Our Changing World

Thursday 17 April 2014, with Alison Ballance, Ruth Beran & Veronika Meduna

Audio from Thursday 17 April 2014

Not all audio is available due to copyright restrictions.

  • Unmanned Aerial Vehicles and Ecology ( 12′ 57″ )

    21:06 AUVs are being used to collect spatial data for ecological research after frustrations with satellite photos being obscured by cloud cover

  • Marcus Chown Explains the Big Stuff ( 13′ 54″ )

    21:20 Astrophysicist and writer Marcus Chown talks about his latest book, What a Wonderful World.

  • Estrogen Mimics ( 14′ 55″ )

    21:34 The plasticiser and pestidicide, dibutylphthalate, is being studied to determine why it may cause developmental defects in men

  • Bee-friendly Insecticides ( 11′ 10″ )

    21:46 University of Otago geneticist Peter Dearden is using the bee genome to develop a bee-friendly insecticide.

On This Programme

UAVs and Spatial Ecology

Barbara Breen and John Robertson with the SwampFox unmanned aerial vehicle

In their mission command room at AUT John Robertson holds the SawmpFox unmanned aerial vehicle or UAV, and Barbara Breen holds two cameras that are mounted under the UAV for taking aerial photos (image: A. Ballance)

A frustration with clouds obscuring details in satellite photos and a chance conversation has led to a fruitful collaboration at AUT, the Auckland University of Technology. With the help of colleague and model plane enthusiast John Robertson, and recently retired glider pilot and microbiologist John Brooks, spatial ecologist Barbara Breen has been developing the use of UAVs or Unmanned Aerial Vehicles as an ecological tool.

Alison Ballance joins Barbara and John Robertson in their mission command centre to find out more about the Kahu Hawk UAV – their first smaller glider – and their newer Swampfox. The Swampfox is New Zealand designed and built - the airframe was designed by Palmerston North-based Skycam UAV Ltd. in conjunction with the University of Queensland; the autopilot was designed by the New Zealand Defence Technology Agency, and the whole aircraft and systems were constructed Skycam UAV.

The UAV’s are a platform for taking aerial images, which are later stitched together using Pix4UAV software to create, for example, 3D images of forest patches, which can be real colour, near infrared or infrared.

The SwampFox was recently flown in Antarctica’s Dry Valleys in a collaboration with the University of Waikato to measure cyanobacteria mats from the air. Barbara and colleagues hope that it will also be used to detect grassgrub in pasture, wilding pines and, eventually, marine mammals.

Marcus Chown and the Big Stuff

astrophysicist and writer Marcus Chown

While in Wellington, Marcus Chown visited the sanctuary Zealandia to admire a tuatara. (image: V Meduna)

The British astrophysicist and writer Marcus Chown, the author of many popular science books and recipient of the 2011 Future Book Award for his iPad app The Solar System, is know for his ability to explain complex things, so when his publisher challenged him to write a book about everything, he produced What a Wonderful World: One man’s attempt to explain the big stuff. In this latest offering, he leaves his usual territory of cosmology to explore other scientific disciplines, and even a bit of economics.

For example, he explores why sex evolved, one of evolution’s trickiest questions that has baffled biologists since Charles Darwin, and he considers the advantages we might have had over our hominin cousins, including the Neanderthals.

Other topics include the origin of computers, money and capitalism, as well as several chapters on quantum theory, relativity and black holes, all topics his readers might be more familiar with.

You can read Veronika Meduna’s review From genes via markets to the big universe, and you can listen to his interview with Kim Hill, broadcast live from the NZ Festival in Wellington, during Writers Week.

Estrogen Mimics

Ian Shaw and Adam Ridden outside the lab

Ian Shaw and Adam Ridden outside the lab (image: University of Canterbury)

Chemicals in the environment with a similar structure to the female hormone estrogen can have feminising effects, such as reduced sperm count and early puberty in girls. University of Canterbury’s Ian Shaw has been studying estrogen mimics, which are part of a larger group of chemicals known as endocrine-disruptors, since 1990. With Adam Ridden, he is now looking at the chemical dibutyl phthalate, which is used as a plasticiser and in pesticides. While dibutyl phthalate does not have a structure similar to estrogen, it appears to cause developmental defects in children of men exposed to large quantities of the chemical.

Ruth Beran finds out how their research into rat cell lines treated with dibutyl phthalate show increased cortisol production, which would lead to reduced testicular cell development, and also explain why testosterone levels may be reduced in the developing foetus if exposed to the chemical.

Bee-friendly Insecticides

University of Otago geneticist peter dearden and bee

University of Otago geneticist Peter Dearden with one of his study subjects. (image: University of Otago)

Peter Dearden, a geneticist at the University of Otago, describes honey bees as the most important insects on Earth because of the role they play as pollinators. But bees are in trouble worldwide. In New Zealand, the main threat is the Varroa mite which has decimated feral bee colonies throughout the country, but bees are also unintentional targets of the chemicals we use to control insect pests that can damage crops.  

The importance of bees is reflected in the fact that they are the second insect, after the fruit fly Drosophila, whose complete genome has been sequenced. Having studied the larval development of bees and other fundamental aspects of bee physiology and genetics, Peter is now using the knowledge gleaned from the bee genome to develop insecticides that remain effective against pest insects but spare bees.

Next Week

Okarito rowi egg rescue, the development of memory in children, and saving kakabeak in the wild.