As you can see, I have a 100% Senegalese paternal match sharing 8 cM with 1 segment and it's the same unweighted too. So question is what era/generation is our recent common ancestor? As you can also see, I have 4% Senegalese genome contribution all from my paternal side. I'm Black American as many who are regulars post here.
There was a thread earlier that asked about how a person could be 80% African and 20% European genome contribution be "Black" but another person who has 80% European and 20% African genome contribution be "mixed" and not "White?" To me, it's a fundamental issue of what I see in discussions like this often.
For example, commercial genealogists "teach" about how much dna we receive from our ancestors whether it's parents, grandparents, great grandparents, 2nd great grandparents, 3rd great grandparents, and etc. That's sound teaching on the surface because it helps us with finding where our ancestors originated from.
But even with established rules like this, there are going to be exceptions to this. For instance, according to AncestryDNA, my genetic makeup is 79% "African," 21% "European," and 1% "Indigenous American" but there's nuance in my genetic makeup as I'm a 4th-5th generation full descendant of The 1860 4.4 million Black American population, which before The US Civil War had nearly 4 million under the yoke of US Chattel Slavery and nearly 500 thousand free under the social constructed caste system of American racism exemplified in the category of American Blackness.
So because of this, I have no frame of reference for Nigeria or Cameroon or Ghana or Benin or Central Scotland and Northern Ireland or North East England or Yucatan Peninsula. I can't say, "I'm 32% Nigeria because this comes from a grandparent who's from present day Nigeria." It's literally from the multi generational genotypic expression within being a full descendant of The 1860 4.4 million Black American population. I have long ancestral history in the United States, at least 10 generations, and so my genetic makeup is the revelation of having a deep rooted American history as a full descendant of The 1860 4.4 million Black American population.
But an even better example are those who have Latin American ancestry. Latin Americans are even more multi generational "admixed" than Black Americans like me are. So whatever percentage of "Indigenous to the Americas," Iberian Peninsula(Spain, Portugal, Canary Islands)", "Sephardic Jewish," or "North Africa," you're not going to find verify ancestors from those areas because none of this is from recent ancestors. It's all of the history of your ancestors in those Latin American countries.
I'm not saying that taking dna tests are a waste of time. The best part of taking dna matches is using the DNA matches we get which leads us to more knowledge about our genealogical research. That's why I took AncestryDNA over 6 years ago. I was adopted at 9 years old, in the foster care system from 5 years old. From taking AncestryDNA, I matched a paternal aunt which over time, I was able to reconnect with my biological father after 40 years. From this, I was able to confirm my ancestral history on both sides of my family and I have a family tree that I have verification to at least 3rd great grandparents which is a big deal if you're a descendant of The 1860 4.4 million Black American dealing with "The 1870 Brick Wall" that happens because of having enslaved ancestors who weren't named in records until after 1865.
So before anyone say TL:DR, what I hope to do with this post is get us to be flexible and pen minded on what we see within our dna results, don't use your results as "tools" to "identify from," there are other tools like dna journeys which aren't perfect but are usually pretty helpful because it comes from the network of matches that we have as a tool for genealogical research.