Bush medicine in the Exumas and long island,bahamas a field study

Reports from native informants backed with voucher plant specimens were obtained in a 1969–1970 field study on the Bahama islands of Great Exuma, Little Exuma and Long Island. Over 130 plant species of some 60 families are used within this culture for a wide variety of medicinal purposes. Pertinent background material and personal observations during field work indicated that knowledge of “bush medicine” is fading. The information recorded includes common names of each medicinal plant, uses, and preparations. A systematic list cross-referenced with common names is provided.     

Longitudinal patterns of breakfast eating in black and white adolescent girls

Objective: The objective was to describe the pattern of breakfast eating over time (“breakfast history”) and examine its associations with BMI and physical activity. Research Methods and Procedures: This longitudinal investigation of patterns of breakfast eating included 1210 black and 1161 white girls who participated in the 10‐year, longitudinal National Heart, Lung, and Blood Institute Growth and Health Study (NGHS). Three‐day food records were collected during annual visits beginning at ages 9 or 10 up to age 19. Linear regression and path analysis were used to estimate the associations between breakfast history, BMI, and physical activity. Results: Among girls with a high BMI at baseline, those who ate breakfast more often had lower BMI at the end of the study (age 19), compared with those who ate breakfast less often. Path analysis indicated that energy intake and physical activity mediated the association between patterns of breakfast eating over time and BMI in late adolescence. Discussion: The association between regular breakfast consumption over time and moderation of body weight among girls who began the study with relatively high BMI suggests that programs to address overweight in children and adolescents should emphasize the importance of physical activity and eating breakfast consistently.     

Mapping the distribution of the telomeric sequence (T2AG3)n in the Macropodoidea (Marsupialia) by fluorescence in situ hybridization. II. The ancestral 2n = 22 macropodid karyotype

In marsupial karyotypes with little heterochromatin, the telomeric sequence (T(2)AG(3))(n), is involved in chromosome rearrangements. Here we compare the distribution of the (T(2)AG(3))(n) sequence in chromosomes recently derived by fusions and other rearrangements (7-0.5 MYBP) with its distribution in chromosomes derived earlier (24-9 MYBP). We have previously shown that the (T(2)AG(3))(n) sequence is consistently retained during chromosome rearrangements that are recent (7-0.5 MYBP). We suggest that in less recent rearrangements (24-9 MYBP) the pattern observed is initial retention followed by loss or amplification. We also suggest that the presence of interstitial (T(2)AG(3))(n) sequence is related to the evolutionary status of single chromosomes rather than entire karyotypes.     

Diversity at the major histocompatibility complex Class II in the platypus, Ornithorhynchus anatinus

The platypus (Ornithorhynchus anatinus) is the sole survivor of a previously widely distributed and diverse lineage of ornithorhynchid monotremes. Its dependence on healthy water systems imposes an inherent sensitivity to habitat degradation and climate change. Here, we compare genetic diversity at the major histocompatibility complex (MHC) Class II-DZB gene and 3 MHC-associated microsatellite markers with diversity at 6 neutral microsatellite markers in 70 platypuses from across their range, including the mainland of Australia and the isolated populations of Tasmania, King Island, and Kangaroo Island. Overall, high DZB diversity was observed in the platypus, with 57 DZB β1 alleles characterized. Significant positive selection was detected within the DZB peptide-binding region, promoting variation in this domain. Low levels of genetic diversity were detected at all markers in the 2 island populations, King Island (endemic) and Kangaroo Island (introduced), with the King Island platypuses monomorphic at the DZB locus. Loss of MHC diversity on King Island is of concern, as the population may have compromised immunological fitness and reduced ability to resist changing environmental conditions.     

Soil nutrients under shrub hummocks and debris mounds two decades after ploughing

Aims

Shrub removal by ploughing has been used widely to reduce the effects of shrub encroachment into open woodlands and grasslands. Our aim was to demonstrate that soil chemical properties varied markedly among three patch types (shrub hummock, debris mound, interspace) which varied in age, almost two decades after shrub removal by ploughing.

Methods

We compared changes in nutrients under 1) young post-ploughing recruits and mature, unploughed shrubs, 2) mature and recently formed debris mounds and 3) ploughed and recovering interspaces at three depths.

Results

Irrespective of their age, nutrient concentrations were greater under shrub hummocks and debris mounds than in the interspaces at two sites. Soil in mature shrub hummocks generally had greater levels of labile carbon and nitrogen (total, mineral, mineralisable), but results varied between sites. There were a few, sometimes inconsistent, effects of ploughing on nutrients under debris mounds, and no differences between the interspaces two decades after ploughing. Nutrient effects were most marked in the top 15 cm of the soil, diminishing rapidly with depth.

