Oceanian realm

Conversely, New Guinea, New Caledonia, the Solomon Islands and New Zealand are included in the Oceanian realm in the classification scheme developed by Miklos Udvardy in 1975.

[4] Despite only being a few hundred miles removed from the South American coast, the islands have strong Hawaiian and southeast Polynesian biogeographic influences, and the presence of an endemic insect and plant family.

While other realms include old continental land masses or fragments of continents, Oceania is composed mostly of volcanic high islands and coral atolls that arose from the sea in geologically recent times, many of them in the Pleistocene.

Other plants, notably coconut palms and mangroves, produce seeds that can float in salt water over long distances, eventually washing up on distant beaches, and thus Cocos trees are ubiquitous across Oceania.

Certain types of animals that are ecologically important on the continental realms, like large land predators and grazing mammals, were entirely absent from the islands of Oceania until humans brought them.

A number of islands have indigenous lizards, including geckoes and skinks, whose ancestors probably arrived on floating rafts of vegetation washed out to sea by storms.

From the seventeenth century onwards European settlers brought other animals, including cats, cattle, horses, small Asian mongoose (Herpestes javanicus), sheep, goats, and the brown rat (Rattus norvegicus).

More recently, Guam's native bird and lizard species were decimated after the introduction of the brown tree snake (Boiga irregularis) in the 1940s.