Coral Bleaching

Environmental stresses can cause irreparable harm to coral reefs. Unusually high seawater temperatures may be a principal culprit

How the Milky Way Formed

Its halo and disk suggest that the collapse of a gas cloud, stellar explosions and the capture of galactic fragments may have all played a role

Carbohydrates in Cell Recognition

Telltale surface sugars enable cells to identify and interact with one another. New drugs aimed at those carbohydrates could stop infection and inflammation

The Earliest History of the Earth

Radioactive dating techniques have illuminated vast stretches of geologic history, bringing the most ancient eras of the earth's evolution into view

Madagascar's Lemurs

These primates can tell us a great deal about our own evolutionary past. But many species are already extinct, and the habitats of those that remain are shrinking fast

Quantum Dots

Nanotechnologists can now confine electrons to pointlike structures. Such “designer atoms” may lead to new electronic and optical devices

The Mind and Donald O. Hebb

By rooting behavior in ideas, and ideas in the brain, Hebb laid the groundwork for modern neuroscience. His theory prefigured computer models of neural networks

Adapting to Complexity