Orokonui Ecosanctuary/Reptiles

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Tuatara

In Māori tradition tuatara were seen as kaitiaki guardians of knowledge,
by early Europeans tuatara were thought of as an example of failed evolution, 
today tuatara are seen as survivors, symbols of a sustainable future with humans.
  • Tuatara are reptiles endemic to New Zealand
  • Tuatara = peaks on back
  • Resemble lizards but part of a distinct lineage, the order Rhynchocephalia
    • Two species of tuatara are the only surviving members of their order who lived about the same time as dinosaurs
      • Common ancestor are the squamates (lizards and snakes)
        • Relatives of tuatara died out about 60 million years ago
  • Nocturnal
  • Food - beetles, crickets,spiders, occasionally frogs, lizards, bird's eggs and chicks
    • May also eat own young - hence diurnal nature of juveniles
  • Teeth - attached to jaw bones - 2 rows on top one on bottom
    • Slide back and forth between rows
  • Tuatara's teeth are not replaced - sharp projections of the jaw bone
    • As teeth wear down, older tuatara switch to softer prey such as earthworms, larvae, and slugs
      • Eventually chewing food between smooth jaw bones
  • Nostrils inhale air into mouth
    • Windpipe into simple single chambered lungs
      • Breath in 2 - 26 times per minute (increases due to temperature/activity)
        • Can hold breathe for hours, can remain under water for long periods
  • Loses tail in self defence
    • Breaks on vertebra via stress fractures
      • Regrows - smaller and sometimes forked!
  • Body temperature (when active) ranges from 5 - 30°C
    • Optimal body temperature 20-22 °C
      • Body temperature rises up to 6°C warmer than air temperature
        • Basking can raise body temperature rapidly, loosing body heat less quickly
          • Maybe able to tolerate freezing
  • Tuatara are host to a number of parasites
    • Including blood-sucking ticks
      • Chigger mites that feed on tissue and lymph (Neotrombicula sphenodonti)
        • Blood parasites that live within the blood cells (Haemogregarina tuatarae)
          • Intestinal worms (Hatterianema hollandei)
  • Lay eggs in burrows
    • 8-24 months of incubation - without adult assistance
      • Often shares burrow with sea birds also eats eggs and chicks!
  • Eyes can focus independently and can see well day and night
  • Photoreceptive eye (parietal eye) - the "third eye"
    • Has its own lens, cornea, retina with rod-like structures, and degenerated nerve connection to the brain
      • Only visible in hatchlings, through a translucent patch at the top centre of the skull
        • Useful in absorbing ultraviolet rays to produce vitamin D, determine light/dark cycles, and help with thermoregulation
  • Can hear but have no external ears
  • The tuatara Sphenodon punctatus has been protected by law since 1895

Tuatara in Maori tradition

  • Found in middens
  • Appear in cave drawings
  • Bones used as awls
  • Pendants representing tuatara
  • Much carving features tuatara
  • To remove tapu from a place a tuatara was killed and then burnt by a tohuka
  • A belief that tuatara could enter the human body through orifices
    • Snoring risked inviting lizards

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Jewelled Gecko

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