Molecular studies have reported divergence times of modern placental orders long before the Cretaceous--Tertiary boundary and far older than paleontological data. By accounting for complex evolution of mitochondrial genome, scientists obtained a much younger time at the root of placental mammals, 84 million years ago instead of around 122 million years ago.

We have usually quite strong memories of past events like an exciting holiday or a pleasant birthday party. However it is not clear how the brain keeps track of the temporal sequence in such memories: did Paul spill a glass of wine before or after Mary left the party? A research group has now provided evidence that sleep not only strengthens the content of a memory but also the particular order in which they were experienced.

Mayo Clinic researchers have designed a new strategy in the promising field of cancer vaccine research that's proven to be successful in boosting T cells -- the immune builders akin to a super defense force against cancer cells.

Magnetic shields like those used in could one day keep astronauts on long-haul missions safe from dangerous radiation