expansion ( Chlorocebus pygerythrus hilgerti, Chlorocebus cynosuros and Chlorocebus pygerythrus pygerythrus ) ranging from Kenya to South Africa. We found 17 single nucleotide polymorphisms with extended haplotype homozygosity consistent with positive selective sweeps, 10 of which show no significant linkage disequilibrium with each other. Phylogenetic generalized least-squares modelling with ecological covariates suggest that most derived allele frequencies are significantly associated with solar irradiance and winter precipitation, rather than overall low temperatures. This selection and association with irradiance is demonstrated by a relatively isolated population in the southern coastal belt of South Africa. We suggest that sunbathing behaviours common to savannah monkeys, in combination with the strength of solar irradiance, may mediate adaptations to thermal stress via NST among savannah monkeys. The variants we discovered all lie in non-coding regions, some with previously documented regulatory functions, calling for further validation and research.

Objective: Vervet monkeys are common in most tree-rich areas of South Africa, but their absence from grassland and semi-desert areas of the country suggest potentially restricted and mosaic local population patterns that may have relevance to local phenotype patterns and selection. A portion of the mitochondrial DNA control region was sequenced to study patterns of genetic differentiation., Methods: DNA was extracted, and mitochondrial DNA sequences were obtained from 101 vervet monkeys at 15 localities, which represent both an extensive (widely across the distribution range) and intensive (more than one troop at most of the localities) sampling strategy. Analyses utilized Arlequin 3.1, MEGA 6, BEAST v1.5.2, and Network V3.6.1., Results: The dataset contained 26 distinct haplotypes, with six populations fixed for single haplotypes. Pairwise P-distance among population pairs showed significant differentiation among most population pairs, but with nonsignificant differences among populations within some regions. Populations were grouped into three broad clusters in a maximum likelihood phylogenetic tree and a haplotype network. These clusters correspond to i) north-western, northern, and north-eastern parts of the distribution range as well as the northern coastal belt; ii) central areas of the country; and iii) southern part of the Indian Ocean coastal belt and adjacent inland areas., Conclusions: Apparent patterns of genetic structure correspond to current and past distribution of suitable habitat, geographic barriers to gene flow, geographic distance, and female philopatry. However, further work on nuclear markers and other genomic data are necessary to confirm these results., (© 2015 Wiley Periodicals, Inc.)

Objective: Determine the effect of raloxifene or estrogen, as compared with placebo, on the reporting of urinary incontinence in postmenopausal women participating in an osteoporosis prevention trial., Design: The current analysis is based on adverse event data that were collected as part of a double-blind, randomized, placebo-controlled trial designed to assess the efficacy and safety of raloxifene for osteoporosis prevention in postmenopausal women. Women were 40 to 60 years of age at study entry and had a prior hysterectomy. A total of 619 women were randomized to placebo, raloxifene 60 or 150 mg/d, or conjugated equine estrogen 0.625 mg/d and followed for up to 3 years. Urinary incontinence was self-reported and rated by participants as "mild," "moderate," or "severe.", Results: The prevalence of urinary incontinence as reported by patients at baseline was similar across treatment groups (3% to 6%, P = 0.46). During 3 years of follow-up, new or worsening urinary incontinence was reported with the following frequency: placebo (1.3%), raloxifene 60 mg/d (0.7%), raloxifene 150 mg/d (0.6%), and conjugated equine estrogen (7.0%). The percentage of estrogen subjects reporting urinary incontinence was significantly greater than that for placebo and both doses of raloxifene (P < or = 0.02)., Conclusion: During 3 years of follow-up, conjugated equine estrogen was associated with an increased incidence of reports of urinary incontinence in women with a prior hysterectomy and this was significantly greater than both placebo and raloxifene.