in July 1978, with the government of Toaripi Lauti continuing as a caretaker government until the 1981 elections were held. Toaripi Lauti became the first Prime Minister on 1 October 1978, when Tuvalu became an independent nation. That date is also celebrated as the country's Independence Day and is a public holiday. Tuvalu became fully independent within the Commonwealth on 1 October 1978. On 26 October 1982, Queen Elizabeth II made a special royal tour to Tuvalu. On 5 September 2000, Tuvalu became the 189th member of the United Nations. On 15 November 2022, amidst sea level rises, Tuvalu announced plans as the first country in the world to build a self-digital replica in the metaverse in order to preserve its cultural heritage. Geography and environment Geography Tuvalu is a volcanic archipelago, and consists of three reef islands (Nanumanga, Niutao and Niulakita) and six true atolls (Funafuti, Nanumea, Nui, Nukufetau, Nukulaelae and Vaitupu). Its small, scattered group of low-lying atolls have poor soil and a total land area of only about making it the fourth smallest country in the world. The highest elevation is above sea level on Niulakita. Over four decades, there had been a net increase in land area of the islets of 73.5 ha (2.9%), although the changes are not uniform, with 74% increasing and 27% decreasing in size. The sea level at the Funafuti tide gauge has risen at 3.9 mm per year, which is approximately twice the global average. A 2018 report stated that the rising sea levels are identified as creating an increased transfer of wave energy across reef surfaces, which shifts sand, resulting in accretion to island shorelines. The Tuvalu Prime Minister objected to the report's implication that there were "alternate" strategies for Islanders to adapt to rising sea levels, and criticised it for neglecting issues such as saltwater intrusion into groundwater tables as a result of sea level rise. Funafuti is the largest atoll, and comprises numerous islets around a central lagoon that is approximately (N–S) by (W-E), centred on 179°7'E and 8°30'S. On the atolls, an annular reef rim surrounds the lagoon with seven natural reef channels. Surveys were carried out in May 2010 of the reef habitats of Nanumea, Nukulaelae and Funafuti; a total of 317 fish species were recorded during this Tuvalu Marine Life study. The surveys identified 66 species that had not previously been recorded in Tuvalu, which