and given names Fewer than a hundred Sardinian surnames are needed to group together as much as a third of the whole Sardinian population. The most common Sardinian surnames, like Sanna (fang), Piras (pears), Pinna (feather, pen) and Melis (honey), derive from the Sardinian language and developed among the Judicates in the Middle Ages as a result of being registered in documents like the condaghes for administrative purposes; most of them derive either from Sardinian place names (e.g. Fonnesu "from Fonni", Busincu "from Bosa" etc.), from animal names (e.g. Porcu "pig", Piga "magpie", Cadeddu "puppy" etc.) or from a person's occupation, nickname (e.g. Pittau "Sebastian"), distinctive trait (e.g. Mannu "big"), and filiation (last names ending in -eddu which could stand for "son of", e.g. Corbeddu "son/daughter of Corbu"); a number of them have undergone Italianization over the most recent centuries (e.g. Pintori, Scano, Zanfarino, Spano, etc.). Some local surnames also derive from terms of the Paleo-Sardinian substrate. The largest percentage of last names originating from outside the island is from Southern Corsica (like Cossu, Cossiga, Alivesi and Achenza, originally from the towns of Olivese and Quenza respectively), followed by Italian (especially Piedmontese but also Campanian, Sicilian and Ligurian, originating from the days of the Savoyard rule and the assimilation policy: some of them have been "Sardinianized", like Accardu, Calzinu, Gambinu, Raggiu, etc.) and Spanish (especially Catalan) surnames. The Sardinian personal names (like Baínzu or Gavine "Gavin", Bachis "Bachisius", Bobore "Salvator", Iroxi "George", Chìrigu "Cyricus", Gonare "Gonarius", Elianora "Eleanor", Boele "Raphael", Sidore "Isidore", Billía "William", Tiadora "Theodora", Itria, etc.) are historically attested and were common among the islanders up until the contemporary era, when they switched in full measure to the Italian names. Self-identification Population surveys have been carried out, on repeated occasions, to provide information about the Sardinians' identity, as well as their conciliation with the institutional layers of political governance. The most detailed survey, conducted by the University of Cagliari and Edinburgh, made use of a Moreno Question which gave the following results: (1) just Sardinian, 26%; (2) more Sardinian than Italian, 37%; (3) equally Sardinian and Italian, 31%; (4) more Italian than Sardinian, 5%; (5) only Italian and not Sardinian, 1%. A 2017 poll by the Ixè Institute reported that 51% of the Sardinians questioned identified themselves as Sardinian (as opposed to an Italian average of 15% who identified by their region of origin) rather than Italian (19%),