Original air date - A Question of Balance :: 7:30pm 26th Jun 2018

Goldmine! Dr Arthur White, explains his work for an Australian mining company that had to deal with a threatened species, the pink-tailed worm lizard. This skinny burrowing lizard has no legs. It’s about 10-15cm and looks like an animated shoelace. It only eats the pupae of a couple of species of ants, crawling down the ant tunnels to eat them. The lizard is listed as a threatened species with a very small population located on the Murrumbidgee River close to the ACT border. In 2001 one of the lizards was found on a site being pegged out for a rare earth mine at Toongi just south of Dubbo. The mining company, Arkane Resources was after the metals niobium, erbium, yttrium and zirconium. These are formed when deep earth lavas come to the surface. The ones at Toongi formed during the Jurassic period and, when the hardened layer eroded away, trachytes were formed. Six were drilled, and one showed economic amounts of the rare earth metals. Niobium, for instance, fetches $180 thousand for each gram! Arkane resources took 10years to formulate a development plan and to get financing, even knocking back Chinese offers (the Chinese control world prices). In 2012 the company engaged Dr White to find out exactly what was going on with the pink-tailed worm lizard so the planners could work out how to develop the site while avoiding critical habitat areas. For three years Dr White flipped over rocks to find the lizards and gathered data on the vegetation, soil type and rock types found. This created a whole series of habitat descriptors across a large region. The variables of vegetation, soil and rock types were then looked at. When the trachytes weathered they did so by onion peeling, the layers ending up as shards on the soils that the lizards used in spring and autumn when they came close to the surface. Since one of the trachytes was going to be mined Dr White then looked at ways of offsetting that habitat loss. Old roof tiles were set up in ten clusters. The tiles were either laid out in single file or in blocks of four the tiles influenced the soil temperature and the soil humidity, particularly under the blocks of tiles. A lot of animals used the tiles (geckos, centipedes, millipedes, grasshoppers) and within six months the pink-tailed worm lizards were also living there. This had the potential to create even more habitat than was going to be lost. The company has worked hard to avoid the other trachytes and is currently doing large-scale habitat recreation. It is a great example of what can be done when a mining company works with scientists. For the company and the lizard the project has turned out to be a goldmine!

Birds’ higher body temperature and super efficient respiratory systems enhances muscle function - but the high blood pressure has a cost: Birds run at a higher metabolic rate than mammals. Their core body temperature is around 40°C, a temperature akin to fever in humans. This means that birds are running at the edge of limitations but it has advantages. For every 10°C increase in temperature, synapse responses improve by a factor of 1.8, muscle contractions become three times more efficient along with greater muscle strength. This allows birds to maintain activities for a very long time, a physical attribute useful in migratory birds. The lungs of birds have adapted to this high metabolic rate, which requires much oxygen and, unlike mammalian lungs, birds get complete oxygen overturn in every breath. The tissue between the blood and air capillaries is much thinner, so the rate of oxygen exchange is much faster. Such oxygen efficiency allows birds to fly at high altitudes. The evolution of birds’ lungs happened somewhere between 175 and 205 million years ago, when oxygen content was about half of what it is today, which is the equivalent to living at 14,000 feet above sea level. Birds also exist with higher blood pressure, making them very prone to heart attacks and strokes. This is especially the case for wild birds that are trapped. This is why it is best to place injured birds in a quiet, dark box, guarding against increased stress. Birds’ hearts are 50 to 100 times larger than mammalian hearts for an equivalent sized body. The blood not only goes to the brain but to the feet to cool their high running bodies. This is done through a special series of shunts that not only radiate more heat but also lose more heat, a process that can be reversed in cold climates.