Reviews & Analysis

The invention of oxygenic photosynthesis was a small step for a bacterium, but a giant leap for biology and geochemistry. So when and how did cells first learn to split water to make oxygen gas?

Transposable elements were long dismissed as useless, but they are emerging as major players in evolution. Their interactions with the genome and the environment affect how genes are translated into physical traits.

The social activities and organization of bacteria are crucial to their ecological success. But it is only in recent years that we have begun to study these secret societies.

How did dinosaurs stand and move? Computer simulation and other methods have told us much about how dinosaurs did and did not move, but they have not yet reached their full potential.

To realize the potential of the genome for identifying candidate drugs we must move beyond individual genes and proteins. The signalling pathways in cells provide the right level for such analyses.

The term RNAi — short for RNA interference — crops up again and again in biology research these days. This is in part because of its power as a laboratory tool, and in part because it is a widespread natural phenomenon.

What determines how long we will live? Studies of simple organisms, single cells and mammals hint that certain shared principles underlie ageing, and raise the possibility of devising ways to extend life — if we want to.

Why, when the human race shows comparatively little genetic variation, are cultural differences so widespread and enduring? Thinking about cultures in terms of biological species provides some provocative answers.

A neglected mathematical theory is enjoying new popularity, thanks to its relevance to network dynamics in biological systems. The beating of a leech's heart is just one example that has a mathematical basis in ‘groupoid theory’.

Matter dominates antimatter, at least in our corner of the Universe. Part of the explanation could be an imbalance between the two at the level of fundamental interactions, encapsulated in the phenomenon of CP violation.

Why is the prevalence of type 2 diabetes mellitus now exploding in most populations, but not in Europeans? The genetic and evolutionary consequences of geographical differences in food history may provide the answer.

Evidence for the existence of dark matter in the Universe is overwhelming. But how close are we to finding out what it really is?

Natural philosophers have speculated on the existence of worlds around other suns for millennia. Now that real data are available, we find a diversity far beyond that expected by scientists, or science-fiction writers.

It is seven years since the first bacterial genome was completely sequenced, and more than 60 others have now been determined. What has been the impact of these projects on pure science and public welfare?

Plant stem cells, contained in specialized structures called meristems, have amazing regenerative powers. They enable plants to grow and produce new organs throughout lifetimes that can span hundreds of years.

Supramolecular chemistry has grown in importance because it goes beyond the molecule — the focus of classical chemistry. It also offers a fresh interface with biological and materials science.

The study of how cells communicate impinges on all aspects of biology, from development to disease. At first glance it's a horrendously complicated business, but some simple themes are emerging.

Quantum theory is 100 years old and still going strong. Combininggeneral relativity with quantum mechanics is the last hurdle to be overcomein the 'quantum revolution'.

The p53 tumour-suppressor gene integrates numerous signals that control cell life and death. As when a highly connected node in the Internet breaks down, the disruption of p53 has severe consequences.

Studies of stem cells will help in understanding the development and function of organs in mammals. They may also offer a way of treating diseases ranging from liver failure to Parkinson's disease.