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A class of black holes of intermediate mass is expected but has never been detected. The suggestion that these beasts might lurk behind powerful X-ray sources in nearby galaxies is now strengthened.
The p27Kip1 protein inhibits cell proliferation, helping to prevent tumours developing. We now know that it also affects cell migration, by regulating Rho proteins. Does this function influence tumour progression?
The Mars saga continues. The latest finds — wide areas covered in balls of haematite, or ‘blueberries’, and large sulphate deposits in rocks — enable us to draw in more details of the planet's past climate.
The courtship of satin bowerbirds is a complicated business. Different parts of a male's display appeal to females of different ages, so age-biased variation might underlie the evolution of these displays.
Analyses that largely exploit indirect data from the past 150 years show that El Niño and La Niña might be more predictable than was thought. The results presage the prospect of extended climate forecasts.
Can we ever hope to pin down the genetic changes that underlie the big steps in evolution? Possibly so, if a study of the variation in the pelvic fins of sticklebacks is anything to go by.
What gives cooperation an evolutionary edge? Two features of a population — spatial structure and finite size — are factors in the success of any strategy, although more subtle than we thought.
At intervals, the polarity of the Earth's magnetic field reverses. The timescale for this reversal is unclear — in fact, it seems to depend on the latitude of the site from which the geological data are extracted.
The principle of the evolutionary cul-de-sac is commonly invoked to explain the apparent lingering existence of once-diverse groups of organisms. Maybe that principle itself has had its day.
Beautifully preserved specimens of butterflies from the Caribbean, caught maybe in the act of egg-laying some 20 million years ago, provide welcome grist to the mill of debate about butterfly history.
Publication of the rat genome sequence will not only advance physiological studies in this paragon of laboratory animals, but also greatly enhance the power of comparative research into mammalian genomes.
The history of how Earth's interior evolved, and how it accounts for many aspects of our planet's behaviour, remains largely unwritten. Taking water into account could well help to explain a great deal more.
