understanding - tuatata
Though New Zealand's tuatara looks very much like a lizard, it's not. The tuatara is the last of its kind, the sole living member of the reptilian order of Rhynchocephalia. New research, published this week in the journal Nature, suggests the tuatara shares genetic heritage with both reptiles and mammals. A once-species-rich order of reptiles called the Rhynchocephalia lived across the globe during the time of the dinosaurs. Just one of these species survives today: the tuatara. Found only in New Zealand, tuatara are a taonga (‘special treasure’) for Maori people. The reptiles have a set of intriguing traits (including longevity and an unusual combination of bird- and reptile-like morphological features) that have led to uncertainty over their place in the evolutionary tree. Rhynchocephalia ("beak-heads") is an order of lizard-like reptiles that includes only one living species, the tuatara (Sphenodon punctatus) of New Zealand, which is thought to have two subspecies (Sphenodon punctatus punctatus and Sphenodon punctatus guntheri) the latter was recognised as a separate species from 1989 to 2009.
tuatara
Department of Conservation rangers Lee and Joyce are in search of a rare animal found only on an island in New Zealand. Follow them on their quest to find and breed two Tuataras, an ancient reptile that predates the dinosaurs. RHYNCHOCEPHALIA :
Despite its current lack of diversity, the Rhynchocephalia at one time included a wide array of genera within multiple (now extinct) families, and represents a lineage stretching at least as far back as the Middle Triassic. Most rhynchocephalians belong to the group Sphenodontia ("wedge-teeth"), which are characterized by a hooked beak-like structure at the tip of the snout formed by enlarged premaxillary teeth. BIOLOGICAL CURIOSITY : The tuatara genome is considerably bigger than the human genome, and it has a unique constitution. It contains a lot of repetitive DNA segments that are unique to the species and have no known function," explains Fergal Martin, Vertebrate Annotation Coordinator at EMBL-EBI. The sequence of the tuatara genome revealed a number of aspects of this reptile's lifestyle. Although tuatara are predominantly nocturnal animals, their DNA carries a high number of genes involved in colour vision, which might help day-active juveniles escape from their predators |
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rHYNCHOCEPHALIA :
