Where have we Mitchells been for the last 5,000 years?

Where have we Mitchells been for the last 5,000 years?

I have been trying to understand our history as an ancient family. It isn't easy, because I didn't major in science and I don't understand the languages of science. I am a word-person not a number person. I recently asked a question on the RL-21 DNA Project website. I asked them to explain it to me in words since, even though I have been following the discussion on the website, I don’t understand the spreadsheets and scientific jargon that I read there. I said to those experts, “I need words.”

My Question: My closest (Mitchell) match on FTDNA (25/37) is a Basque gentleman. We have been trying to figure out when we last were sitting around the same campfire. I guess it was before L 21 and before there were Basques. Can you explain our history to me?

This is the answer I received and it is a good one:

Answer: [A couple of notes: First, the Bell Beaker culture may have built Stonehenge. That is the prevailing view at this time. Second, the term MRCA means Most Recent Common Ancestor.” Sally]

"Suppose the Bell Beaker Folk were derived from a population that expanded out of the Caucasus with the knowledge of mining and working copper. They might keep this secret to themselves since an advanced technology might give them an advantage over any other populations they might encounter. They might also just be unreceptive to different cultural practices and thus keep to themselves and intermarry. If they found themselves in northern France about 2,200 B.C. they might form a homogeneous population where most of the members shared a restricted pool of autosomal [DNA] values. As the population grew, a segment might choose to branch off in search of new land to farm or sources of copper ore to work. Suppose such a segment moved south into southeastern France and then to the area of the Pyrenees. Groups living in mountain valleys would have geography to assist them in the social isolation they practiced with respect to surrounding populations. Suppose that the L21 mutation occurred in the original Beaker population located in northern France right about the time a group moved south, so that the southern group did not include any L21 members. Or suppose L21 evolved in a group that was socially isolated from the population that moved south, in which case it may have existed for many generations and already have started to spread east and west when the ancestors of the Basques began migrating. If the original populations, or elements of these populations, continued to exercise social isolation from other populations they would retain roughly similar pools of autosomal [DNA] marker values. This might result in people whose ancestry has lived in the British Isles for the last 3,000 years showing autosomal [DNA], and perhaps yDNA, results similar to Basque populations, or some Roma populations, or some Ashkenazi populations, or some ethnic groups from Pakistan, or India, etc. etc. Or maybe not. Based on our current knowledge it could have happened like that, but just because something could have happened doesn't mean that it did." by Ralph Porter.