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The tracks left by organisms are among the most difficult of fossils to interpret. But just such evidence puts debate about the origins of four-limbed vertebrates (which include ourselves) on a changed footing.
The peculiar ultra-fast trembling motion of a free electron — the Zitterbewegung predicted by Erwin Schrödinger in 1930 when he scrutinized the Dirac equation — has been simulated using a single trapped ion.
Retrieving a memory initiates a window of vulnerability for that memory. Simple behavioural methods can modify distressing memories during this window, eliminating fear reactions to traumatic reminders.
A survey of mammalian genomes has unexpectedly unearthed DNA derived from bornaviruses, leading to speculation about the role of these viruses in causing mutations with evolutionary and medical consequences.
