We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Tuatara?

Michael Anissimov
By
Updated Mar 05, 2024
Our promise to you
AllThingsNature is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At AllThingsNature, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

The tuatara is a unique reptile endemic to the northern tip of New Zealand. Though it superficially resembles a lizard, the tuatara is a sphenodontian, a sister clade of squamates, the reptile group that includes both lizards and snakes. Sphenodontians were highly successful about 200 million years ago, including many terrestrial forms and even an aquatic form. At the time, sphenodontians occupied many of the niches that are today taken by lizards. The tuatara is the only surviving sphenodontian.

Although it is sometimes called a "living fossil," the tuatara has actually changed extensively in the last 200 million years, including developing adaptations for the colder weather of the Cenozoic era. A broad survey of molecular evolution rates across diverse animal genera revealed that the tuatara is one of the fastest-evolving species among the groups studied. Like many reptiles, the tuatara retains the basic lizard-like body plan, which dates back to the earliest reptiles living 315 million years ago, such as Hylonomus.

The tuatara is of great interest to those studying the evolution of reptiles and tetrapods in general. Of all the amniotes, the tuatara is among the least specialized. Its locomotion is considered amphibian-like, and its heart is the most primitive of all amniotes. Instead of distinct teeth that can fall out and grow back, the tuatara's teeth are direct projections from its jawbone. When they wear down, they cannot be replaced, so old tuataras must switch to softer food such as earthworms. The tuatara lacks an earhole or eardrums, the middle ear instead being filled with sensory tissue. As a result, the animal displays poor hearing.

Of all animals, the tuatara displays the best example of a parietal eye, a relict third eye on the top of its head, consisting of its own retina, cornea, lens, and a degenerated bundle of nerves to carry its information to the brain. In hatchlings, the parietal eye is clearly visible, but between four to six months, it becomes covered in opaque scales and pigment. The function of the eye is unknown, but in salamanders the parietal eye has been shown to determine the polarization of light, allowing it to find the sun even under extensive cloud cover.

Frequently Asked Questions

What exactly is a tuatara?

The tuatara is a reptile endemic to New Zealand, belonging to the order Rhynchocephalia. This order was widespread around 200 million years ago, but now the tuatara is its only surviving member, making it a living fossil. They resemble lizards but are part of a distinct lineage and have unique biological features such as a third "parietal" eye and well-developed hearing despite lacking external ear openings.

How long do tuataras live?

Tuataras are known for their exceptional longevity, with some individuals living over 100 years. According to research, their slow growth rate and low metabolism contribute to their long lifespan. They continue to grow until they are about 35 years old and maintain good health well into their senior years, which is unusual among vertebrates.

What does the tuatara's diet consist of?

Tuataras are primarily insectivores but have an opportunistic diet that includes beetles, spiders, crickets, and other invertebrates. They also eat small vertebrates, such as birds, lizards, and frogs. Their hunting strategy is to sit and wait, relying on their excellent night vision to ambush prey in the dark.

Is the tuatara endangered?

Yes, the tuatara is considered vulnerable to extinction. Habitat destruction, introduced predators, and climate change pose significant threats to their survival. Conservation efforts in New Zealand involve predator-free sanctuaries and breeding programs to help protect and increase the tuatara population, which is crucial for maintaining this species that has been around since the age of the dinosaurs.

How does the tuatara reproduce?

Tuataras have a unique reproductive system with a long gestation period. Females lay eggs once every four years, and it can take 12-15 months for the eggs to hatch. Temperature plays a crucial role in determining the sex of the offspring, with warmer temperatures favoring male hatchlings. This temperature-dependent sex determination is a subject of concern in the face of global warming.

What is the significance of the tuatara's third eye?

The tuatara's third eye, also known as the parietal eye, is a photoreceptive organ located on the top of its head. It is more prominent in juveniles and becomes covered with scales in adults. While its exact function is not fully understood, it is believed to play a role in regulating circadian rhythms and hormone production related to seasonal changes.

AllThingsNature is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Michael Anissimov
By Michael Anissimov

Michael is a longtime AllThingsNature contributor who specializes in topics relating to paleontology, physics, biology, astronomy, chemistry, and futurism. In addition to being an avid blogger, Michael is particularly passionate about stem cell research, regenerative medicine, and life extension therapies. He has also worked for the Methuselah Foundation, the Singularity Institute for Artificial Intelligence, and the Lifeboat Foundation.

Discussion Comments

By anon258447 — On Apr 02, 2012

Great but I was expecting more about adaptations.

Michael Anissimov

Michael Anissimov

Michael is a longtime AllThingsNature contributor who specializes in topics relating to paleontology, physics,...

Read more
AllThingsNature, in your inbox

Our latest articles, guides, and more, delivered daily.

AllThingsNature, in your inbox

Our latest articles, guides, and more, delivered daily.