Tortoise Totally Explained

Everything about Testudinidae totally explained

Tortoises or land turtles are land-dwelling reptiles of the family of Testudinidae, order Testudines. Like their marine cousins, the sea turtles, 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 tortoise has both an endoskeleton and an exoskeleton. Tortoises can vary in size from a few centimeters to two meters. Tortoises tend to be diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals. The biggest operational difference between tortoises and turtles is that tortoises are unable to swim; indeed, they can't float, whereas turtles can.

Etymology

Biology

Birth

Female tortoises dig nesting burrows in which they lay from one to thirty eggs. Egg laying typically occurs at night, after which the mother tortoise covers her clutch with sand, soil, and organic material. The eggs are left unattended, and depending on the species, take from 60 to 120 days to incubate. The size of the egg depends on the size of the mother and can be estimated by examining the width of the cloacal opening between the carapice and plastron. The plastron of a female tortoise often has a noticeable V-shaped notch below the tail to facilitate passing the eggs. Upon completion of the incubation period, a fully-formed hatchling uses an egg-tooth to break out of its shell. It digs to the surface of the nest and begins a life of survival on its own. Hatchlings are born with an embryonic egg sac which serves as a source of nutrition for the first 3 to 7 days until they've the strength and mobility to find food. Juvenile tortoises often require a different balance of nutrients than adults, and therefore may eat foods which a more mature tortoise would not. For example, it's common that the young of a strictly herbivorous species will consume worms or insect larvae for additional protein.

Lifespan

There are many old wives tales about the age of turtles and tortoises, one of which being that the age of a tortoise can be deducted by counting the number of concentric rings on its carapace, much like the cross-section of a tree. This is, of course, not true, since the growth of a tortoise depends highly on the access of food and water. A tortoise that has access to plenty of forage (or is regularly fed by its owner) will grow faster than a desert tortoise that goes days without eating.
Tortoises generally have lifespans comparable with those of human beings, and some individuals are known to have lived longer than 150 years. Because of this, they symbolize longevity in some cultures, such as China. The oldest tortoise ever recorded, almost the oldest individual animal ever recorded, was Tui Malila, who was presented to the Tongan royal family by the British explorer Captain Cook shortly after its birth in 1777. Tui Malila remained in the care of the Tongan royal family until its death by natural causes on May 19, 1965. This means that upon its death, Tui Malila was 188 years old. The record for the longest-lived vertebrate is succeeded only by one other, a koi fish named Hanako whose death on July 17 1977 ended a 226 year life span.
The Alipore Zoo in India was the home to Adwaitya, which zoo officials claimed was the oldest living animal until its death on March 23, 2006. Adwaitya (sometimes spelled with two d's) was an Aldabra Giant Tortoise brought to India by Lord Wellesley who handed it over to the Alipur Zoological Gardens in 1875 when the zoo was set up. Zoo officials state they've documentation showing that Adwaitya was at least 130 years old, but claim that he was over 250 years old (although this has not been scientifically verified). Adwaitya was said to be the pet of Robert Clive. Harriet, a resident at the Australia Zoo in Queensland, was apocryphally thought to have been brought to England by Charles Darwin aboard the Beagle. Harriet died on June 23, 2006, just shy of her 176th birthday.

Sexual dimorphism

Many, though not all, species of tortoises are sexually dimorphic, though the differences between males and females vary from species to species. In some species, males have a longer, more protruding neck plate than their female counterparts, while in others the claws are longer on the females. In most tortoise species the female tends to be larger than the male. (Some believe that males grow quicker, while the female grows slower but larger.) The male also has a plastron that's curved inwards to aid reproduction. The easiest way to determine the sex of a tortoise is to look at the tail. The females, as a general rule have a smaller tail which is dropped down whereas the males have a much longer tail which is usually pulled up and to the side of the rear shell.

Diet

Most land based tortoises are herbivores, feeding on grazing grasses, weeds, leafy greens, flowers, and certain fruits. Their main diet consists of alfalfa, clover, dandelions, and leafy weeds, although that'll also eat various insects. Feeding tortoises cat or dog food is a common mistake, as both cat and dog food contain too much protein and lack other important nutrients for tortoises. Tortoises are not carnivores, and shouldn't be fed large amounts of protein, as it may cause shell deformation and other medical problems.
Many people make the mistake of assuming that all captive tortoises can be fed on the same diet. In reality, tortoise species vary greatly in their nutritional requirements. There is no "one fits all" diet. What works for one species won't always work for another. Commercial pellets are definitely to be avoided for all species, as they contain too much protein, this will lead to shell deformities.

Taxonomy

The following species list largely follows Ernst & Barbour (1989), as indicated by The Reptile Database. However, the newly erected genera Astrochelys, Chelonoidis and Stigmochelys have been retained within Geochelone.

