iAldabra Giant Tortoise
Conservation status
Vulnerable (VU)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Order: Testudines Suborder: Cryptodira Family: Testudinidae Genus: Geochelone Species: G. gigantea
Binomial name
Geochelone gigantea Schweigger, 1812

The Aldabra Giant Tortoise (Geochelone gigantea), from the islands of the Aldabra Atoll in the Seychelles, is one of the largest tortoises in the world. Similar in size to the famous Galapagos Giant Tortoise, its carapace averages 120 cm (47 inches) in length. The average weight of a male is around 250 kg (551 pounds), but one male at the Fort Worth Zoological Park weighs over 360 kg (793 pounds). This species is widely referred to as Geochelone gigantea but is now placed in the genus Dipsochelys (or sometimes in the invalid genus Aldabrachelys) as Dipsochelys dussumieri. Aldabra Giant Tortoise (Dipsochelys dussumieri) from Aldabra atoll in the Seychelles, at Bristol Zoo, Bristol, England. ... The conservation status of a species is an indicator of the likelihood of that species continuing to survive. ... Image File history File links Status_iucn2. ... A vulnerable species is one whose chances of extinction characterize it as threatened but not quite as endangered. ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Subregnum Parazoa Porifera Subregnum Eumetazoa Placozoa Orthonectida Rhombozoa Radiata (unranked) Ctenophora Cnidaria Bilateria (unranked) Acoelomorpha Myxozoa Superphylum Deuterostomia Chordata Hemichordata Echinodermata Chaetognatha Superphylum Ecdysozoa Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Onychophora Tardigrada Arthropoda Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Sipuncula Nemertea Phoronida Bryozoa Entoprocta Brachiopoda... Typical Classes Subphylum Urochordata - Tunicates Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Orders Procolophonia (extinct) Testudines Araeoscelidia (extinct) Avicephala (extinct) Younginiformes (extinct) Sauropterygia Ichthyosauria (extinct) Placodontia (extinct) Nothosauria (extinct) Plesiosauria (extinct) Sphenodontia Squamata Prolacertiformes (extinct) Archosauria Crurotarsi Order Aetosauria Order Phytosauria Order Rauisuchia Order Crocodilia Ornithodira Pterosauria (extinct) Marasuchus (extinct) Dinosauria (extinct) Order Saurischia Order Ornithischia Reptiles are tetrapods and amniotes, animals... Suborders Cryptodira Pleurodira See text for families. ... Most modern turtles and tortoises belong to this group. ... For the band, see Tortoise (band). ... Species G. carbonaria G. elegans G. gigantea G. nigra G. pardalis G. platynota G. radiata G. sulcata Geochelone is a genus of tortoises. ... In biology, binomial nomenclature is the formal method of naming species. ... Map of Aldabra Atoll Aldabra and Assumption Island Aldabra Atoll Aldabra is a raised coral atoll in the Indian Ocean virtually untouched by humans, with distinctive island fauna, including the Aldabra Giant Tortoise. ... Genera Chersina Dipsochelys Furculachelys Geochelone Gopherus Homopus Indotestudo Kinixys Malacochersus Manouria Psammobates Pyxis Testudo A tortoise is a land-dwelling reptile of the order Testudines. ... Binomial name Geochelone nigra (Quoy & Gaimard, 1824) Synonyms Geochelone elephantopus (Harlan, 1827) The Galápagos tortoise (or Galápagos giant tortoise), is the largest living tortoise, endemic to nine islands of the Galápagos archepelago. ... The term carapace refers to a dorsal section of an exoskeleton or shell, in a number of animal groups. ... This article is being considered for deletion in accordance with Wikipedias deletion policy. ... Mid-19th century tool for converting between different standards of the inch An inch is an Imperial and U.S. customary unit of length. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ... The pound is the name of a number of units of mass, all in the range of 300 to 600 grams. ... The Fort Worth Zoo is home to 5,000 animals of ____ different kinds. ... Dipsochelys - a genus of giant tortoise restricted to Madagascar (extinct) and Seychelles islands, containing six species: Dipsochelys abrupta - Madagascar, extinct Dipsochelys grandidieri - Madagascar, extinct Dipsochelys dussumieri - Aldabra Giant Tortoise, Aldabra atoll, Seychelles Dipsochelys hololissa - Seychelles giant tortoise, granitic islands of Seychelles Dipsochelys arnoldi - Arnolds Giant Tortoise, granitic islands of... Aldabrachelys is a genus proposed by Loveridge & Williams, 1954 for the Aldabra Giant Tortoise Dipsochelys dussumieri (or Geochelone gigantea). ...

