Lizards gave rise to legless snakes. Cave fishes don’t have eyeballs. In evolution, complicated structures often get lost. Dollo’s Law states that complicated structures can't be re-evolved because the genes that code for them were lost or have mutated. A group of sea snails breaks Dollo’s law, Rachel Collin, Staff Scientist at the Smithsonian Tropical Research Institute and colleagues from two Chilean universities announce in the April, 2007, Biological Bulletin.

Astronomers have discovered the most Earth-like planet outside our Solar System to date, an exoplanet with a radius only 50% larger than the Earth and capable of having liquid water. Using the ESO 3.6-m telescope, a team of Swiss, French and Portuguese scientists discovered a super-Earth about 5 times the mass of the Earth that orbits a red dwarf, already known to harbour a Neptune-mass planet. The astronomers have also strong evidence for the presence of a third planet with a mass about 8 Earth masses.

Parents-to-be might soon don 3-D glasses in the ultrasound lab to see their developing fetuses in the womb "in living 3-D, just like at the IMAX movies," according to researchers at Duke University's Pratt School of Engineering.

The same Duke team that first developed real-time, three-dimensional ultrasound imaging says it has now modified the commercial version of the scanner to produce an even more realistic perception of depth. Paired images seem to pop out of the screen when viewed with the special glasses.

An independent study group, convened by AAAS’s Center for Science, Technology and Security Policy, has issued a report on the proposed Reliable Replacement Warhead (RRW) and its role in the future U.S. nuclear weapons program.

The panel concluded that most of the anticipated benefits of the proposed RRW program -- more easily maintained nuclear weapons with enhanced performance margins, improved safety and security properties, and greater ease of manufacture -- would occur in the long term subsequent to modernization of the weapons production complex.

Findings described in a new study by Stanford scientists may be the first step toward a major revolution in human regenerative medicine—a future where advanced organ damage can be repaired by the body itself. In the May 2007 issue of The FASEB Journal, researchers show that a human evolutionary ancestor, the sea squirt, can correct abnormalities over a series of generations, suggesting that a similar regenerative process might be possible in people.

Obese and overweight children increase their food intake by more than 100% after watching food advertisements on television; a study by the University of Liverpool psychologists has shown.

A group of 60 children of varying weights, aged between nine and eleven years was shown a series of both food television adverts and toy adverts, followed by a cartoon. Food intake following the food adverts was significantly higher compared with the toy adverts in all weight groups, with the obese children increasing their consumption by 134%; overweight children by 101% and normal weight children by 84%.