Las Vegas, Nevada; Mirage Hotel; Sigfried and Roy's Secret Garden; July 17, 2008.
From Wikipedia: Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 metres (4 ft) and 40 kilograms (88 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and ten tonnes (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture. Dolphins are often regarded as one of Earth's most intelligent animals, though it is hard to say just how intelligent dolphins are, as comparisons of species' relative intelligence are complicated by differences in sensory apparatus, response modes, and nature of cognition. Furthermore, the difficulty and expense of doing experimental work with large aquatics means that some tests which could yield meaningful results still have not been carried out, or have been carried out with inadequate sample size and methodology. Dolphin behaviour has been studied extensively by humans however, both in captivity and in the wild. See the cetacean intelligence article for more details. Dolphins are social, living in pods (also called "schools") of up to a dozen individuals. In places with a high abundance of food, pods can join temporarily, forming an aggregation called a superpod; such groupings may exceed a thousand dolphins. The individuals communicate using a variety of clicks, whistles and other vocalizations. They also use ultrasonic sounds for echolocation. Membership in pods is not rigid; interchange is common. However, the cetaceans can establish strong bonds between each other. This leads to them staying with injured or ill individuals, even actively helping them to breathe by bringing them to the surface if needed. This altruistic behaviour does not appear to be limited to their own species however. A dolphin in New Zealand that goes by the name of Moko has been observed to seemingly help guide a female Pygmy Sperm Whale together with her calf out of shallow water where they had stranded several times. They have also been known to seemingly protect swimmers from sharks by swimming circles around the swimmers. Dolphins also show cultural behaviour, something long believed to be a quality unique to humans. In May 2005, a discovery was made in Australia which shows this cultural aspect of dolphin behaviour: Some dolphins, such as the Indo-Pacific Bottlenose Dolphin (Tursiops aduncus) teach their young to use tools. The dolphins break sponges off and cover their snouts with them thus protecting their snouts while foraging. This knowledge of how to use a tool is mostly transferred from mothers to daughters, unlike simian primates, where the knowledge is generally passed on to both sexes. The technology to use sponges as mouth protection is not genetically inherited but a taught behaviour. Another such behaviour was discovered amongst river dolphins in Brazil, where some male dolphins apparently use objects such
