I'm recalling, perhaps incorrectly, that chimps are closest to humans.
In theory, we have evolved from similar social groupings.
Are there any studies on the diversity of ancestors (mitochondria) within such primate groupings? I'm not sure what I should be searching for (terms), much less who is doing work in the field.
I'm wondering if bands eventually end up with one ancestress (random attrition or fitness taking down the others), or if they routinely have more than one ancestral female line (ie: are able to maintain diversity over the long term).