Humans develop sharp vision during early fetal development thanks to an interplay between a vitamin A derivative and thyroid hormones in the retina, Johns Hopkins University scientists have found.

An earthquake typically sets off ruptures that ripple out from its underground origins. But on rare occasions, seismologists have observed quakes that reverse course, further shaking up areas that ...

The tiny shell protecting the HIV virus resembles a slightly rounded ice cream cone, but there is nothing sweet about it. More than 40 million people worldwide live with AIDS because of this virus, ...