Two warm-blooded mammal species have triumphed in the fast-paced environment of New York City: human beings and rats. Robert Sullivan was fascinated with how eager many people are to save whales or ...

A giant, critically endangered rat that makes the infamous rats of New York look like pet mice was caught on camera for the first time, researchers say. The Uromys vika giant rat is one of the world’s ...

A student discovers two new fossil remains of teeth in England that came from ancient mammals believed to be the earliest known ancestors of human beings. Grant Smith, an undergraduate student from ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to ...

These tooth models show the relative size comparison of a human tooth versus a rat tooth -- to give an idea of the technical challenges involved with performing dentistry on such a small scale. NOTE: ...

teeth, called a Rock Abrasion Tool (RAT). One RAT will ride on each of the twin Mars Exploration Rovers, launching to Mars in the summer of 2003. These RATS will allow humans to remotely "crack open" ...