Manbun Beakers (Hunter and Woodward)

If you're wondering about the basis for certain interpretations of Beaker clothing and styles, here's the archaeological basis for manbuns as described in "Ritual in Early Bronze Age Grave Goods" by John Hunter and Ann Woodward.

In fact, this book has a wealth of information about the specific arguments for much of the Beaker dress, if you can find full access. 

Re-enactment from Jan Obleci Pra Cloveka

The placement of bone pins near the top or back of heads occurs only with men, but only in the later Beaker period or EBA.  Earlier, these pins appear at the waist, perhaps as a sort of fastener.  So it would almost appear that the fashion evolves a little over time.