Читать книгу Oahu Trails. Walks Strolls and Treks on the Capital Island онлайн

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Then, about 1.1 million years ago, a period of secondary, cone-building eruptions began on southeast Oahu. By the time it ended some 31,000 years ago, it had left cones that are some of Oahu’s most famous landmarks: Diamond Head, Koko Head, Koko Crater, and Hanauma Bay, to name a few. Is it all over now? No one can be sure. There is circumstantial evidence that an undersea eruption may have occurred between Oahu and Kauai in 1956. In the meantime, however, erosion prevails on Oahu, changing the landscape constantly.

Life arrives

Living organisms colonize new land rapidly. In Hawaii, plants established themselves once there was a little soil for them. Seeds arrived on the air currents, or floated in on the sea, or hitched a ride on the feathers or in the guts of birds. Insects and spiders also took advantage of the air currents. Birds were certainly among the first visitors. Living things found little competition and quickly adapted to their new home, evolving into an astonishing variety of species many of which occur naturally only on the Hawaiian Islands (“endemic to Hawaii”). The only mammals to arrive were the bat and the seal. Some birds became flightless—a fairly common adaptation on isolated islands with no ground predators.