Increased ecological resource variability during a critical transition in hominin evolution.

Although climate change is considered to have been a large-scale driver of African human evolution, landscape-scale shifts in ecological resources that may have shaped novel hominin adaptations are rarely investigated. We use well-dated, high-resolution, drill-core datasets to understand ecological dynamics associated with a major adaptive transition in the archeological record ~24 km from the coring site. Outcrops preserve evidence of the replacement of Acheulean by Middle Stone Age (MSA) technological, cognitive, and social innovations between 500 and 300 thousand years (ka) ago, contemporaneous with large-scale taxonomic and adaptive turnover in mammal herbivores. Beginning ~400 ka ago, tectonic, hydrological, and ecological changes combined to disrupt a relatively stable resource base, prompting fluctuations of increasing magnitude in freshwater availability, grassland communities, and woody plant cover. Interaction of these factors offers a resource-oriented hypothesis for the evolutionary success of MSA adaptations, which likely contributed to the ecological flexibility typical of Homo sapiens foragers.

Environmental dynamics during the onset of the Middle Stone Age in eastern Africa.

Development of the African Middle Stone Age (MSA) before 300,000 years ago raises the question of how environmental change influenced the evolution of behaviors characteristic of early Homo sapiens We used temporally well-constrained sedimentological and paleoenvironmental data to investigate environmental dynamics before and after the appearance of the early MSA in the Olorgesailie basin, Kenya. In contrast to the Acheulean archeological record in the same basin, MSA sites are associated with a markedly different faunal community, more pronounced erosion-deposition cycles, tectonic activity, and enhanced wet-dry variability. Aspects of Acheulean technology in this region imply that, as early as 615,000 years ago, greater stone material selectivity and wider resource procurement coincided with an increased pace of land-lake fluctuation, potentially anticipating the adaptability of MSA hominins.

Long-distance stone transport and pigment use in the earliest Middle Stone Age.

Previous research suggests that the complex symbolic, technological, and socioeconomic behaviors that typify Homo sapiens had roots in the middle Pleistocene <200,000 years ago, but data bearing on human behavioral origins are limited. We present a series of excavated Middle Stone Age sites from the Olorgesailie basin, southern Kenya, dating from ≥295,000 to ~320,000 years ago by argon-40/argon-39 and uranium-series methods. Hominins at these sites made prepared cores and points, exploited iron-rich rocks to obtain red pigment, and procured stone tool materials from ≥25- to 50-kilometer distances. Associated fauna suggests a broad resource strategy that included large and small prey. These practices imply notable changes in how individuals and groups related to the landscape and to one another and provide documentation relevant to human social and cognitive evolution.

Do Knowledge and Attitudes Regarding Intrauterine Devices Predict Interest in Their Use?

BACKGROUND: Increasing use of intrauterine devices (IUDs) is seen as a promising strategy to prevent unintended pregnancies, particularly among young women. In this study, we examined correlates of young women's interest in using an IUD, including sources of information about, knowledge of, and attitudes toward IUDs. METHODS: We conducted a national Web survey of young adults (ages 18-29) in 2012. Using a subset of data from 382 sexually experienced young women who had never used an IUD, we employed multinominal logit regression models to examine differences in IUD interest. FINDINGS: Twenty percent of women in the sample were interested in using an IUD in the future, 32% were not, and 48% were unsure. Women who thought IUDs were unattractive owing to the devices being inside their bodies, the need for provider insertion and removal, or the potential for pain during insertion were less likely to be interested in ever using an IUD. Those who found IUDs attractive owing to the ease of use, the ability to have sex without interruption or a barrier method, the option of a nonhormonal method, the potential length of use, the internal nature of the method, or the high level of effectiveness were more likely to be interested. CONCLUSIONS: These data suggest that young women's attitudes toward IUDs are strongly linked to their interest-or lack thereof-in using an IUD. Health care providers attuned to women's contraceptive preferences are well-poised to help their patients match with methods that best accommodate these preferences.

Windsor and Perry: reactions of siblings in same-sex and heterosexual couples.

The U.S. Supreme Court decisions in U.S. v. Windsor (570 U.S. 307) and Hollingsworth v. Perry (570 U.S. 399) created a focal point for public discussion of marriage equality for same-sex couples. This article reports the results of an exploratory study of the reactions of individuals currently or previously in same-sex couple relationships and a heterosexual sibling who is currently or previously married (N = 371) to the Supreme Court decisions. Thematic content analysis was used to explore participants' responses to an open-ended question on a survey. Reactions of individuals from same-sex couples revealed the following themes: (1) longitudinal perspectives on the advancement of rights for same-sex couples; (2) emotional responses celebrating the decisions or expressing relief; (3) affirmation of their relationship or rights; (4) practical consequences of the extension of rights; and (5) minority stress related to anticipation of future prejudice or discrimination. Themes in the heterosexual siblings' responses were (1) ally support; (2) flat support without emotion or elaboration; (3) indifference to or ignorance about the decisions; and (4) disapproval of the decisions. These themes are compared and discussed in light of prior research on reactions to marriage restriction debates and marriage (in)equality and family relationships.

The relationship between contraceptive features preferred by young women and interest in IUDs: an exploratory analysis.

CONTEXT: Little research has examined the relationship between women's preferences of contraceptive features and their interest in IUD use. Given high levels of contraceptive discontinuation and dissatisfaction, a better understanding of contraceptive preferences may support women in finding their optimal method and meeting their family planning goals. METHODS: Data from 382 heterosexual women aged 18-29 were collected via a 2012 Internet survey. Chi-square tests and multivariate, multinomial logistic regression models were used to examine relationships between contraceptive features preferred by women and their interest in IUD use. RESULTS: Forty-eight percent of women reported being unsure whether they would ever use an IUD; 20% were interested in using one, and 32% were not. In multivariate analyses, characteristics of a contraceptive method found positively associated with IUD interest were the method's not interfering with sexual pleasure (relative risk ratio, 3.4), being 99% effective without user action (2.5) and being effective for up to five years without any user action (3.8). Women who preferred a method that they could see or that would allow them to resume fertility immediately after discontinuation were less likely than those who did not to be interested in using rather than not using an IUD (0.4-0.5). CONCLUSIONS: The findings of this exploratory analysis indicate that women value a multitude of contraceptive features, which may have implications for their interest in using an IUD. Future research should consider the ways that women's contraceptive preferences can be incorporated into contraceptive counseling.

Willingness to use follow-up eye care services after vision screening in rural areas surrounding Chennai, India.

AIMS: To assess the willingness to utilise follow-up eye care services among participants of community vision screenings in rural villages surrounding Chennai. METHODS: Vision screening participants aged ≥40 years were selected by systematic sampling and were invited to respond to a pretested verbal survey with close-ended questions before undergoing screening. RESULTS: Two hundred and ninety-two people responded. Among the respondents, 50.3% reported experiencing an eye problem, and 53% of these individuals had never had an eye examination. Acceptance rate for eye surgery, medications, and eyeglasses among the respondents was 59.2%, 52.7% and 90.8%, respectively. These acceptances were not associated with sex, age, or employment; medication acceptance was inversely associated with literacy. Surgery acceptance and medication acceptance were associated with area of residence. Presence of another chronic disease was a predictor for surgery acceptance among respondents experiencing eye problems. CONCLUSIONS: Maintaining consistent quality of services delivered is crucial for increasing uptake of existing eye care services. Educational interventions may increase eye care service usage by targeting all demographic subgroups of rural populations equally. Additional interventions should be offered to patients without previous exposure to the healthcare system.