Samoan Islands with black sand beaches. The highest peak is Mt. Silisili, on the island of Savai'i, one of the highest peaks in Polynesia at . The highest point in American Samoa is on Ta’u, Lata Mountain, at . The two large islands of Upolu and Savai'i in Samoa, are among the largest of Polynesian islands, at and , respectively, exceeded in size only by the two main islands of Fiji and the Hawaiian islands of Hawaiʻi and Maui. The island of Upolu is more populated than Savai'i. The next largest island is Tutuila, where the city and harbor Pago Pago (population
Endemism in the Hawaiian Islands survive in the islands and whatever else was needed to reproduce. The narrowing of the gene pool meant that at the very beginning, the population of a colonizing species was a bit different from that of the remove, contributing population. Throughout time, the Hawaiian Islands formed linearly from northwest to the southeast. A study was conducted to determine the approximate ages of the Hawaiian Islands using K–Ar dating of the oldest found igneous rocks from each island. Kauai was determined to be about 5.1 million years old, Oahu about 3.7 million years old and the youngest island of Hawaii about