Wild Caribbean reef fish anywhere in the Caribbean. The final island to be featured is Trinidad, cut off from South America by rising sea levels 2,000 years ago. Its island fauna include many mainland species such as red howler monkeys, capuchins and scarlet ibis. Coral reefs, which thrive in the warm, shallow waters around Caribbean Islands, are the subject of the second programme. Hard corals are the reef-builders, and grow their tough external skeletons by extracting nutrients from algae growing within them. Time-lapse footage shows coral polyps emerging at night to trap drifting plankton. Marine life featured includes Caribbean reef squid, octopus
Mannar Island Mannar Island Mannar Island (; ) formerly spelt Manar Island, is part of Mannar District, Sri Lanka. It is linked to the main island of Sri Lanka by a causeway. It has an area of about 50 square kilometres, mainly covered with vegetation and sand. Adam's Bridge ( "āthām pālam"), is a chain of limestone shoals, between Pamban Island, also known as Rameswaram Island, off the southeastern coast of Tamil Nadu, India, and Mannar Island, off the northwestern coast of Sri Lanka. Geological evidence suggests that this bridge is a former land connection between India and Sri Lanka. Between 1914