How much the New World Spanish dialects owe to those of Spain has long been a subject for dispute among Hispanic scholars. Belief in the theory of Andalusian influence, based, as it is, largely upon seseo and yeísmo, has been seriously shaken by recent studies on the chronology and diffusion of these two phenomena, by more exact knowledge of the modern peninsular dialects, and by the hitherto available statistical studies on regional emigration to America. But though statistical counts tend to show that during the sixteenth century as a whole no single region contributed an over-all majority of colonists to the Indies, claims are still made that individual parts of the New World were first colonized chiefly by settlers from this or that region of Spain. For example, Andalusians and Extremefios are generally credited with a major part in the colonization of Peru, but so far actual figures are lacking either to confirm or refute this. Amado Alonso and Raimundo Lida, while rejecting the theory of the Andalusian origin of New World dialects in general, concede that Andalusians probably did predominate during the first 30 years in the Antilles. But Tomás Navarro, in his study of the Spanish of Puerto Rico, concurs with the belief of José Padín that that island's first settlers were principally colonists from Old Castile: again there have been no statistics.