The gruesome new field of neuro-parasitology could provide insights into the neurological basis for behavior and decision-making — By Conn Hastings Imagine a parasite that makes an animal change its habits, guard the parasite’s offspring or even commit suicide.

Jaroslav Flegr is no kook. And yet, for years, he suspected his mind had been taken over by parasites that had invaded his brain. So the prolific biologist took his science-fiction hunch into the lab. What he’s now discovering will startle you. Could tiny organisms carried by house cats be creeping into our brains, causing everything from car wrecks to schizophrenia? A biologist’s science- fiction hunch is gaining credence and shaping the emerging science of mind- controlling parasites.

Biology used to be about plants, animals and insects, but five great revolutions have changed the way that scientists think about life: the invention of the microscope, the systematic classification of the planet's living creatures, evolution, the discovery of the gene and the structure of DNA. Now, a sixth is on its way - mathematics.

Maths has played a leading role in the physical sciences for centuries, but in the life sciences it was little more than a bit player, a routine tool for analysing data. However, it is moving towards centre stage, providing new understanding of the complex processes of life.

The ideas involved are varied and novel; they range from pattern formation to chaos theory. They are helping us to understand not just what life is made from, but how it works, on every scale from molecules to the entire planet - and possibly beyond.

Parasites commonly manipulate host behaviour, and among the most dramatic examples are diverse fungi that cause insects to die attached to leaves. This death-grip behaviour functions to place insects in an ideal location for spore dispersal from a dead body following host death. Fossil leaves record many aspects of insect behaviour (feeding, galls, leaf mining) but to date there are no known examples of behavioural manipulation. Here, we document, to our knowledge, the first example of the stereotypical death grip from 48 Ma leaves of Messel, Germany, indicating the antiquity of this behaviour. As well as probably being the first example of behavioural manipulation in the fossil record, these data support a biogeographical parallelism between mid Eocene northern Europe and recent southeast Asia.

So what would happen if there were none? Would anyone or anything miss them? Nature put this question to scientists who explore aspects of mosquito biology and ecology, and unearthed some surprising answers.

There are 3,500 named species of mosquito, of which only a couple of hundred bite or bother humans. They live on almost every continent and habitat, and serve important functions in numerous ecosystems. "Mosquitoes have been on Earth for more than 100 million years," says Murphy, "and they have co-evolved with so many species along the way." Wiping out a species of mosquito could leave a predator without prey, or a plant without a pollinator. And exploring a world without mosquitoes is more than an exercise in imagination: intense efforts are under way to develop methods that might rid the world of the most pernicious, disease-carrying species (see 'War against the winged').

A spider that only eats ants is choosy about which body parts of its prey it devours based on their nutritional value.

These new findings are the first to demonstrate that "specialist" predators relying on a single food source might have evolved feeding behaviors to maximize what they get out of meal time, the researchers say.

"We found that these spiders do have to balance their nutrient intake by choosing different body parts of their exclusive ant prey," said Stano Pekár, an assistant professor of ecology and zoology at Masaryk University in the Czech Republic and lead author of the research published in the April 15 issue of the journal Animal Behaviour.

When chowing down on ants, the spiders consistently began with the protein-packed front parts before getting to the fattier hind segment, called a gaster or abdomen. The picky eating seemed to pay off: Spiders reared on just front-end ant pieces grew faster, bigger and lived longer than those served only gasters or even whole an

Want to know what life will look like on other planets? Look no farther than these five creatures, who are already prepared for life on Saturn's moon Titan - or in the hard vacuum of deep space.

Unlike humans, with our pesky need for things like oxygen and sugar, some creatures are more flexible in the habitats where they feel comfortable. Here are five lifeforms who are prepared to live on other planets right now.