Wildlife
Turtles, terrapins and tortoises are all in one order, called the Testudines. They all have a shell, though only certain species can withdraw their lead and limbs into it. All the many types of turtle, terrapin and tortoise lay eggs. In some, the temperature at which the egg incubates will decide whether the embryo becomes male or female.
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Frozen turtles
Painted turtles have a natural anti-freeze that helps them survive winter.
Painted turtles have a natural anti-freeze that helps them survive winter.
Abandoned pets
The 1990s craze for pet terrapins is having serious repercussions on our parkland wildlife.
The 1990s craze for pet terrapins is having serious repercussions on our parkland wildlife.
Saving turtles
Saira Khan reports from Sri Lanka on the plight of the world's turtles.
Turtles range right across the world's oceans, making them difficult animals to survey, but by all accounts their numbers are falling fast. All seven species of sea turtle are now listed as either endangered or critically endangered and the prognosis doesn’t seem to be improving. Over 70% of leatherback turtles, the largest of all the sea turtles, have been lost globally since the 1980s. All species suffer from a multitude of problems including harmful fishing methods, net entanglement or swallowing marine debris, increased beach and coastal developments hampering both laying of eggs and the hatchlings reaching the sea and, most importantly, illegal hunting for their shells, eggs and meat.
The shading illustrates the diversity of this group - the darker the colour the greater the number of species. Data provided by WWF's Wildfinder.
Sea turtles
Eastern box turtle (species)
Giant river turtle (species)
TortoisesDiscover the other animals and plants that lived during the following geological time periods.
Turtles are reptiles of the order Testudines (the crown group of the superorder Chelonia), characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may either refer to the Testudines as a whole, or to particular Testudines which make up a form taxon that is not monophyletic.
The order Testudines includes both extant (living) and extinct species. The earliest known turtles date from 215 million years ago, making turtles one of the oldest reptile groups and a more ancient group than lizards, snakes and crocodiles. Of the many species alive today, some are highly endangered.
Like other reptiles, turtles are ectotherms—their internal temperature varies according to the ambient environment, commonly called cold-blooded. However, leatherback sea turtles have noticeably higher body temperature than surrounding water because of their high metabolic rate.
Like other amniotes (reptiles, dinosaurs, birds, and mammals), they breathe air and do not lay eggs underwater, although many species live in or around water. The largest turtles are aquatic.
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Take a trip through the natural world with our themed collections of video clips from the natural history archive.
Going, going, gone
One third of known species are under threat - do they have more than a future on film? We've unearthed footage of some remarkable animals, plants and habitats that are facing an imminent threat to their survival.
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Jurassic period
Cretaceous period
Palaeocene epoch
Eocene epoch
Oligocene epoch
Miocene epoch
Pliocene epoch
Pleistocene epoch
Holocene epoch