Galápagos tortoise

The Galápagos tortoise or Galápagos giant tortoise (Chelonoidis nigra) is the largest living species of tortoise. Modern Galápagos tortoises can weigh up to 417 kg (919 lb). Today, giant tortoises exist only on two remote archipelagos: the Galápagos 1000 km due west of Ecuador, and Aldabra in the Indian Ocean, 700 km east of Tanzania.

The tortoise is native to seven of the Galápagos Islands, a volcanic archipelago about 1,000 km (620 mi) west of the Ecuadorian mainland. With lifespans in the wild of over 100 years, it is one of the longest-lived vertebrates. A captive individual lived at least 170 years. Spanish explorers, who discovered the islands in the 16th century, named them after the Spanish galápago, meaning tortoise.

Shell size and shape vary between populations. On islands with humid highlands, the tortoises are larger, with domed shells and short necks; on islands with dry lowlands, the tortoises are smaller, with "saddleback" shells and long necks. Charles Darwin's observations of these differences on the second voyage of the Beagle in 1835, contributed to the development of his theory of evolution.

Tortoise

Tortoises (/ˈtɔːr.təs.ᵻz/) are a family, Testudinidae, of land-dwelling vertebrates in the order Testudines. Tortoises are shielded from predators by a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The carapace is fused to both the vertebrae and ribcage, and tortoises are unique among vertebrates in that the pectoral and pelvic girdles are inside, rather than outside, the ribcage. Tortoises can vary in size from a few centimeters to two meters. They are usually diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals.

Use of the terms turtle, tortoise, and terrapin

Differences exist in usage of the common terms turtle, tortoise, and terrapin, depending on the variety of English being used; usage is inconsistent and contradictory. These terms are common names and do not reflect precise biological or taxonomic distinctions.

The American Society of Ichthyologists and Herpetologists uses "turtle" to describe all species of the order Testudines, regardless of whether they are land-dwelling or sea-dwelling, and uses "tortoise" as a more specific term for slow-moving terrestrial species. General American usage agrees; turtle is often a general term (although some restrict it to aquatic turtles); tortoise is used only in reference to terrestrial turtles or, more narrowly, only those members of Testudinidae, the family of modern land tortoises; and terrapin may refer to turtles that are small and live in fresh and brackish water, in particular the diamondback terrapin (Malaclemys terrapin). In America, for example, the members of the genus Terrapene dwell on land, yet are referred to as box turtles rather than tortoises.

San Diego

San Diego /ˌsæn diːˈeɪɡoʊ/ (Spanish for "Saint Didacus") is a major city in California, on the coast of the Pacific Ocean in Southern California, approximately 120 miles (190 km) south of Los Angeles and immediately adjacent to the border with Mexico.

With an estimated population of 1,381,069 as of July 1, 2014, San Diego is the eighth-largest city in the United States and second-largest in California. San Diego is the birthplace of California and is known for its mild year-round climate, natural deep-water harbor, extensive beaches, long association with the U.S. Navy, and recent emergence as a healthcare and biotechnology development center.

Historically home to the Kumeyaay people, San Diego was the first site visited by Europeans on what is now the West Coast of the United States. Upon landing in San Diego Bay in 1542, Juan Rodríguez Cabrillo claimed the entire area for Spain, forming the basis for the settlement of Alta California 200 years later. The Presidio and Mission of San Diego, founded in 1769, formed the first European settlement in what is now California. In 1821, San Diego became part of newly independent Mexico, and in 1850, became part of the United States following the Mexican–American War and the admission of California to the union.

San Diego Zoo

The San Diego Zoo is a zoo in Balboa Park, San Diego, California housing over 3,700 animals of more than 650 species and subspecies. Its parent organization, San Diego Zoo Global, is the largest zoological membership association in the world, with more than 250,000 member households and 130,000 child memberships, representing more than a half million people. San Diego Zoo pioneered the concept of open-air, cageless exhibits that re-create natural animal habitats. It is one of the few zoos in the world that houses the giant panda. In 2013, the zoo added a new Koalafornia Adventure, providing an Australian experience.

It is privately operated by the nonprofit Zoological Society of San Diego on 100 acres (40 ha) of parkland leased from the City of San Diego, and ownership of all animals, equipment and other assets rests with the City of San Diego. The San Diego Zoo is an accredited member of the Association of Zoos and Aquariums (AZA) and the American Alliance of Museums (AAM), and a member of the Zoological Association of America (ZAA) and the World Association of Zoos and Aquariums (WAZA). San Diego Zoo Global also operates the San Diego Zoo Safari Park and the San Diego Zoo Institute for Conservation Research.