The tuatara is not a lizard. It is the sole survivor of an ancient reptile group, the Rhynchocephalia order, which thrived 200 million years ago. All other Rhynchocephalia species became extinct 60 million years ago.
The tuatara has unique physical traits separating it from lizards. Its teeth and skeleton structure differ, with a second row of upper teeth absent in lizards. Tuataras also have a third “parietal eye” on their head. This light-sensitive organ assisted their prehistoric ancestors.
Tuataras enjoy cooler weather, unlike warmth-loving lizards. They are also nocturnal, unlike most sun-basking lizards. Tuataras have no external ears.
At up to 30 years old, tuataras reach maturity and full size. Their potential lifespan is around 100 years. Slow reproduction contributes to low tuatara numbers.
The “living fossil” tuatara remains little changed from its dinosaur-age ancestors. It survives in isolated New Zealand habitats, a relic of reptile evolution. Continued conservation efforts can preserve the tuatara’s lineage.
Why do tuataras have a third eye?
Tuataras have three eyes. The third eye is on top of the head. It comes from a gland called the pineal body. The tuatara can see through the third eye. Tuataras live over 100 years.
Tuataras are found only in New Zealand. They look like lizards but are different. Tuataras enjoy cool weather. Lizards like warmth. Tuataras are nocturnal unlike lizards.
The third eye has a lens and retina. It links to the brain through a nerve. The eye is used to detect light. It helps set circadian rhythms.
The third eye scales over with age. It stays visible in young tuataras. Most vertebrates have symmetrical eyes. The tuatara’s third eye is asymmetrical. It may help the tuatara produce vitamin D and melatonin. It could also assist with sensing polarized light. This helps the tuatara orient itself on cloudy days.
Can I have a tuatara as a pet?
Tuataras resemble lizards but are separate. They enjoy cooler weather. Their most curious body part is a “third eye”. Tuataras are not for new reptile owners. They require an arboreal enclosure. Feeding them can prove difficult. New Zealand’s tuatara has the most pronounced “third eye”. Tuataras can fetch over $40,000 illegally. Their range puts them at risk. Tuataras grow slowly, taking 10-20 years to mature. Their average lifespan is 60-100 years. Some live 120 years. Tuataras shed skin yearly as adults. Young tuataras shed more often. The crest on a tuatara’s back signals males. It attracts females while breeding. Skulls differ between sexes. Tuataras eat invertebrates, lizards, frogs and bird chicks. Capturing tuataras to sell overseas is illegal. Their species existed for 190 million years. The “third eye” absorbs UV rays for vitamin D production. It aids with thermoregulation and light/dark cycles. Cooler temperatures suit tuataras. Females reproduce every four years. Eggs develop over years. Tuataras need conservation management. They hold international research interest.
Who eats tuatara?
The tuatara eats mostly insects at night like beetles, spiders, crickets, worms and cicadas. They will also eat other opportunistic foods like lizards, seabird eggs and chicks. The kiore, or Polynesian rat, is one of the main predators of the tuatara along with dogs, cats, stoats and ferrets.