Amber Y.

March 8, 2017

Ancient DNA Yields Unprecedented Insights Into Mysterious Chaco Civilization

Just over a hundred and twenty years ago (1896) archeologists uncovered a 650 room multi story brick home in Chaco Canyon New Mexico that was named Pueblo Bonita. This culture is believed to have flourished between A.D. 800-1250. There were at least 12 huge homes similar to Pueblo Bonita spanning the four corners; New Mexico, Arizona, Colorado, and Utah. Continued study of these dwellings and further diggings concluded that most Chaconean’s lived in smaller homes surrounding the grand homes like Pueblo Bonita. Buried deep below the Pueblo Bonita was a burial room of past leaders’ remains and belongings. Scientist discovered something very interesting; a matrilineal dynasty spanning over 330 years. Matrilineal meaning inheriting or determining descent through the female line. 

This matrilineal dynasty was discovered through the extraction of mitochondrial DNA extracted from the ancient remains. As we have learned in class recently, the mitochondria are organelles found in large numbers in most cells. In which the biochemical processes of cellular respiration and energy production occur. Mitochondrial DNA is an extranuclear double stranded DNA found exclusively in mitochondria that in most Eukaryotes is a circular molecule and is maternally inherited only. 

Researchers working on this project  experienced unheard of results when all sequenced mitochondrial DNA from 9 individuals placed in chronological sequence and resulted an average of 98%. All 9 sequences were identical, which almost never happens. What this means is that each generation descended from the same original maternal ancestor. As further study, researchers also sequenced nuclear DNA from 6 different burials. and found that there was a set of mother-daughter and grandmother, grandson relationships. Nuclear DNA  can comes from both the mother and the father DNA donors. 

This topic has been intriguing to expand on. As you know, we just learned in class about DNA and the Mitochondria and its role in Cellular respiration. Biology is a fun class to learn the material. I think that it is really amazing how applicable the lessons from our biology class are in real life. Also, I find it very interesting how dating of the remains is done mostly from  radiometric dating or radioactive dating which means that isotopes with a short half  life won’t work to date dinosaurs. Being that I am a woman, it is interesting to learn from other cultures  how society was and how religious or political leadership roles were carried out. Of course that aspect is just left to speculation and logical observation and reasoning.