How to get from R to the R1a branch in the phylogenetic tree is covered here. How to get from "Adam" to R is covered in the yDNA Groupings page before this one. How a Family Branch identifies with a Haplogroup lower than R1a is covered in that family's yDNA Groupings page.
R1a is a large Haplogroup subclade more typically associated with Slavic people's. Hence the original R1a page here used in an admins study of his Slavic lines (now moved to R1a-Z280 Slavic). But a new member joined, a singlet that is R1a. Hence, recapturing this page for intended uses in this main surname study.
External References
- FTDNA Project for R1a
- Blog for R1a Project
- Facebook group for R1a
- Eupedia page on R1a
- Wikipedia page on R1a
- Haplomaps entry for R1a