After having focused on cave walls, researchers are now looking at the soil inside caves. For in the soil lie answers to questions about human and animal evolution. Using new techniques, researchers have been able to extract nuclear DNA – often referred to as the molecule of life because it contains genetic instructions for the development of all living organisms – from sediment samples.
Researchers have succeeded in mapping humans and animals that have inhabited many caves. In the Estatuas cave in Spain, they have genetically identified individuals who lived in the cave between 80,000 and 113,000 years ago, and have been able to determine both their sex and kinship patterns.
In the Chiquihuite Cave in Mexico, researchers found 12,000-year-old DNA from an extinct black bear. By comparing the DNA with that of modern bears, they discovered that descendants of cave bears moved as far north as Alaska in the US after the Ice Age.
The technology continues to evolve and who knows what else may be hiding inside these caves?