Question

Three distinct lines of genetic evidence for our of Africa model is _____?

Answer 1

The Out of Africa model is supported by genetic evidence from mitochondrial DNA tracing back to a common ancestor in Africa 160,000 years ago, Y chromosome lineage from Africa 140,000 years ago, and the highest genetic diversity found in Africa.

Step-by-step explanation:

Out of Africa Model and Genetic Evidence

The Out of Africa model of human evolution posits that modern humans originated in Africa and then dispersed to other parts of the world. This model is supported by three lines of genetic evidence:

1. Analysis of mitochondrial DNA (mtDNA) shows that all modern humans can trace their matrilineal descent back to a common ancestor who lived in Africa approximately 160,000 years ago.
2. Evidence from the study of the Y chromosome indicates that all men have inherited their Y chromosome from a male who lived in Africa around 140,000 years ago.
3. Genetic diversity is highest in Africa, suggesting it is the oldest established human population. The allele for sickle-cell anemia, found in African descendants in the Western Hemisphere, is believed to have originated in West Africa.

These findings provide a strong genetic foundation for the Out of Africa model, showing that genetic variance found in Africa is also present around the world, but there are variances in Africa not found elsewhere, indicating a single point of origin for modern humans.