The effects of Hurricane Allen on Back Reef populations of Discovery Bay,Jamaica

Sixteen months after Hurricane Allen, an assessment of the condition (living vs. dead and encrusted) and volume of staghorn coral, Acropora cervicomis Lamarck, patches within the East Back Reef of Discovery Bay, Jamaica was made. Data generated by this assessment were compared with similar data collected in 1975–1976 prior to the storm. Densities of two urchins, Diadema antillarum Philippi and Echinometra viridis A. Agassiz, and the threespot damselfish, Eupomacentrus planifrons Cuvier, within the coral patches were also measured.Although staghorn coral patches were significantly smaller (? 65%) in mean volume in 1981 compared to 1975–1976, 22% of the patches were unchanged since 1976 or had increased in volume and only 9% were reduced to piles of rubble. Diadema and threespot densities were significantly higher than in 1976. Mortality of damselfish and larger Diadema appeared to have been reduced. Coral patches with both damselfish and Diadema present exhibited a high proportion of living coral tissue, while those patches dominated by either damselfish or Diadema were overgrazed with < 5% of the substrata covered by living coral. Similarly, the fore reef exhibited high urchin and low damselfish densities, possibly contributing to its low proportion of living coral.     

The application of statistical decision theory to animal behaviour

Statistical decision theory is discussed as a general framework for analysing how animals should learn. Attention is focused on optimal foraging behaviour in stochastic environments. We emphasise the distinction between the mathematical procedure that can be used to find optimal solutions and the mechanism an animal might use to implement such solutions. The mechanisms might be specific to a restricted class of problems and produce suboptimal behaviour when faced with problems outside this class. We illustrate this point by an example based on what is known in the literature on animal learning as the partial reinforcement effect.     

Species diversity and phylogeography of Cornus kousa (Asian dogwood) captured by genomic and genic microsatellites

Cornus kousa (Asian dogwood), an East Asia native tree, is the most economically important species of the dogwood genus, owing to its desirable horticultural traits and ability to hybridize with North America‐native dogwoods. To assess the species genetic diversity and to better inform the ongoing and future breeding efforts, we assembled an herbarium and arboretum collection of 131 noncultivated C. kousa specimens. Genotyping and capillary electrophoresis analyses of our C. kousa collection with the newly developed genic and published nuclear genomic microsatellites permitted assessment of genetic diversity and evolutionary history of the species. Regardless of the microsatellite type used, the study yielded generally similar insights into the C. kousa diversity with subtle differences deriving from and underlining the marker used. The accrued evidence pointed to the species distinct genetic pools related to the plant country of origin. This can be helpful in the development of the commercial cultivars for this important ornamental crop with increased pyramided utility traits. Analyses of the C. kousa evolutionary history using the accrued genotyping datasets pointed to an unsampled ancestor population, possibly now extinct, as per the phylogeography of the region. To our knowledge, there are few studies utilizing the same gDNA collection to compare performance of genomic and genic microsatellites. This is the first detailed report on C. kousa species diversity and evolutionary history inference.     

Hindcasting Historical Breeding Conditions for an Endangered Salamander in Ephemeral Wetlands of the Southeastern USA: Implications of Climate Change

The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders (Ambystoma bishopi), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A. bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006–2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896–2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A. bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A. bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions.     

Oligopeptide Signaling through TbGPR89 Drives Trypanosome Quorum Sensing

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Role of Weight History on Functional Limitations and Disability in Late Adulthood: The ARIC Study

Objective: To examine associations of weight history with functional limitations and disability in white and African‐American men and women. Research Methods and Procedures: Data were from the Atherosclerosis Risk in Communities study (n = 11, 177). Associations of recalled weight status at age 25 and weight change from age 25 to ages 45 to 64 with functional limitations, activities of daily living (ADLs), and instrumental activities of daily living (IADLs) at follow‐up (ages 52 to 75) were examined using logistic regression. Results: Obesity (BMI ≥ 30 kg/m²) at age 25 was associated with functional limitations and ADL and IADL impairment at follow‐up in white and African‐American men and women. For example, obese compared with normal weight (BMI, 18.5 to 24.9 kg/m²) white women had higher odds of mild [odds ratio (95% confidence interval), 1.97 (1.18 to 3.29)] and severe [9.81 (5.92 to 16.27)] functional limitations and ADL [3.48 (2.36 to 5.13)] and IADL [2.95 (2.00 to 4.33)] impairment. In African‐American women, obesity was associated with higher odds of mild [2.71 (1.14 to 6.41)] and severe [6.01 (2.53 to 14.26)] functional limitations and ADL [1.82 (1.10 to 3.00)] and IADL [2.39 (1.47 to 3.90)] impairment. Similar associations were found in men. Compared with weight maintenance (±10 lbs), large weight gain (>30 lbs) from age 25 to ages 45 to 64 was also associated with functional limitations and ADL and IADL impairment in white and African‐American men and women. Discussion: Maintenance of a healthy body weight throughout adulthood may play a role in preventing or delaying the onset of functional limitations and disability, resulting in increased quality of life and decreased health care costs.