There may be less than 20,000 rhinoceros in the world, with one species perhaps already extinct and another with possibly only four animals remaining in the wild. As the populations of these animals age and become infirm, successful breeding becomes increasingly difficult. In an article scheduled for publication in Theriogenology, An International Journal of Animal Reproduction, researchers from the Leibniz Institute for Zoo and Wildlife Research, Berlin, Zoo Budapest and the University of Veterinary Medicine, Vienna, report on the first live birth of a rhinoceros resulting from artificial insemination (AI) with frozen and thawed semen.

Just after Americans have headed to the polls to elect their next president, a new report in the November 13th issue of Current Biology, a Cell Press publication, reveals how one species of fish picks its leaders: Most of the time they reach a consensus to go for the more attractive of two candidates.

When cockroaches flee their predators, they choose, seemingly at random, amongst one of a handful of preferred escape routes, according to a report published on November 13th in Current Biology, a Cell Press publication.

Despite the fact that household bleach is commonly used as a disinfectant, exactly how it works to fight bacteria remained an open question. Now, a report in the November 14th issue of the journal Cell, a Cell Press publication, provides an answer.

An unusual microorganism discovered in the open ocean may force scientists to rethink their understanding of how carbon and nitrogen cycle through ocean ecosystems. A research team led by Jonathan Zehr, professor of ocean sciences at the University of California, Santa Cruz, characterized the new microbe by analyzing its genetic material, even though researchers have not been able to grow it in the laboratory.

Scientists may have overcome a major hurdle to calculating how much carbon dioxide (CO2) is absorbed and released by plants, vital information for understanding how the biosphere responds to stress and for determining the amount of carbon that can be safely emitted by human activities. The problem is that ecosystems simultaneously take up and release CO2. The key finding is that the compound carbonyl sulfide, which plants consume in tandem with CO2, can be used to quantify gas flow into the plants during photosynthesis. The research is published in the November 14, issue of Science.

It has all the hallmarks of a Cretaceous melodrama. A dinosaur sits on her nest of a dozen eggs on a sandy river beach. Water levels rise, and the mother is faced with a dilemma: Stay or abandon her unhatched offspring to the flood and scramble to safety?

Researchers at the University of California, San Diego School of Medicine, led by Ajit Varki, M.D., have shown a new mechanism for how human consumption of red meat and milk products could contribute to the increased risk of cancerous tumors. Their findings, which suggest that inflammation resulting from a molecule introduced through consumption of these foods could promote tumor growth, are published online this week in advance of print publication in the Proceedings of the National Academy of Sciences (PNAS).

Prolonged exposure to cigarette smoke can increase levels of the stress hormone norepinephrine and enzymes in the heart that have the potential to reshape the left ventricle, according to new research at the University of Illinois at Chicago.

A previously unknown regulatory step during human immunodeficiency (HIV) replication provides a potentially valuable new target for HIV/AIDS therapy, report researchers at the Salk Institute for Biological Studies and the University of Wisconsin, Madison.