AncestryDNA: Shared matches
The matches that you share with your AncestryDNA "cousin" can help you work out the common ancestors between you and the "cousin". BUT it's important to understand that all AncestryDNA is reporting is that the shared march is appealing on both your match list and the AncestryDNA "cousin's" match list. You can ONLY see which matches you share with 4th cousins and closer. So you must share 20cM or more with your AncestryDNA "cousin" and the shared match and the AncestryDNA "cousin" must share 20cM or more with the shared match. Here's an example from my only match list. I share 31cM of DNA with Bill. He's my 3C1R on my maternal M7 Clancy and M8 Flaven lines. All our shared matches are on that line except Robyn. I share 43cM of DNA with Robyn. She's my 4C on paternal P5 Gersbach line. When I look at my shared matches with Robyn, apart from Bill, they are on my paternal P5 Gersbach line. Here's my