The tuatara is a unique reptile native to New Zealand and belongs to the order Rhynchocephalia. Despite its lizard-like appearance, tuatara are not lizards; they are the only surviving members of a distinct lineage that dates back to the time of the dinosaurs. In fact, they represent one of the most ancient groups of reptiles still in existence today.
Key features of the tuatara include:
1. **Appearance**: Tuatara resemble lizards but have several distinctive characteristics. They have a spiky crest along their back, rough, greenish-brown skin, and a beak-like mouth. Their most unusual feature is a “third eye” located on the top of their heads, which is covered by a translucent scale and is thought to be light-sensitive, although its exact function is still debated.
2. **Habitat**: Tuatara are found only in New Zealand, primarily on offshore islands where they are protected from introduced predators such as rats and stoats. They inhabit a range of habitats, including forests, grasslands, and coastal areas.
3. **Behavior**: Tuatara are primarily nocturnal and spend much of their time hiding in burrows or crevices during the day. They are solitary animals and are known for their slow metabolism and longevity; tuatara can live for over 100 years in the wild.
4. **Reproduction**: Tuatara have a unique reproductive biology. Males become sexually mature around 15 years of age, while females reach maturity later, at around 20 years. They have a slow reproductive rate, with females laying relatively small clutches of eggs every four years or so. Interestingly, tuatara eggs require a specific temperature to hatch, with cooler temperatures producing males and warmer temperatures producing females.
Tuatara are considered a living fossil because they have remained relatively unchanged for millions of years. They provide valuable insights into the evolutionary history of reptiles and offer a glimpse into ancient ecosystems that existed long before the arrival of humans.