2 research outputs found
Evolution of Anolis Lizard Dewlap Diversity
BACKGROUND: The dewlaps of Anolis lizards provide a classic example of a complex signaling system whose function and evolution is poorly understood. Dewlaps are flaps of skin beneath the chin that are extended and combined with head and body movements for visual signals and displays. They exhibit extensive morphological variation and are one of two cladistic features uniting anoles, yet little is known regarding their function and evolution. We quantified the diversity of anole dewlaps, investigated whether dewlap morphology was informative regarding phylogenetic relationships, and tested two separate hypotheses: (A) similar Anolis habitat specialists possess similar dewlap configurations (Ecomorph Convergence hypothesis), and (B) sympatric species differ in their dewlap morphologies to a greater extent than expected by chance (Species Recognition hypothesis). METHODOLOGY/PRINCIPAL FINDINGS: We found that dewlap configurations (sizes, patterns and colors) exhibit substantial diversity, but that most are easily categorized into six patterns that incorporate one to three of 13 recognizable colors. Dewlap morphology is not phylogenetically informative and, like other features of anoles, exhibits convergence in configurations. We found no support for the Ecomorph Convergence hypothesis; species using the same structural habitat were no more similar in dewlap configuration than expected by chance. With one exception, all sympatric species in four communities differ in dewlap configuration. However, this provides only weak support for the Species Recognition hypothesis because, due to the great diversity in dewlap configurations observed across each island, few cases of sympatric species with identical dewlaps would be expected to co-occur by chance alone. CONCLUSIONS/SIGNIFICANCE: Despite previous thought, most dewlaps exhibit easily characterizable patterns and colorations. Nevertheless, dewlap variation is extensive and explanations for the origin and evolution of this diversity are lacking. Our data do not support two hypothesized explanations for this diversity, but others such as sexual selection remain to be tested
Health Care Access and Breast Cancer Screening Among Latinas Along the California–Mexican Border
Latinas are more likely to exhibit late stage breast cancers at the time of diagnosis and have lower survival rates compared to white women. A contributing factor may be that Latinas have lower rates of mammography screening. This study was guided by the Behavioral Model of Health Services Use to examine factors associated with mammography screening utilization among middle-aged Latinas. An academic–community health center partnership collected data from community-based sample of 208 Latinas 40 years and older in the San Diego County who completed measures assessing psychosocial factors, health care access, and recent mammography screening. Results showed that 84.6 % had ever had a mammogram and 76.2 % of women had received a mammogram in the past 2 years. Characteristics associated with mammography screening adherence included a lower acculturation (OR 3.663) a recent physician visit in the past year (OR 6.304), and a greater confidence in filling out medical forms (OR 1.743), adjusting for covariates. Results demonstrate that an annual physical examination was the strongest predictor of recent breast cancer screening. Findings suggest that in this community, improving access to care among English-speaking Latinas and addressing health literacy issues are essential for promoting breast cancer screening utilization
