Below are the top matches for a woman who is adopted. (I wrote in the amount of shared DNA from the screen shot.) The "second cousin" and "third cousin" share almost the same amount of DNA with her, so the designations may be misleading. In the "fourth cousin" category, we have someone who shares 64 cM, which is workable in an adoption case. The next top match shares only 28 cM over two segments, which really is not useful when we have no family tree.
Seeing the actual amount of shared DNA lets us know which matches will be more helpful as we try to construct this woman's family tree.
|The "third cousin" also participates at 23andMe.|
Ancestry still needs to reveal WHERE the shared segments are located. You can view this information at 23andMe and FamilyTreeDNA. (See this blog post for examples and why we need this information.)