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Interest in nitric oxide has exploded in recent years following the recognition that manipulating the nitric oxide signalling pathway can have major medical benefits.

The Icelandic population of black-tailed godwits, which winter in Britain, has been increasing, so poor British estuarine habitats must be used as well as good ones. This might provide a mechanism for population control.

King penguin chicks are fed by a parent who goes off to sea to forage. Colonies of these birds can be huge and noisy, meaning that there is potentially a problem for the chick in identifying the calls of the returning parent. Experiments involving playback of calls show that the chicks have remarkable abilities to pick out those of their parent against the background din.

Every spring, leaves unfold from tightly packed buds. But how are they packed within these buds to allow efficient expansion at the right time? A study into the geometry of unfolding, for the leaves of two species of deciduous tree, indicates that folding depends on a number of design parameters. These include the shape of the leaf, and angle at which the folds run relative to the midrib of the expanded leaf.

Striking instances of larval metamorphosis, and of adult sexual dimorphism, are not uncommon in the animal world. But especially dramatic examples of these phenomena have emerged from the deep sea.

Winners refreshed economics with science and human nature.

Copepods are dominant constitutents of the marine zooplankton, and so are central players in the dynamics of ocean ecosystems. The seemingly arcane business of how they find mates and copulate is, then, a matter of some importance. Increasingly it is emerging that these tiny creatures are not completely at the mercy of the viscous forces of water, as might be expected -- rather, their mating behaviour involves the sensing and pursuit of complex patterns of hydomechanical and chemical signals.

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The Nobel committee has once again sparked controversy with the award last week of the 1998 prize for Physiology or Medicine to three US-based pharmacologists for their discoveries concerning nitric oxide as a signaling molecule in the cardiovascular system.

Pity the poor reed warbler parents that have a cuckoo egg laid in their nest. Not only does the cuckoo fledgling eject the reed warblers' young, but it then persuades its hosts to feed it at a rate equivalent to feeding an entire brood of its own nestlings. Some ingenious field and laboratory experiments have exposed the cues concerned. It turns out that the cuckoo chick's begging call, a continuous and rapid ‘si, si, si, si’ is quite unlike that of an individual reed warbler chick, but closely resembles that of an entire brood of them. Vocal trickery, then, seems to be the explanation for why the reed warbler parents are fooled into the accelerated provisioning rate.

The social instincts of a colourful coral reef fish, known as the Moorish idol, are the subject of a posthumous paper by Konrad Lorenz. It describes Lorenz's observations between 1976 and 1978 of how Moorish idols develop from typical antisocial teenagers into fully integrated members of aquarium society.