Physical characteristics

The shell is a dark gray or black color with a high domed shape. It has stocky, heavily scaled legs to support its heavy body. The neck of the Aldabra Giant Tortoise is very long, even for its great size, which helps the animal to exploit tree branches up to a meter from the ground as a food source. Various seashells The hard, rigid outer covering of certain animals is called a shell. ... Gray (Gy) is the derived SI unit for absorbed dose, specific energy and kerma (kinetic energy in matter). ... Black is not a colour. ... In most biological nomenclature, a scale (Greek lepid, Latin squama) is a small rigid plate that grows out of an animals skin to provide protection. ... The coniferous Coast Redwood, the tallest tree species on earth. ... The metre, or meter (symbol: m) is the SI base unit of length. ...

Females are generally smaller than males, with average specimens measuring 90 cm (35 inches) in length and weighing 150 kg (330 pounds).

Diet

Primarily herbivores, Aldabra Tortoises will eat grasses, leaves, and woody plant stems. They occasionally indulge in small invertebrates and carrion, even eating the bodies of other dead tortoises. In captivity, Aldabra Giant Tortoises are known to enjoy fruits such as apples and bananas as well as compressed vegetable pellets. A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ... An area of grass-like plants Grass generally describes a monocotyledonous green plant in the family Poaceae, botanically regarded as true grasses. ... The leaves of a Beech tree A leaf with laminar structure and pinnate venation In botany, a leaf is an above-ground plant organ specialized for photosynthesis. ... Titan arum For other uses, see Carrion (disambiguation). ... Fruit stall in Barcelona, Spain. ... Binomial name Malus domestica Borkh. ... Species Hybrid origin; see text Banana is the common name used for herbaceous plants in the genus Musa, which because of their size and structure, are often mistaken for trees. ...

There is little fresh water available for drinking in the tortoises' natural habitat, therefore they obtain most of their moisture from their food. Water is a tasteless, odourless substance that is essential to all known forms of life and is known as the universal solvent. ...

Aldabra Giant Tortose Geochelone gigantea at Bristol Zoo, England

The Aldabra tortoise has two main varieties of shell. Specimens living in habitats with food available primarily on the ground have a more dome-shaped shell with front extending downward over the neck. Those living in an environment with food available higher up off the ground have a more flattened topped shell with the front raised to allow the neck to extend upward freely. Image File history File linksMetadata Download high resolution version (2160x1620, 829 KB) Aldabra Giant Tortose Geochelone gigantea at Bristol Zoo, England. ... Image File history File linksMetadata Download high resolution version (2160x1620, 829 KB) Aldabra Giant Tortose Geochelone gigantea at Bristol Zoo, England. ...

In captivity and as pets

The Aldabra tortoise is recently becoming more available in the pet trade. The price still makes them somewhat of an exclusive animal, costing between $1,000 and $20,500 depending on size as of 2006. Care for these tortoises requires a good deal of commitment. They are very powerful as adults, and can be destructive in a typical suburban setting; capable of ramming through fences and doors. Fairly expensive accommodations are necessary to contain these tortoises and keep them at a comfortable temperature throughout the year (80-95 F). Genera Chersina Dipsochelys Furculachelys Geochelone Gopherus Homopus Indotestudo Kinixys Malacochersus Manouria Psammobates Pyxis Testudo A tortoise is a land-dwelling reptile of the order Testudines. ...

Breeding

Aldabra Giant Tortoises reach sexual maturity when they attain about half their final size. It seems that reaching sexual maturity is determined by size, not by age.

Between February and May, females lay between 9 and 25 rubbery eggs in a shallow, dry nest. Usually less than half of the eggs are fertile. Females can produce multiple clutches of eggs in a year. After incubating for about 8 months, the tiny, independent young hatch between October and December. In most birds and reptiles, an apple (Latin ovum) is the zygote, resulting from fertilization of the ovum. ... A basket style nest A nest is place of refuge built to hold an animals eggs and/or provide a place to raise their offspring. ...

