Cancer is a disease of mutations. Tumor cells are riddled with genetic mutations not found in healthy cells. Scientists estimate that it takes five to 10 key mutations for a healthy cell to become cancerous.

Some of these mutations can be caused by assaults from the environment, such as ultraviolet rays and cigarette smoke. Others arise from harmful molecules produced by the cells themselves. In recent years, researchers have begun taking a closer look at these mutations, to try to understand how they arise in healthy cells, and what causes these cells to later erupt into full-blown cancer.

Continue reading “Researchers Explore a Cancer Paradox” →

In a rare political riposte, Senator Elizabeth Warren on Monday released an analysis of her DNA indicating that she has a Native American ancestor, likely between six and 10 generations back in her family history.

President Trump has mocked Ms. Warren’s claims of Native American ancestry, often calling her Pocahontas. The new analysis appeared to be scientifically rigorous, researchers said, but it cannot give someone a cultural identity as Native American.

The research on Ms. Warren’s DNA was led by Carlos Bustamante, a Stanford University geneticist who has written a number of studies on the genetic ancestry of people in the Americas. The results were first reported by the Boston Globe.

Continue reading “Elizabeth Warren Has a Native American Ancestor. Does That Make Her Native American?” →

Forests have burned in spectacular fashion this year. From California to Colorado, Portugal to Greece, photographers have captured terrifying images of infernos soaring into the sky and spreading to the horizon.

The fires left scenes of ashen destruction, but they did not wipe out everything. Scattered about the ravaged landscapes were islands of trees, shrubs and grass that survived unharmed.

It’s easy to overlook these remnants, which ecologists call fire refugia. But they can be vital to the long-term well-being of forests. These havens shelter species that are vulnerable to fires. Afterward, they can be starting points for the ecosystem’s regeneration.

Continue reading “‘Lifeboats’ Amid the World’s Wildfires” →