The document summarizes insular fauna, or animal life on islands. It discusses the differences between continental islands and oceanic islands. Continental islands, like Great Britain and Japan, were once connected to mainland but are now separated by water. Their fauna is similar to the mainland. Oceanic islands, such as Galapagos and Krakatoa, have never been connected and have unique fauna adapted to island conditions, often with flightless birds and giant reptiles. It also describes the ancient islands of New Zealand and Madagascar, which have relic species and a high proportion of endemic fauna.