Conclusions

Our results reinforce the importance of hummocks and mounds as resource sinks and indicate the long-lasting effects of disturbances such as ploughing on soil nutrient pools.     

Multiple biogeographical barriers identified across the monsoon tropics of northern Australia: phylogeographic analysis of the brachyotis group of rock-wallabies

The monsoon tropics of northern Australia are a globally significant biodiversity hotspot, but its phylogeography is poorly known. A major challenge for this region is to understand the biogeographical processes that have shaped the distribution and diversity of taxa, without detailed knowledge of past climatic and environmental fluctuations. Although molecular data have great potential to address these questions, only a few species have been examined phylogeographically. Here, we use the widely distributed and abundant short-eared rock-wallaby (Petrogale brachyotis; n = 101), together with the sympatric monjon (P. burbidgei; n = 11) and nabarlek (P. concinna; n = 1), to assess historical evolutionary and biogeographical processes in northern Australia. We sequenced ～1000 bp of mitochondrial DNA (control region, ND2) and ～3000 bp of nDNA (BRCA1, ω-globin and two anonymous loci) to investigate phylogeographic structuring and delineate the time-scale of diversification within the region. Our results indicate multiple barriers between the Top End (Northern Territory) and Kimberley (Western Australia), which have caused divergence throughout the Plio-Pleistocene. Eight geographically discrete and genetically distinct lineages within the brachyotis group were identified, five of which are separated by major river valleys (Ord, Victoria, Daly), arid lowlands and discontinuous sandstone ranges. It is likely that these barriers have similarly influenced genetic structure in other monsoonal biota.     

Identification of the determinants for the specific recognition of single-strand telomeric DNA by Cdc13

The single-strand overhang present at telomeres plays a critical role in mediating both the capping and telomerase regulation functions of telomeres. The telomere end-binding proteins, Cdc13 in Saccharomyces cerevisiae, Pot1 in higher eukaryotes, and TEBP in the ciliated protozoan Oxytricha nova, exhibit sequence-specific binding to their respective single-strand overhangs. S. cerevisiae telomeres are composed of a heterogeneous mixture of GT-rich telomeric sequence, unlike in higher eukaryotes which have a simple repeat that is maintained with high fidelity. In yeast, the telomeric overhang is recognized by the essential protein Cdc13, which coordinates end-capping and telomerase activities at the telomere. The Cdc13 DNA-binding domain (Cdc13-DBD) binds these telomere sequences with high affinity (3 pM) and sequence specificity. To better understand the basis for this remarkable recognition, we have investigated the binding of the Cdc13-DBD to a series of altered DNA substrates. Although an 11-mer of GT-rich sequence is required for full binding affinity, only three of these 11 bases are recognized with high specificity. This specificity differs from that observed in the other known telomere end-binding proteins, but is well suited to the specific role of Cdc13 at yeast telomeres. These studies expand our understanding of telomere recognition by the Cdc13-DBD and of the unique molecular recognition properties of ssDNA binding.     

Restricted mating dispersal and strong breeding group structure in a mid-sized marsupial mammal (Petrogale penicillata)

Ecological genetic studies have demonstrated that spatial patterns of mating dispersal, the dispersal of gametes through mating behaviour, can facilitate inbreeding avoidance and strongly influence the structure of populations, particularly in highly philopatric species. Elements of breeding group dynamics, such as strong structuring and sex-biased dispersal among groups, can also minimize inbreeding and positively influence levels of genetic diversity within populations. Rock-wallabies are highly philopatric mid-sized mammals whose strong dependence on rocky terrain has resulted in series of discreet, small colonies in the landscape. Populations show no signs of inbreeding and maintain high levels of genetic diversity despite strong patterns of limited gene flow within and among colonies. We used this species to investigate the importance of mating dispersal and breeding group structure to inbreeding avoidance within a 'small' population. We examined the spatial patterns of mating dispersal, the extent of kinship within breeding groups, and the degree of relatedness among brush-tailed rock-wallaby breeding pairs within a colony in southeast Queensland. Parentage data revealed remarkably restricted mating dispersal and strong breeding group structuring for a mid-sized mammal. Breeding groups showed significant levels of female kinship with evidence of male dispersal among groups. We found no evidence for inbreeding avoidance through mate choice; however, anecdotal data suggest the importance of life history traits to inbreeding avoidance between first-degree relatives. We suggest that the restricted pattern of mating dispersal and strong breeding group structuring facilitates inbreeding avoidance within colonies. These results provide insight into the population structure and maintenance of genetic diversity within colonies of the threatened brush-tailed rock-wallaby.