Since its discovery, the annual migration of eastern North American monarch butterflies has captivated the human imagination and spirit. That millions of butterflies annually fly a few thousand miles to reach a cluster of pine groves in central Mexico comprising just 70 square miles is, for many, an awesome and mysterious occurrence. However, over the past two decades, scientists have begun to unveil the journey for what it is: a spectacular result of biology, driven by an intricate molecular mechanism in a tiny cluster of cells in the butterfly brain.

People who adopt four healthy behaviours – not smoking; taking exercise; moderate alcohol intake; and eating five servings of fruit and vegetables a day – live on average an additional fourteen years of life compared with people who adopt none of these behaviours, according to a study published in the open access journal PLoS Medicine.

A high-energy form of ultrasound imaging developed by researchers at Duke University's Pratt School of Engineering produces pictures of liver tumors that are better than those made with traditional ultrasound, according to results of a clinical study.

Rather than being gentle giants, new research reveals that Pleistocene cave bears ate both plants and animals and competed for food with the other contemporary large carnivores of the time: hyaenas, lions, wolves, and our own human ancestors.

Researchers have identified a new gene linked to cerebral venous thrombosis, a condition that causes blood clots in the veins of the brain that can lead to stroke. The condition is more common in young and middle-aged women. The research is published in the January 8, 2008, issue of Neurology®, the medical journal of the American Academy of Neurology.

A hemangioma is a benign tumor of cells that line blood vessels, appearing during the first few weeks of life as a large birthmark or lesion. A study published in Pediatric Dermatology reveals that a disturbance of oxygen depletion was found in placentas of babies who developed infantile hemangioma (IH).

Hybridizing blind cave fish from different cave populations can partially restore the vision of their offspring, biologists at New York University have found. The study suggests that genetic engineering can override, at least in part, half a million years of evolutionary change in one generation.

A new comparison of normal stem cells and cancer stem cells reveals that the cancer stem cells are abnormally trapped at an early stage of development. The research, published by Cell Press in the January issue of Cancer Cell, significantly advances the understanding of glioma pathophysiology and provides new directions for design of therapeutic strategies that are targeted to specific types of tumors.

Premature babies are subject to a host of threats that can result in fetal/neonatal disease. In a study published in the January 2008 issue of the American Journal of Obstetrics & Gynecology, researchers from the University of Alabama–Birmingham Medical School and the Drexel University College of Medicine found that genital mycoplasmas are a frequent cause of congenital fetal infection. 23% of neonates born between 23 and 32 weeks of gestation have positive umbilical blood cultures for two genital mycoplasmas (bacteria lacking cell walls): Ureaplasma urealyticum and Mycoplasma hominis.

University of California, Irvine infectious disease researchers have shown the effectiveness of a potential alternative to the existing smallpox vaccine that can replace the current biodefense stockpile for this lethal virus.

Exposure to air pollution significantly reduces foetus size during pregnancy, according to a new study by Brisbane scientists.

People who experience brief periods of blocked blood flow may be better conditioned to survive a full-blown heart attack later, according to new research from the University of Cincinnati (UC).