structural:expansion
History

A small number of alleged hypogea (underground structures carved into rocks) have been identified on the islands of Corvo, Santa Maria, and Terceira by Portuguese archaeologist Nuno Ribeiro, who speculated that they might date back 2,000 years, implying a human presence on the island before the Portuguese. These structures have been used by settlers in the Azores to store grain and the suggestion by Ribeiro that they might be burial sites is unconfirmed. Detailed examination and dating to authenticate the validity of these speculations is lacking; thus it is unclear whether these structures are natural or human-made and whether they predate the 15th century Portuguese colonization of the Azores.

According to a 2015 paper published in Journal of Evolutionary Biology, research based on mouse mitochondrial DNA points to a Scandinavian rather than Portuguese origin of the local mouse population. A 2021 paper published in Proceedings of the National Academy of Sciences, using data from lake sediment core sampling, suggests brush-clearing was undertaken and animal husbandry introduced between 700 and 850 A.D. These findings suggest a brief period of Norse settlement, and the 2021 paper further cites climate simulations that suggest the dominant winds in the North Atlantic Ocean in that period blew from the northeast, which would have taken Viking ships heading southwest from Scandinavia more or less directly to the Azores.