Cross-generational heritability analysis of physiological traits in Porites astreoides across an inshore-offshore gradient in the Lower Florida Keys

Coral Reefs - Estimating the heritable genetic variation in fitness-related traits is key to projecting the adaptive evolution of organisms in response to a changing environment. While heritability...     

Ecological species groups of landform-level ecosystems dominated by jack pine in northern Lower Michigan,USA

A combination of field and tabular methods and multivariate analyses were used to develop groups of ground flora species (i.e., ecological species groups) that characterize and distinguish highly disturbed, landform-level ecosystems dominated by jack pine in northern Lower Michigan. The endangered Kirtland's warbler formerly or currently occupied the large glacial landforms for which species groups were developed. Eight such ecological species groups were created using 31 woody and herbaceous species sampled in 144 plots within a 20,000 km² geographic region of uniform climate and regional physiography. The groups were initially constructed using subjective, observation-based groupings of species with similar presence and abundance along soil moisture and fertility gradients. Species groups were corroborated using TWINSPAN and detrended correspondence analysis, and the environmental conditions indicated by each were described and contrasted based upon field observations and canonical correspondence analysis. Two of the eight species groups indicated very dry, infertile sites, and one was indicative of a very broad range of sites dominated by jack pine. The remaining five groups reflected a relatively gentle environmental gradient within the set of ecosystems we sampled, indicating small differences along a soil moisture gradient and less so along a soil fertility and light availability gradient. The groups were applied successfully for the majority of an area that had been repeatedly logged and/or burned for at least 120 years. In addition, the groups were successful when tested on sites with highly disturbed upper soil strata furrowed for the establishment of plantations between the 1960s and 1980s. Within the boundaries of the regional ecosystems for which they were developed, ecological species groups reflect the integrated effects of multiple site factors that control the height growth rates of jack pine trees that, in turn, determine the duration of Kirtland's warbler occupancy. While usually applied at the scale of ecosystem types, our results demonstrate that ecological species groups may also provide the ecological basis for distinguishing ecosystems at broader scales. When examined simultaneously in the field with physiography, microclimate, and soil factors, the groups are therefore useful in identifying and classifying ecosystem units at the scale of landforms, the appropriate scale of management for the Kirtland's warbler.     

Genes,agents and the institution of responsible action

The concern of this paper is with how the accounts of human beings and their behaviour now emerging from genetics, genomics and the new human biotechnology should be related to traditional accounts in which we identify ourselves as responsible agents, capable of choice, who normally act freely and voluntarily. The paper addresses these apparently competing accounts in terms of their functions and modes of use, and thereby arrives at a general solution to this current version of the ancient problem of free will and determinism. The causal scientific discourse of genetics and the everyday discourse of responsibility and choice do different things for us, it suggests, and should not be regarded as articulating conflicting theories. Whilst the former is oriented to the task of naturalistic explanation, the latter is predominantly, if not entirely, a medium of communication through which we affect each other and thereby mutually regulate our conduct. If this is indeed the case, then interesting implications follow concerning the proper relationship of the two kinds of account, which need no longer be regarded as incompatible with each other. And insights emerge into both the limitations and the profound importance of the contribution that genetics and genomics seem destined to make to the understanding of human behaviour.     

Plant competition for light analyzed with a multispecies canopy model

Summary Competition for light among species in a mixed canopy can be assessed quantitatively by a simulation model which evaluates the importance of different morphological and photosynthetic characteristics of each species. A model was developed that simulates how the foliage of all species attenuate radiation in the canopy and how much radiation is received by foliage of each species. The model can account for different kinds of foliage (leaf blades, stems, etc.) for each species. The photosynthesis and transpiration for sunlit and shaded foliage of each species is also computed for different layers in the canopy. The model is an extension of previously described single-species canopy photosynthesis simulation models. Model predictions of the fraction of foliage sunlit and interception of light by sunlit and shaded foliage for monoculture and mixed canopies of wheat (Triticum aestivum) and wild oat (Avena fatua) in the field compared very well with measured values. The model was used to calculate light interception and canopy photosynthesis for both species of wheat/wild oat mixtures grown under normal solar and enhanced ultraviolet-B (290–320 nm) radiation (UV-B) in a glasshouse experiment with no root competition. In these experiments, measurements showed that the mixtures receiving enhanced UV-B radiation had a greater proportion of the total foliage area composed of wheat compared to mixtures in the control treatments. The difference in species foliage area and its position in the canopy resulted in a calculated increase in the portion of total canopy radiation interception and photosynthesis by wheat. This, in turn, is consistent with greater canopy biomass of wheat reported in canopies irradiated with supplemental UV-B.     

Genistein inhibition of the growth of human breast cancer cells: independence from estrogen receptors and the multi-drug resistance gene

The effect of isoflavones on the growth of the human breast carcinoma cell lines, MDA-468 (estrogen receptor negative), and MCF-7 and MCF-7-D-40 (estrogen receptor positive), has been examined. Genistein is a potent inhibitor of the growth of each cell line (IC50 values from 6.5 to 12.0 micrograms/ml), whereas biochanin A and daidzein are weaker growth inhibitors (IC50 values from 20 to 34 micrograms/ml). The isoflavone beta-glucosides, genistin and daidzin, have little effect on growth (IC50 values greater than 100 micrograms/ml). The presence of the estrogen receptor is not required for the isoflavones to inhibit tumor cell growth (MDA-468 vs MCF-7 cells). In addition, the effects of genistein and biochanin A are not attenuated by overexpression of the multi-drug resistance gene product (MCF-7-D40 vs MCF-7 cells).     

