Thebird flu, so-called H5N1, has top epidemiologists across the world on edge because of its potential to mutate into a new strain that no one would be immune to and that could easily spread among humans.
That status was called into question two years ago by Chinese scientists, who proposed yanking it off the"bird" branch of the evolutionary family tree and moving it onto a closely related lineage of birdlike dinosaurs.
Palaeogeneticists at the University of Copenhagen and Michael Bunce at Murdoch University in Perth, Australia determined the half-life after studying a set of 158 DNA-containing bones from an extinct species of birdcalled "moa" (a feat in and of itself).