A Y-Chromosome Signature of Hegemony in Gaelic Ireland

[Gil]

A Y-Chromosome Signature of Hegemony in Gaelic Ireland

Laoise T. Moore et al.

Seventeen-marker simple tandem repeat genetic analysis of Irish Y chromosomes reveals a previously unnoted modal haplotype that peaks in frequency in the northwestern part of the island. It shows a significant association with surnames purported to have descended from the most important and enduring dynasty of early medieval Ireland, the Uí Néill. This suggests that such phylogenetic predominance is a biological record of past hegemony and supports the veracity of semimythological early genealogies. The fact that about one in five males sampled in northwestern Ireland is likely a patrilineal descendent of a single early medieval ancestor is a powerful illustration of the potential link between prolificacy and power and of how Y-chromosome phylogeography can be influenced by social selection.

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Which roughly means that a handful of irish are indeed the "fathers" of the modern day irish and genetic homogeneity is prevalent.
I haven't read anything about medieval Ireland which chronicles how man-woman relations were (absence or prevalence of monogamic/polygamic relations, etc), perhaps Milesian could point me some good texts.