Researchers have unearthed the planet's oldest-known intact biological macromolecules, microscopic bits of cellulose from 253-million-year-old salt deposits in the southwestern United States.
The remarkable preservation of the material suggests that under the right conditions, cellulose could last more than 1 billion years. Such a long-lived molecule, a chain of simple sugars, might give scientists searching for past extraterrestrial life on other planets a new target.
Cellulose, best known as the tough material in trees, shrubs, and grasses, is one of the most abundant biological materials on Earth. Altoget