Links between plant and fungal communities across a deforestation chronosequence in the Amazon rainforest

Understanding the interactions among microbial communities, plant communities and soil properties following deforestation could provide insights into the long-term effects of land-use change on ecosystem functions, and may help identify approaches that promote the recovery of degraded sites. We combined high-throughput sequencing of fungal rDNA and molecular barcoding of plant roots to estimate fungal and plant community composition in soil sampled across a chronosequence of deforestation. We found significant effects of land-use change on fungal community composition, which was more closely correlated to plant community composition than to changes in soil properties or geographic distance, providing evidence for strong links between above- and below-ground communities in tropical forests.     

A chance field observation and pilor laboratory studies of predation of the New Zealand flatworm by the larvae and adults of carabid and staphylinid beetles

A chance finding in an Edinburgh allotment was made of a stained carabid beetle larva that had eaten Artioposthiu triungulata previously stained red and released into the allotment during a dispersal experiment. In a pilot laboratory study the flatworm was eaten by larval and adult carabid and staphylinid beetles whereas seven other carnivorous species from five arthropod families did not. In another feeding experiment a carabid and a staphylinid larva each ate several specimens of the flatworm and gained tissue weight over 14 days. The conclusion drawn from these preliminary studies and the field observation is that certain carabid and staphylinid beetles are potential predators of A. triangulata.     

HUMAN NATURE AND ENHANCEMENT

Appeals to the idea of human nature are frequent in the voluminous literature on the ethics of enhancing human beings through biotechnology. Two chief concerns about the impact of enhancements on human nature have been voiced. The first is that enhancement may alter or destroy human nature. The second is that if enhancement alters or destroys human nature, this will undercut our ability to ascertain the good because, for us, the good is determined by our nature. The first concern assumes that altering or destroying human nature is in itself a bad thing. The second concern assumes that human nature provides a standard without which we cannot make coherent, defensible judgments about what is good.
I will argue (1) that there is nothing wrong, per se, with altering or destroying human nature, because, on a plausible understanding of what human nature is, it contains bad as well as good characteristics and there is no reason to believe that eliminating some of the bad would so imperil the good as to make the elimination of the bad impermissible, and (2) that altering or destroying human nature need not result in the loss of our ability to make judgments about the good, because we possess a conception of the good by which we can and do evaluate human nature. I will argue that appeals to human nature tend to obscure rather than illuminate the debate over the ethics of enhancement and can be eliminated in favor of more cogent considerations.     

Satellite DNA repeat sequence variation is low in three species of burying beetles in the genus Nicrophorus (Coleoptera: Silphidae)

Three satellite DNA families were identified in three species of burying beetles, Nicrophorus orbicollis, N. marginatus, and N. americanus. Southern hybridization and nucleotide sequence analysis of individual randomly cloned repeats shows that these satellite DNA families are highly abundant in the genome, are composed of unique repeats, and are species-specific. The repeats do not have identifiable core elements or substructures that are similar in all three families, and most interspecific sequence similarity is confined to homopolymeric runs of A and T. Satellite DNA from N. marginatus and N. americanus show single-base-pair indels among repeats, but single-nucleotide substitutions characterize most of the repeat variability. Although the repeat units are of similar lengths (342, 350, and 354 bp) and A + T composition (65%, 71%, and 71%, respectively), the average nucleotide divergence among sequenced repeats is very low (0.18%, 1.22%, and 0.71%, respectively). Transition/transversion ratios from the consensus sequence are 0.20, 0.69, and 0.70, respectively.      

PRIVATIZATION AND JUST HEALTHCARE

When advocates of insurance-privatization consider whether private insurance-dominated systems achieve justice at all, they tend to rely on an incomplete set of criteria for a just healthcare system. They also mistakenly assume that it is enough to show that justice is in principle achievable within a private insurance-dominated system. This essay offers a more complete set of criteria for a just healthcare system. It then argues that the motivational assumptions needed to make insurance-privatization at all plausible (on grounds of choice, efficiency, and quality of care) are inconsistent with the motivational assumptions needed to show that in practice a private insurance-dominated system will achieve justice. A private insurance-dominated system can be expected to satisfy the criteria for just healthcare only if (a) there is extensive and effective regulation to constrain the normal competitive behavior of private insurers or if (b) generous public funds are provided to fill the gaps in access left by the private insurance market. Yet the assumptions about the motivations and abilities of the public, regulators, and public officials needed to satisfy conditions (a) or (b) contradict the privatization advocate's explanations of how privatization will maximize efficiency, choice, and quality of care