Reviews & Analysis

Wolbachia bacteria infect insects and can cause mating incompatibilities, an outcome that is used to fight insect-transmitted disease. The proposed genes responsible illuminate this process and the disease-control mechanisms. See Letter p.243

Global sea levels would rise by several metres if the Greenland Ice Sheet melted completely. Two studies have examined its past behaviour in an effort to evaluate its vulnerability in a warming world — and have come to seemingly conflicting conclusions. Two geochemists and a glaciologist discuss the issues. See Letters p.252 & p.256

Neuroscientists are increasingly using virtual reality to facilitate studies of animal behaviour, but whether behaviour in the virtual world mimics that in real life is a matter for debate. Here, scientists discuss the strengths and limitations of the approach.

Our knowledge of how Earth's natural satellite formed is increasingly being challenged by observations and computer simulations. Two scientists outline our current understanding from the point of view of the satellite's geochemistry and its early dynamical history.

Analysis of cancer genomes is moving beyond the confines of a particular disease — researchers are now comparing the genetic and epigenetic characteristics of multiple tumour types. Two scientists comment on what such studies can teach us about cancer biology and how they may guide clinical practice. See Article p.333

An innovative assessment of climate change calculates the year in which ongoing warming will surpass the limits of historical climate variability. Three experts explain this calculation's significance compared with conventional approaches, and its relevance to Earth's biodiversity. See Article p.183

The finding that the shells of certain algae can contain a signature of low levels of atmospheric carbon dioxide has prompted the discovery of the emergence of this signature in the fossil record. Here, experts discuss the implications of this for climate science and ocean ecology. See Letter p.558

Research shows how the malaria parasite Plasmodium falciparum manipulates the expression of its var genes to avoid recognition by the host immune system. Four experts comment on the implications of these results for our understanding of gene regulation in general and the development of antimalaria vaccines. See Letter p.223

An investigation of droplet freezing in clouds suggests that a minor component of mineral dust in the atmosphere is the main catalyst for this process. Two experts discuss the ramifications of this finding for those investigating cloud-droplet freezing, and for scientists studying atmospheric aerosols. See Letter p.355

Niels Bohr's model of the structure of the atom raised the question of how large an atom can be. One hundred years on, the issue is still unresolved. Two physicists discuss the theoretical limits of atomic and nuclear size.

The elusive pear shapes of certain nuclei, which are challenging to predict theoretically, have at last been measured precisely. Two experts offer their views on what the results mean for nuclear physics and particle physics. See Article p.199

Physicists have come up with a way to characterize and command untrusted quantum systems. Two experts discuss the significance of these findings for fundamental science and for practical quantum computation and cryptography. See Article p.456

Our planet's soils teem with microorganisms that regulate processes from crop productivity to carbon sequestration. Molecular analysis contributes hugely to the characterization of microbial communities, but how can we better understand their ecological functions? Two microbiologists discuss the advantages of data-mining approaches versus targeted experiments.

A process called long-term potentiation mediates information storage — learning and memory — at the level of neurons. An in vitro study turns the molecular understanding of this process on its head. But researchers' opinions differ as to what can be inferred from these data. See Article p.495

Some worker fire ants will tolerate multiple queens in their colony, but others only one. It turns out that this behaviour is governed by a gene cluster on an unusual pair of chromosomes. Two scientists describe what these findings mean to the fields of social evolution, genetics and beyond. See Letter p.664

Synthetic chemistry has long been used to prepare useful compounds — especially those that are hard to obtain from natural sources. But synthetic biology is coming of age as an alternative strategy. A biologist and two chemists debate the merits of their fields' synthetic prowess.

Fossils found in rocks of the Ediacaran period in Australia have been previously characterized as early marine organisms. But a report suggests that these rocks are fossilized soils. So did some of these Ediacaran organisms in fact live on land, like lichens? A palaeontologist and a geologist weigh up the evidence. See Letter p.89

A phylogenetic reconstruction of the diversification of birds across space and time provides a novel resource for evolutionary studies. But the methods used to construct this tree, and what insights can be inferred from it, are a source of debate. Two evolutionary biologists provide opinions on how to draw the lines. See Letter p.444

Anthropogenic aerosols in the atmosphere undoubtedly influence climate. But do the approaches taken in climate models to account for the effects of aerosols provide meaningful estimates of those effects? Two climate scientists offer their opinions.

The Encyclopedia of DNA Elements (ENCODE) project dishes up a hearty banquet of data that illuminate the roles of the functional elements of the human genome. Here, six scientists describe the project and discuss how the data are influencing research directions across many fields. See Articles p.57, p.75, p.83, p.91, p.101 & Letter p.109