Range and habitat

The main population of the Aldabra Giant Tortoise resides on the islands of the Aldabra Atoll in the Seychelles. The atoll has been protected from human influence and is home to some 152,000 giant tortoises, the world's largest population of the animal. Another isolated population of the species resides on the island of Zanzibar. The tortoises exploit many different kinds of habitat including grasslands, low scrub, mangrove swamps, and coastal dunes. Map of Aldabra Atoll Aldabra and Assumption Island Aldabra Atoll Aldabra is a raised coral atoll in the Indian Ocean virtually untouched by humans, with distinctive island fauna, including the Aldabra Giant Tortoise. ... Map of populations by country Taiwanese people waiting for the Taipei Rapid Transit System in Taipei, Republic of China(Taiwan). ... Motto: Uhuru na Umoja (Swahili: Freedom and Unity) Anthem: Mungu ibariki Afrika (God Bless Africa) Capital (and largest city) Stone Town English Government Republic  - President Amani Abeid Karume  - Prime Minister Shamsi Vuai Nahodha Independence From the United Kingdom   - Tanganyika December 9, 1961   - Zanzibar December 19, 1963   - Merge April 26, 1964... An Inner Mongolian Grassland. ... Scrubland is plant community characterized by scrub vegetation. ... Above and below water view at the edge of the mangal. ...

A peculiar kind of habitat has evolved due to the grazing pressures of the tortoises: "tortoise turf," a comingling of 21 species of grasses and herbs. Many of these distinct plants are natually dwarfed and grow their seeds not from the tops of the plants, but closer to the ground to avoid the tortoises' close cropping jaws. In 1832, while traveling on the Beagle, naturalist Charles Darwin collected giant fossils in South America. ... A ripe red jalapeno cut open to show the seeds For other uses, see Seed (disambiguation). ... It has been suggested that this article or section be merged with mandible. ...

As the largest animal in its environment, the Aldabra tortoise performs a role similar to that of the elephant. Their vigorous search for food fells trees and creates pathways used by other animals. For other uses, see Elephant (disambiguation). ...

Aldabra tortoise at Zoo Atlanta

Image File history File linksMetadata Download high-resolution version (1220x1022, 193 KB) Summary Photo by Brad Cassagne Licensing I, the creator of this work, hereby grant the permission to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1. ... Image File history File linksMetadata Download high-resolution version (1220x1022, 193 KB) Summary Photo by Brad Cassagne Licensing I, the creator of this work, hereby grant the permission to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1. ... Zoo Atlanta is an AZA-accredited wildlife park and major attraction in Atlanta, Georgia. ...

Behavior

Aldabra tortoises are found both individually and in herds, which tend to gather mostly on open grasslands. They are most active in the mornings when they spend time browsing for food. They dig underground burrows or rest in swamps to keep cool during the heat of the day.

While they are characteristically slow and cautious, they are capable of appreciable speed, especially when tempted with a treat. They are also known to attempt perilous acrobatic feats, rising precariously on their hind legs to reach low branches. They risk death by tipping onto their backs and being unable to right themselves.

They are also excellent swimmers, being naturally buoyant. This factor has allowed the spread and eventual speciation of many kinds of related tortoises across the Indian Ocean. Charles Darwins first sketch of an evolutionary tree from his First Notebook on Transmutation of Species (1837) Speciation is the theory of the evolutionary process by which new biological species are believed by some to arise. ...

The tortoises are not domestic or tame, but they are remarkably indifferent to the presence of humans. They do not seem to have any fear of people; some even seek them out for attention. Some like to have their heads patted, others enjoy having their necks scratched where they meet their plastron. The plastron is the nearly flat part of the shell structure of a tortoise, what we would call the belly, similar in composition to the carapace; with an external layer of horny material divided into plates called scutes and an underlying layer of interlocking bones. ...

Life span

Large tortoises are among the longest-lived animals on the planet. Some individual Aldabra Giant Tortoises are thought to be over 100 years of age, but this is difficult to verify because they tend to outlive their human observers. Adwaitya (The One and Only) was reputedly one of four brought by British seamen from the Seychelles Islands as gifts to Robert Clive of the British East India Company in the 18th century and came to Kolkata Zoo in 1875. At its death in March 2006 at the Kolkata (formerly Calcutta) Zoo in India, Adwaitya is reputed to have reached the longest ever measured life-span of 255 years (birth year 1750), although the accuracy of this is disputed due to a lack of contemporary records. Adwaitya (The Only One) (1750 - March 2006) was an Aldabra Giant Tortoise that is believed to have lived from 1750 to 2006, thus being the longest living animal known to man. ... Robert Clive, 1st Baron Clive Robert Clive, 1st Baron Clive of Plassey (September 29, 1725 - November 22, 1774) was the statesman and general who established the empire of British India. ... The BEIC, sometimes referred to as John Company, was a joint-stock company which was granted an English Royal Charter by Elizabeth I on December 31, 1600, with the intention of favouring trade privileges in India. ... Adwaitya (The Only One) (1750 - March 2006) was an Aldabra Giant Tortoise that is believed to have lived from 1750 to 2006, thus being the longest living animal known to man. ... Maximum life span is a measure of the maximum number of years a member of a group has been observed to survive. ...

