A: A blood moon is a deep reddening of the moon caused by the Earth passing between the moon and the sun. During the period of the eclipse, light from the sun... Full Answer >
Sometimes, bones are the only accessible source of DNA, thanks to their structure, which preserves DNA comparatively well and for a long time. The main problems of DNA extraction from bones are DNA degradation due to environmental factors and the presence of soil-derived inhibitors like humus acids [1â10].
Previously, the oldest human DNA sequenced came from bones that were less than 120,000 years old. Meyer said stable temperatures in the cave helped preserve the mitochondrial DNA, and credited recent advances in gene-sequencing technology for establishing the basis for the new milestone.