Chersina
- Chersina angulata, Bowsprit Tortoise
Cylindraspis (All species Extinct)
- Cylindraspis indica, synonym Cylindraspis borbonica
- Cylindraspis inepta
- Cylindraspis peltastes
- Cylindraspis triserrata
- Cylindraspis vosmaeri
Dipsochelys
- Dipsochelys abrupta (Extinct)
- Dipsochelys arnoldi, Arnold's Giant Tortoise,
- Dipsochelys daudinii (Extinct)
- Dipsochelys dussumieri, Aldabra Giant Tortoise, common synonyms Geochelone gigantea, Aldabrachelys gigantea
- Dipsochelys grandidieri (Extinct)
- Dipsochelys hololissa, Seychelles giant tortoise
Geochelone
- Geochelone carbonaria, Red-Footed Tortoise; sometimes placed in distinct genus Chelonoidis
- Geochelone chilensis, Chaco or Chilean Tortoise; sometimes placed in distinct genus Chelonoidis
- Geochelone denticulata, Yellow-Footed Tortoise; sometimes placed in distinct genus Chelonoidis
- Geochelone elegans, Indian Star Tortoise
- Geochelone nigra, Galápagos Giant Tortoise; sometimes placed in distinct genus Chelonoidis
- Geochelone pardalis, Leopard Tortoise; sometimes placed in distinct genus Stigmochelys or in Psammobates
- Geochelone platynota, Burmese Star Tortoise
- Geochelone radiata, Radiated Tortoise; sometimes placed in distinct genus Astrochelys
- Geochelone sulcata, African Spurred Tortoise (Sulcata Tortoise)
- Geochelone yniphora, Angulated Tortoise, Madagascan (Plowshare) Tortoise; sometimes placed in distinct genus Astrochelys
Gopherus
- Gopherus agassizii, Desert Tortoise
- Gopherus berlandieri, Texas Tortoise
- Gopherus flavomarginatus, Bolson Tortoise
- Gopherus polyphemus, Gopher Tortoise
Homopus
- Homopus aerolatus, Parrot-Beaked Cape Tortoise
- Homopus boulengeri, Boulenger's Cape Tortoise
- Homopus femoralis, Karroo Cape Tortoise
- Homopus signatus, Speckled Cape Tortoise, Speckled Padloper
- Homopus bergeri, Berger's Cape Tortoise, Nama padloper, synonym Homopus solus
Indotestudo
- Indotestudo elongata, Elongated Tortoise
- Indotestudo forstenii, Travancore Tortoise, Forsten’s Tortoise
- Indotestudo travancorica, Travancore Tortoise
Kinixys
- Kinixys belliana, Bell's Hinge-Backed Tortoise
- Kinixys erosa, Serrated Hinge-Backed Tortoise
- Kinixys homeana, Home's Hinge-Backed Tortoise
- Kinixys lobatsiana, Lobatse Hingeback Tortoise
- Kinixys natalensis, Natal Hinge-Backed Tortoise
- Kinixys spekii, Speke's Hingeback Tortoise
Malacochersus
- Malacochersus tornieri, Pancake Tortoise
Manouria
- Manouria emys, Brown Tortoise (Mountain Tortoise)
- Manouria impressa, Impressed Tortoise
Psammobates
- Psammobates geometricus, Geometric Tortoise
- Psammobates oculifer, Serrated Star Tortoise
- Psammobates tentorius, African Tent Tortoise
Pyxis
- Pyxis arachnoides, Madagascan Spider Tortoise
- Pyxis planicauda, Madagascan Flat-Tailed Tortoise
Stylemys (all species extinct)
Testudo
Testudo atlas, Atlas tortoise, Colossochelys (Extinct)
Testudo graeca, Greek Tortoise (Spur-Thighed Tortoise)
Testudo hermanni, Herman's Tortoise
Testudo horsfieldii, Russian Tortoise (Horsfield's Tortoise, or Central Asian Tortoise)
Testudo kleinmanni, Egyptian Tortoise, incl. Negev Tortoise
Testudo marginata, Marginated Tortoise
Testudo nabeulensis, Tunisian Spur-thigh Tortoise

Tortoises in religion
In Hinduism, Kurma (Sanskrit: कुर्म) was the second avatar of Vishnu. Like the Matsya Avatara also belongs to the Satya yuga. Vishnu took the form of a half-man half-tortoise, the lower half being a tortoise. He is normally shown as having four arms. He sat on the bottom of the ocean after the Great Flood. A mountain was placed on his back by the other gods so that they could churn the sea and find the ancient treasures of the Vedic peoples.
Tortoises as pets
Many tortoises have specific temperature, roaming space, light, air moisture, and diet requirements. They are difficult to breed in captivity, so many are caught in the wild. Tortoises need outdoor space to roam. It isn't possible to house-train a tortoise.
Tortoises in popular culture
� :See main article Cultural depictions of turtles and tortoises

Further Information

Get more info on 'Testudinidae'.

External Link Exchanges

Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

<a href="http://tortoise.totallyexplained.com">Tortoise Totally Explained</a>

Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.