Conservation

The Aldabra Giant Tortoise has an unusually long history of organized conservation. Charles Darwin worked with the government of Mauritius to establish a preserve at the end of the 19th century. The related, but distinct, species of giant tortoise from the Seychelles islands (Seychelles giant tortoise Dipsochelys hololissa and Arnold's Giant Tortoise D. arnoldi) are the subject of a captive breeding and reintroduction programme by the Nature Protection Trust of Seychelles. Charles Robert Darwin FRS (12 February 1809 – 19 April 1882) was an English naturalist [1] who achieved lasting fame by producing considerable evidence that species originated through evolutionary change, at the same time proposing the scientific theory that natural selection is the mechanism by which such change occurs. ... Seychelles giant tortoise Dipsochelys hololissa has been thought to be extinct since the mid-19th century due to over-explotation on the granitic Seychelles islands. ... Binomial name Dipsochelys arnoldi Arnolds Giant Tortoise (Dipsochelys arnoldi) also known as the Seychelles saddle-backed tortoise inhabited the granitic Seychelles islands until around 1840. ...

Sources and resources

• Bourn, D. Reproductive Study of Giant Tortoises on Aldabra. J. Zool., London, Vol. 182, 1977, pp. 27-38.
• Chambers, Paul. A Sheltered Life: The Unexpected History of the Giant Tortoise. John Murray (Publishers), London. 2004. ISBN 0-7195-6528-6.
• Collins, Dave. "Captive Breeding and Management of the Aldabra Tortoise." Presented to 8th International Herpetological Symposium, Jacksonville Zoo, Jacksonville, Fl., 1984.
• Gerlach, Justin. 'Giant Tortoises of the Indian Ocean' Chimiara publishers, Frankfurt. 2004
• Gibson, C.W.D. and J. Hamilton. Population Processes in a Large Herbivorous Reptile: The Giant Tortoises of Aldabra Atoll. Occologia (Berlin), Spring-Summer, 1984, pp. 230-240.
• Grubb, P. The Growth, Ecology, and Population Structure of the Giant Tortoises on Aldabra. Phil. Trans. Roy. Soc. Lond. B, Vol. 260, 1971, pp. 327-372.
• Pritchard, Peter C.H. Encyclopedia of Turtles. Neptune, New Jersey: T.F.H. Publications, Inc. Ltd., 1979.
• Spratt, David M.J. Operation Curiesue: A Conservation Programme for the Aldabra Giant Tortoise in the Republic of Seychelles. Int. Zoo Yb., Vol. 28, 1989, pp. 66-69.
• Stearns, Brett C. Captive Husbandry and Propagation of the Aldabra Giant Tortoise. Int. Zoo Yb., Vol. 27, 1988, pp. 98-103.
• Stoddart, D. R. Retrospect and Prospect of Aldabra Research. Nature, March 15, 1969, pp. 1004-1006.
• Stoddart, D. R. The Aldabra Affair. Biological Conservation, 1974, pp. 63-69.
• Swingland, Ian R. Securing the Tortoises Future. Country Life, August 30, 1984, pp. 568-569.
• Swingland, Ian R. Aldabran Giant Tortoise. The Conservation Biology of Tortoises, Occasional Papers of the IUCN Species Survival Commission (SSC), No. 5, 1989.

March 15 is the 74th day of the year in the Gregorian Calendar (75th in Leap years). ... 1969 (MCMLXIX) was a common year starting on Wednesday (the link is to a full 1969 calendar). ... August 30 is the 242nd day of the year in the Gregorian Calendar (243rd in leap years), with 123 days remaining. ... 1984 (MCMLXXXIV) was a leap year starting on Sunday of the Gregorian calendar. ...

References

• Tortoise & Freshwater Turtle Specialist Group (1996). Geochelone gigantea. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Listed as Vulnerable (VU D2 v2.3)

The IUCN Red List of Threatened Species (also known as the IUCN Red List and Red Data List), created in 1963, is the worlds most comprehensive inventory of the global conservation status of plant and animal species. ... The World Conservation Union or International Union for Conservation of Nature and Natural Resources (IUCN) is an international organization dedicated to natural resource conservation. ... May 11 is the 131st day of the year in the Gregorian Calendar (132nd in leap years). ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ...

External links

• ARKive multimedia
• Sea World Animal Bytes
• Aldabra Giant Tortoise at EMY System and World Turtle Database
• Seychelles Giant Tortoise Conservation Project
• Aldabra Giant Tortoise