Scientists created the world’s most significant family tree mapping the lives of almost 13 million people that spans 11 generations. It is considered a massive scientifically validated family tree based on publicly available data, according to the researchers.
The discovery described in the journal Science reveals something about the past of the humanity that includes their marriage and death. Yaniv Erlich, a data scientist and computational biologist at the New York Genome Center and his colleagues, led the research, according to National Geographic.
In the research, the team gathered 86 million publicly available profiles from the ancestry site Geni.com. They assessed them for any strange details including people who were both the parent and a child of another individual.
The researchers saw some small family trees and ended up with 5.3 million trees, the largest of which was the 13-million-people set, of whom 85 percent were from the North America and Europe, who lived between 1650 and 2000, according to Science Alert.
The researchers examined data looking for details from patterns of longevity and intermarriage to migration and genetic relationships. They discovered that genetics might play a smaller role in longevity as some scientists previously thought.
They also found that advances in transport technology harmonized with longer migrations. This referred to people born before 1800 looked for partners within an eight kilometers radius than the average of 19 kilometers by 1850 and a 100-kilometer radius by 1950.
The data also reveals that from 1650 to the start of the 19th century, the average married couple was fourth cousins. Joanna Kaplanis, one of the researchers from the Wellcome Trust Sanger Institute in Cambridge, UK, said that although people started to be born further away from their families during the early 19th century, they were still marrying cousins for 50 years. On the other hand, she also said that it seems the eventual decrease in inbreeding was more to do with cultural influences and just became less socially acceptable, as noted by the New Scientist.
The massive family tree also reveals something about longevity, which refers to genes that could help people live longer. In the previous studies, they indicated that lifespan is at least somewhat heritable. However, this new study found that genetics contributes to only 16 percent of what is necessary to see old age.
Currently, this vast family tree is publically available. Erlich is encouraging other researchers to take advantage of the resource to unlock some genealogical and scientific questions.