Synthesizing reams of data from its three previous reports, the United Nations Intergovernmental Panel on Climate Change for the first time specifically points out important risks if governments fail to respond: melting ice sheets that could lead to a rapid rise in sea levels and the extinction of large numbers of species brought about by even moderate amounts of warming, on the order of 1 to 3

The Arctic ice cap shrank so much this summer that waves briefly lapped along two long-imagined Arctic shipping routes, the Northwest Passage over Canada and the Northern Sea Route over Russia.

Hundreds of feet below ground, the primary water source for this provincial capital of more than two million people is steadily running dry. The underground water table is sinking about four feet a year. Municipal wells have already drained two-thirds of the local groundwater.

Until now, scientists had found only the skulls of small-brain individuals at the Georgian site of Dmanisi. They said the new evidence apparently showed the anatomical capability of this extinct population for long-distance migrations.

In the study of human origins, paleoanthropology stares in frustration back to a dark age from three million to less than two million years ago. The missing mass in this case is the unfound fossils to document just when and under what circumstances our own genus Homo emerged.

No country in history has emerged as a major industrial power without creating a legacy of environmental damage that can take decades and big dollops of public wealth to undo.

Blood sugar control is important in diabetes, specialists say. It can help prevent dreaded complications like blindness, amputations and kidney failure. But controlling blood sugar is not enough.

Indian glaciers are among the least studied in the world, lacking the decades of data that scientists need to deduce trends. Nevertheless, the nascent research offers a snapshot of the consequences of global warming for this country and raises vital questions about how India will respond to them.

Historians often assume that they need pay no attention to human evolution because the process ground to a halt in the distant past. That assumption is looking less and less secure in light of new findings based on decoding human DNA.

Since its humble beginnings as a single cell, life has evolved into a spectacular array of shapes and sizes, from tiny fleas to towering Tyrannosaurus rex, from slow-soaring vultures to fast-swimming swordfish, and from modest ferns to alluring orchids. But just how such diversity of form could arise out of evolution’s mess of random genetic mutations — how a functional wing could s