The Tuatara: New Zealand's Reptile That Outlived the Dinosaurs

It looks exactly like a lizard, but it is not one. It has a literal third eye on top of its head, teeth fused permanently to its jawbone, no external ears, and a lifestyle so slow that a 111-year-old male recently became a first-time father. The tuatara is New Zealand's greatest reptilian survivor, and its existence forces us to rethink how survival works over millions of years.This episode dives into the biology and conservation of the tuatara, the sole surviving species of an entire order of reptiles that thrived alongside the dinosaurs. We unpack its bizarre anatomy, its cold-adapted slow-motion metabolism, the genomic secrets behind its century-long lifespan, and the new climate threat that could doom it even behind predator-proof fences.It is the only survivor of the order Rhynchocephalia, a lineage that split off around 240 million years agoIts teeth are fused to the jawbone with no roots, so a century of chewing wears them smooth, forcing old animals to switch to soft foodsThe third eye is a light meter feeding the pineal gland, regulating the circadian rhythm of a reptile that overheats fatally above about 82 degrees FahrenheitSelenoprotein genes in its 5-to-6-billion-base-pair genome neutralize free radicals, helping explain how Henry fathered offspring at age 111Temperature-dependent sex determination means a two-degree rise in soil can flip nests to nearly all male, so conservationists now shade and incubate eggs