This may be needed as transition between the ancient Iberian genetic data of Valdiosera and Günther that I discussed two days ago and the modern Iberian genetic data that I'm planning to discuss very soon (just chewing on the data, because it is a bit perplexing in some aspects, but ref. Bycroft 2018 if you want to peek on it on your own).
|Fig. 1B from Valdiosera, Günther et al. 2018, annotated by me.|
Just that: we see very clearly how ancient Iberians were at the beginning of Neolithic like modern Sardinians and by the time of Chalcolithic in some cases and at the Bronze Age everywhere, they had turned into something like modern Basques, i.e. more Paleoeuropean but not yet more Indoeuropean at all.
Modern Spaniards/Iberians seem to be mostly that Basque-like Bronze Age base plus some Indoeuropean admixture from either the continent (Celts surely) or Italy (Romans no doubt).
Maybe it is like stating the obvious but the obvious is not always obvious for everyone and understanding this will be handy when dealing with modern Iberian DNA and its structure.