Conservation in a cup of water: estimating biodiversity and population abundance from environmental DNA

Three mantras often guide species and ecosystem management: (i) for preventing invasions by harmful species, ‘early detection and rapid response’; (ii) for conserving imperilled native species, ‘protection of biodiversity hotspots’; and (iii) for assessing biosecurity risk, ‘an ounce of prevention equals a pound of cure.’ However, these and other management goals are elusive when traditional sampling tools (e.g. netting, traps, electrofishing, visual surveys) have poor detection limits, are too slow or are not feasible. One visionary solution is to use an organism’s DNA in the environment (eDNA), rather than the organism itself, as the target of detection. In this issue of Molecular Ecology, Thomsen et al. (2012) provide new evidence demonstrating the feasibility of this approach, showing that eDNA is an accurate indicator of the presence of an impressively diverse set of six aquatic or amphibious taxa including invertebrates, amphibians, a fish and a mammal in a wide range of freshwater habitats. They are also the first to demonstrate that the abundance of eDNA, as measured by qPCR, correlates positively with population abundance estimated with traditional tools. Finally, Thomsen et al. (2012) demonstrate that next‐generation sequencing of eDNA can quantify species richness. Overall, Thomsen et al. (2012) provide a revolutionary roadmap for using eDNA for detection of species, estimates of relative abundance and quantification of biodiversity.     

Plant genome archaeology: evidence for conserved ancestral chromosome segments in dicotyledonous plant species

We have developed genetic maps, based on expressed sequence tags (ESTs) that are homologous to Arabidopsis genes, in four dicotyledonous crop plant species from different families. A comparison of these maps with the physical map of Arabidopsis reveals common genome segments that appear to have been conserved throughout the evolution of the dicots. In the four crop species analysed these segments comprise between 16 and 33% of the Arabidopsis genome. Our findings extend the synteny patterns previously observed only within plant families, and indicate that structural and functional information from the model species will be, at least in part, applicable in crop plants with large genomes.     

Does stream flow structure woody riparian vegetation in subtropical catchments?

The primary objective of this study was to test the relevance of hydrological classification and class differences to the characteristics of woody riparian vegetation in a subtropical landscape in Queensland, Australia. We followed classification procedures of the environmental flow framework ELOHA – Ecological Limits of Hydrologic Alteration. Riparian surveys at 44 sites distributed across five flow classes recorded 191 woody riparian species and 15, 500 individuals. There were differences among flow classes for riparian species richness, total abundance, and abundance of regenerating native trees and shrubs. There were also significant class differences in the occurrence of three common tree species, and 21 indicator species (mostly native taxa) further distinguished the vegetation characteristics of each flow class. We investigated the influence of key drivers of riparian vegetation structure (climate, depth to water table, stream‐specific power, substrate type, degree of hydrologic alteration, and land use) on riparian vegetation. Patterns were explained largely by climate, particularly annual rainfall and temperature. Strong covarying drivers (hydrology and climate) prevented us from isolating the independent influences of these drivers on riparian assemblage structure. The prevalence of species considered typically rheophytic in some flow classes implies a more substantial role for flow in these classes but needs further testing. No relationships were found between land use and riparian vegetation composition and structure. This study demonstrates the relevance of flow classification to the structure of riparian vegetation in a subtropical landscape, and the influence of covarying drivers on riparian patterns. Management of environmental flows to influence riparian vegetation assemblages would likely have most potential in sites dominated by rheophytic species where hydrological influences override other controls. In contrast, where vegetation assemblages are dominated by a diverse array of typical rainforest species, and other factors including broad‐scale climatic gradients and topographic variables have greater influence than hydrology, riparian vegetation is likely to be less responsive to environmental flow management.     

The interchangeability of global positioning system and semiautomated video-based performance data during elite soccer match play

In elite-level soccer, player motion characteristics are commonly generated from match play and training situations using semiautomated video analysis systems and global positioning system (GPS) technology, respectively. Before such data are used collectively to quantify global player load, it is necessary to understand both the level of agreement and direction of bias between the systems so that specific interventions can be made based on the reported results. The aim of this report was to compare data derived from both systems for physical match performances. Six elite-level soccer players were analyzed during a competitive match using semiautomated video analysis (ProZone? [PZ]) and GPS (MinimaxX) simultaneously. Total distances (TDs), high speed running (HSR), very high speed running (VHSR), sprinting distance (SPR), and high-intensity running distance (HIR; >4.0 m·s(-1)) were reported in 15-minute match periods. The GPS reported higher values than PZ did for TD (GPS: 1,755.4 ± 245.4 m; PZ: 1,631.3 ± 239.5 m; p < 0.05); PZ reported higher values for SPR and HIR than GPS did (SPR: PZ, 34.1 ± 24.0 m; GPS: 20.3 ± 15.8 m; HIR: PZ, 368.1 ± 129.8 m; GPS: 317.0 ± 92.5 m; p < 0.05). Caution should be exercised when using match-load (PZ) and training-load (GPS) data interchangeably.