Tuatara - Sphenodon Punctatus
From Wikipedia: The tuatara is endemic to New Zealand. The two species (Punctatus and the much rarer Guntheri) are the only surviving members of the Sphenodontians who flourished around 200 million years ago. Tuataras have been classified as an endangered species since 1895.
Tuataras were originally classified as lizards in 1831 when the British Museum received a skull but are equally related to lizards and snakes, which are their closest living relatives. Tuataras have been referred to as living fossils, meaning they have remained mostly unchanged throughout their entire history. Adults are about 50 cm long and weigh 0.5 (females) to 1 kg (males).
The spiny crest on their back, made of triangular soft folds of skin, is bigger in males and can be stiffened for display. Both eyes can focus independently, and are specialised with a "duplex retina" containing two types of visual cells for vision by both day and night, and a tapetum lucidum which reflects on to the retina to enhance vision at night. There is also a nictitating membrane.
The tuatara has a third eye on the top of its head called the parietal eye. It has its own lens, cornea, retina with rod-like structures and degenerated nerve connection to the brain, suggesting it evolved from a real eye. The parietal eye is only visible in hatchlings, which have a translucent patch at the top centre of the skull. After 4-6 months it becomes covered with opaque scales and pigment; its purpose is unknown, but it may be useful in absorbing ultraviolet rays to manufacture vitamin D, as well as to determine light/dark cycles, and help with thermoregulation. Of all extant tetrapods, the parietal eye is most pronounced in the tuatara. In mammals, it has become the pineal gland.
There are several Tuatara breeding programmes within New Zealand. Southland Museum and Art Gallery in Invercargill, at which I saw this example, was the first to have a tuatara breeding programme; they breed Sphenodon punctatus. The name "tuatara" derives from the Maori language, meaning "peaks on the back". Tuataras feature in a number of indigenous legends, and are held as ariki (God forms). Tuataras are regarded as the messengers of Whiro, the god of death and disaster, and Maori women are forbidden to eat them.
Tuatara - Sphenodon Punctatus
From Wikipedia: The tuatara is endemic to New Zealand. The two species (Punctatus and the much rarer Guntheri) are the only surviving members of the Sphenodontians who flourished around 200 million years ago. Tuataras have been classified as an endangered species since 1895.
Tuataras were originally classified as lizards in 1831 when the British Museum received a skull but are equally related to lizards and snakes, which are their closest living relatives. Tuataras have been referred to as living fossils, meaning they have remained mostly unchanged throughout their entire history. Adults are about 50 cm long and weigh 0.5 (females) to 1 kg (males).
The spiny crest on their back, made of triangular soft folds of skin, is bigger in males and can be stiffened for display. Both eyes can focus independently, and are specialised with a "duplex retina" containing two types of visual cells for vision by both day and night, and a tapetum lucidum which reflects on to the retina to enhance vision at night. There is also a nictitating membrane.
The tuatara has a third eye on the top of its head called the parietal eye. It has its own lens, cornea, retina with rod-like structures and degenerated nerve connection to the brain, suggesting it evolved from a real eye. The parietal eye is only visible in hatchlings, which have a translucent patch at the top centre of the skull. After 4-6 months it becomes covered with opaque scales and pigment; its purpose is unknown, but it may be useful in absorbing ultraviolet rays to manufacture vitamin D, as well as to determine light/dark cycles, and help with thermoregulation. Of all extant tetrapods, the parietal eye is most pronounced in the tuatara. In mammals, it has become the pineal gland.
There are several Tuatara breeding programmes within New Zealand. Southland Museum and Art Gallery in Invercargill, at which I saw this example, was the first to have a tuatara breeding programme; they breed Sphenodon punctatus. The name "tuatara" derives from the Maori language, meaning "peaks on the back". Tuataras feature in a number of indigenous legends, and are held as ariki (God forms). Tuataras are regarded as the messengers of Whiro, the god of death and disaster, and Maori women are forbidden to eat them.