Our Changing World

Thursday 1 April 2010, with Alison Ballance & Ruth Beran

Audio from Thursday 1 April 2010

Not all audio is available due to copyright restrictions.

  • Rangatira Night Shift ( 13′ 02″ )

    21:06 At night Rangatira Island is alive with seabirds, wetas, spiders, and war whooping scientists catching Chatham petrels

  • Artificial Mouth ( 12′ 40″ )

    21:20 University of Otago's Chris Sissons and Lisa Wong are using an artificial mouth to study dental plaque

  • Poisonous Plants ( 12′ 20″ )

    21:34 The book Plants that Poison is a guide to New Zealand's poisonous plants, from green potatoes to castor beans

  • Hookworms ( 12′ 43″ )

    21:46 Graham Le Gros and Mali Camberis are studying hookworms in the hope of developing a vaccine as well as treatments for diseases

On This Programme

Rangatira Island at Night

'Petrel boards' to spread the wearer's weight, Graeme Taylor with a spotlight, and a sooty shearwater

'Petrel boards' act like snow shoes to spread the wearer's weight, Graeme Taylot spotlighting Chatham petrels, and a sooty shearwater (images: A. Ballance)

In the third episode of the Chatham Island series, Alison Ballance heads out at night with the Department of Conservation's Abi Liddy and Graeme Taylor in search of seabirds. The pair are using war whoops and spotlights to catch and band young Chatham petrels returning to the island to find a mate. As the night progresses Alison walks the nightly 'prion count', sees lots of wetas, and tries her war whooping skills, before finishing at dawn with a chorus of sooty shearwaters.

Nocturnal invertebrates on South East Island

Chatham island speargrass weevils, unidentified native slug, and a Rangatira spider (images: A. Ballance)

Artificial mouth

The artificial mouth; Lisa Wong and Chris Sissons; and a 21 day old plaque

(The artificial mouth, Lisa Wong and Chris Sissons, and a 21 day old plaque)

At the University of Otago, Wellington, there's an artificial mouth with saliva. It's given meals, occasionally it even has teeth, and was developed by the Dental Research Group to study up to 12 different plaques under different test conditions. For example, the system can be fed with different frequencies of sucrose or different mouthwashes, to determine the impact on the bacteria in the plaque. The result of allowing plaque to build up on teeth can be tooth decay or gum disease, but it is also associated with many other health problems. Ruth Beran went to see the artificial mouth herself and talks with Lisa Wong and Chris Sissons, who heads the Dental Research Group.

Poisonous Plants

Book coverPlants that Poison: A New Zealand Guide is written by botanist Henry Connor and toxicologist John Fountain. It is arranged into categories such as berries and fruits, seeds and pods, and trees and shrubs so that people can quickly identify potential poisonous plants.

Published by Manaaki Whenua Press the guide is available in bookshops.

The National Poisons Centre is based in Dunedin, and can be reached on 0800 POISON.

Hookworms

Graham Le Gros and Mali Camberis

It is estimated that about a billion people around the world are infected with human hookworm, and Graham Le Gros (right) and Mali Camberis (left) from the Malaghan Institute of Medical Research are researching these nematodes in the hope of developing a vaccine.

By studying the hookworms' life cycle and the molecules they produce, the scientists also hope to find treatments for various diseases. The concept being part of the hygiene hypothesis, that while hookworms can cause various negative side effects like iron deficiency anaemia, they have also developed strategies for modulating the human immune system, strategies which may have some benefit for the prevention of inflammatory diseases like Crohn's disease. Another possibility is that by looking at how the human body responds to the allergens that hookworms produce, they may provide insights for diseases like asthma.

Next Week

Revegetation on Mangere Island in the Chathams, Roy Kerr and black holes and more.